From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 9 Jul 2019 22:25:46 +0000 (-0700)
Subject: Merge branch 'ds/fetch-disable-force-notice'
X-Git-Tag: v2.23.0-rc0~54
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/cde9a64ea35ceeaa5e8dd2da2662445510fe651c?hp=3883c55138dcfbe2d9a24e3f93a2a4b1d376dde6

Merge branch 'ds/fetch-disable-force-notice'

"git fetch" and "git pull" reports when a fetch results in
non-fast-forward updates to let the user notice unusual situation.
The commands learned "--no-shown-forced-updates" option to disable
this safety feature.

* ds/fetch-disable-force-notice:
pull: add --[no-]show-forced-updates passthrough
fetch: warn about forced updates in branch listing
fetch: add --[no-]show-forced-updates argument
---

diff --git a/.clang-format b/.clang-format
index 41d4cd23fd..c592dda681 100644
--- a/.clang-format
+++ b/.clang-format
@@ -148,8 +148,21 @@ SpacesInSquareBrackets: false
 Cpp11BracedListStyle: false
 
 # A list of macros that should be interpreted as foreach loops instead of as
-# function calls.
-ForEachMacros: ['for_each_string_list_item', 'for_each_wanted_builtin', 'for_each_builtin', 'for_each_ut']
+# function calls. Taken from:
+#   git grep -h '^#define [^[:space:]]*for_each[^[:space:]]*(' \
+#   | sed "s,^#define \([^[:space:]]*for_each[^[:space:]]*\)(.*$,  - '\1'," \
+#   | sort | uniq
+ForEachMacros:
+  - 'for_each_abbrev'
+  - 'for_each_builtin'
+  - 'for_each_string_list_item'
+  - 'for_each_ut'
+  - 'for_each_wanted_builtin'
+  - 'list_for_each'
+  - 'list_for_each_dir'
+  - 'list_for_each_prev'
+  - 'list_for_each_prev_safe'
+  - 'list_for_each_safe'
 
 # The maximum number of consecutive empty lines to keep.
 MaxEmptyLinesToKeep: 1
diff --git a/.gitattributes b/.gitattributes
index 9fa72ad450..b08a1416d8 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -5,6 +5,7 @@
 *.pl eof=lf diff=perl
 *.pm eol=lf diff=perl
 *.py eol=lf diff=python
+*.bat eol=crlf
 /Documentation/**/*.txt eol=lf
 /command-list.txt eol=lf
 /GIT-VERSION-GEN eol=lf
diff --git a/.gitignore b/.gitignore
index 4470d7cfc0..e096e0a51c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -139,6 +139,7 @@
 /git-request-pull
 /git-rerere
 /git-reset
+/git-restore
 /git-rev-list
 /git-rev-parse
 /git-revert
@@ -163,6 +164,7 @@
 /git-submodule
 /git-submodule--helper
 /git-svn
+/git-switch
 /git-symbolic-ref
 /git-tag
 /git-unpack-file
@@ -223,6 +225,11 @@
 *.user
 *.idb
 *.pdb
+*.ilk
+*.iobj
+*.ipdb
+*.dll
+.vs/
 /Debug/
 /Release/
 *.dSYM
diff --git a/Documentation/MyFirstContribution.txt b/Documentation/MyFirstContribution.txt
index 895b7cfd4f..f8670379c0 100644
--- a/Documentation/MyFirstContribution.txt
+++ b/Documentation/MyFirstContribution.txt
@@ -428,7 +428,7 @@ git-psuh - Delight users' typo with a shy horse
 SYNOPSIS
 --------
 [verse]
-'git-psuh'
+'git-psuh [<arg>...]'
 
 DESCRIPTION
 -----------
@@ -491,14 +491,16 @@ Take a look at `Documentation/technical/api-parse-options.txt`. This is a handy
 tool for pulling out options you need to be able to handle, and it takes a
 usage string.
 
-In order to use it, we'll need to prepare a NULL-terminated usage string and a
-`builtin_psuh_options` array. Add a line to `#include "parse-options.h"`.
+In order to use it, we'll need to prepare a NULL-terminated array of usage
+strings and a `builtin_psuh_options` array.
 
-At global scope, add your usage:
+Add a line to `#include "parse-options.h"`.
+
+At global scope, add your array of usage strings:
 
 ----
 static const char * const psuh_usage[] = {
-	N_("git psuh"),
+	N_("git psuh [<arg>...]"),
 	NULL,
 };
 ----
diff --git a/Documentation/RelNotes/2.23.0.txt b/Documentation/RelNotes/2.23.0.txt
index 53e8234e52..a6cd592734 100644
--- a/Documentation/RelNotes/2.23.0.txt
+++ b/Documentation/RelNotes/2.23.0.txt
@@ -43,6 +43,9 @@ UI, Workflows & Features
  * "git help git" was hard to discover (well, at least for some
    people).
 
+ * The pattern "git diff/grep" use to extract funcname and words
+   boundary for Rust has been added.
+
 
 Performance, Internal Implementation, Development Support etc.
 
@@ -148,7 +151,33 @@ Fixes since v2.22
    to honor the "--origin <name>" option.
    (merge 1c4a9f9114 xl/record-partial-clone-origin later to maint).
 
+ * "git fetch" into a lazy clone forgot to fetch base objects that are
+   necessary to complete delta in a thin packfile, which has been
+   corrected.
+   (merge 810e19322d jt/partial-clone-missing-ref-delta-base later to maint).
+
+ * The filter_data used in the list-objects-filter (which manages a
+   lazily sparse clone repository) did not use the dynamic array API
+   correctly---'nr' is supposed to point at one past the last element
+   of the array in use.  This has been corrected.
+   (merge 7140600e2e md/list-objects-filter-memfix later to maint).
+
+ * The description about slashes in gitignore patterns (used to
+   indicate things like "anchored to this level only" and "only
+   matches directories") has been revamped.
+   (merge 1a58bad014 an/ignore-doc-update later to maint).
+
+ * The URL decoding code has been updated to avoid going past the end
+   of the string while parsing %-<hex>-<hex> sequence.
+   (merge d37dc239a4 md/url-parse-harden later to maint).
+
+ * The list of for-each like macros used by clang-format has been
+   updated.
+   (merge fc7e03aace mo/clang-format-for-each-update later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge f547101b26 es/git-debugger-doc later to maint).
    (merge 7877ac3d7b js/bisect-helper-check-get-oid-return-value later to maint).
    (merge 0108f47eb3 sw/git-p4-unshelve-branched-files later to maint).
+   (merge 9df8f734fd cm/send-email-document-req-modules later to maint).
+   (merge afc3bf6eb1 ab/hash-object-doc later to maint).
diff --git a/Documentation/config.txt b/Documentation/config.txt
index 7e2a6f61f5..e3f5bc3396 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -144,6 +144,20 @@ refer to linkgit:gitignore[5] for details. For convenience:
 	This is the same as `gitdir` except that matching is done
 	case-insensitively (e.g. on case-insensitive file sytems)
 
+`onbranch`::
+	The data that follows the keyword `onbranch:` is taken to be a
+	pattern with standard globbing wildcards and two additional
+	ones, `**/` and `/**`, that can match multiple path components.
+	If we are in a worktree where the name of the branch that is
+	currently checked out matches the pattern, the include condition
+	is met.
++
+If the pattern ends with `/`, `**` will be automatically added. For
+example, the pattern `foo/` becomes `foo/**`. In other words, it matches
+all branches that begin with `foo/`. This is useful if your branches are
+organized hierarchically and you would like to apply a configuration to
+all the branches in that hierarchy.
+
 A few more notes on matching via `gitdir` and `gitdir/i`:
 
  * Symlinks in `$GIT_DIR` are not resolved before matching.
@@ -206,6 +220,11 @@ Example
 	[includeIf "gitdir:/path/to/group/"]
 		path = foo.inc
 
+	; include only if we are in a worktree where foo-branch is
+	; currently checked out
+	[includeIf "onbranch:foo-branch"]
+		path = foo.inc
+
 Values
 ~~~~~~
 
diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index 1f1e847fb4..ee85c536ce 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -41,12 +41,19 @@ advice.*::
 		we can still suggest that the user push to either
 		refs/heads/* or refs/tags/* based on the type of the
 		source object.
+	statusAheadBehind::
+		Shown when linkgit:git-status[1] computes the ahead/behind
+		counts for a local ref compared to its remote tracking ref,
+		and that calculation takes longer than expected. Will not
+		appear if `status.aheadBehind` is false or the option
+		`--no-ahead-behind` is given.
 	statusHints::
 		Show directions on how to proceed from the current
 		state in the output of linkgit:git-status[1], in
 		the template shown when writing commit messages in
 		linkgit:git-commit[1], and in the help message shown
-		by linkgit:git-checkout[1] when switching branch.
+		by linkgit:git-switch[1] or
+		linkgit:git-checkout[1] when switching branch.
 	statusUoption::
 		Advise to consider using the `-u` option to linkgit:git-status[1]
 		when the command takes more than 2 seconds to enumerate untracked
@@ -66,12 +73,14 @@ advice.*::
 		your information is guessed from the system username and
 		domain name.
 	detachedHead::
-		Advice shown when you used linkgit:git-checkout[1] to
-		move to the detach HEAD state, to instruct how to create
-		a local branch after the fact.
+		Advice shown when you used
+		linkgit:git-switch[1] or linkgit:git-checkout[1]
+		to move to the detach HEAD state, to instruct how to
+		create a local branch after the fact.
 	checkoutAmbiguousRemoteBranchName::
 		Advice shown when the argument to
-		linkgit:git-checkout[1] ambiguously resolves to a
+		linkgit:git-checkout[1] and linkgit:git-switch[1]
+		ambiguously resolves to a
 		remote tracking branch on more than one remote in
 		situations where an unambiguous argument would have
 		otherwise caused a remote-tracking branch to be
diff --git a/Documentation/config/alias.txt b/Documentation/config/alias.txt
index 0b14178314..f1ca739d57 100644
--- a/Documentation/config/alias.txt
+++ b/Documentation/config/alias.txt
@@ -1,18 +1,28 @@
 alias.*::
 	Command aliases for the linkgit:git[1] command wrapper - e.g.
-	after defining "alias.last = cat-file commit HEAD", the invocation
-	"git last" is equivalent to "git cat-file commit HEAD". To avoid
+	after defining `alias.last = cat-file commit HEAD`, the invocation
+	`git last` is equivalent to `git cat-file commit HEAD`. To avoid
 	confusion and troubles with script usage, aliases that
 	hide existing Git commands are ignored. Arguments are split by
 	spaces, the usual shell quoting and escaping is supported.
 	A quote pair or a backslash can be used to quote them.
 +
+Note that the first word of an alias does not necessarily have to be a
+command. It can be a command-line option that will be passed into the
+invocation of `git`. In particular, this is useful when used with `-c`
+to pass in one-time configurations or `-p` to force pagination. For example,
+`loud-rebase = -c commit.verbose=true rebase` can be defined such that
+running `git loud-rebase` would be equivalent to
+`git -c commit.verbose=true rebase`. Also, `ps = -p status` would be a
+helpful alias since `git ps` would paginate the output of `git status`
+where the original command does not.
++
 If the alias expansion is prefixed with an exclamation point,
 it will be treated as a shell command.  For example, defining
-"alias.new = !gitk --all --not ORIG_HEAD", the invocation
-"git new" is equivalent to running the shell command
-"gitk --all --not ORIG_HEAD".  Note that shell commands will be
+`alias.new = !gitk --all --not ORIG_HEAD`, the invocation
+`git new` is equivalent to running the shell command
+`gitk --all --not ORIG_HEAD`.  Note that shell commands will be
 executed from the top-level directory of a repository, which may
 not necessarily be the current directory.
-`GIT_PREFIX` is set as returned by running 'git rev-parse --show-prefix'
+`GIT_PREFIX` is set as returned by running `git rev-parse --show-prefix`
 from the original current directory. See linkgit:git-rev-parse[1].
diff --git a/Documentation/config/branch.txt b/Documentation/config/branch.txt
index 8f4b3faadd..a592d522a7 100644
--- a/Documentation/config/branch.txt
+++ b/Documentation/config/branch.txt
@@ -1,5 +1,5 @@
 branch.autoSetupMerge::
-	Tells 'git branch' and 'git checkout' to set up new branches
+	Tells 'git branch', 'git switch' and 'git checkout' to set up new branches
 	so that linkgit:git-pull[1] will appropriately merge from the
 	starting point branch. Note that even if this option is not set,
 	this behavior can be chosen per-branch using the `--track`
@@ -11,7 +11,7 @@ branch.autoSetupMerge::
 	branch. This option defaults to true.
 
 branch.autoSetupRebase::
-	When a new branch is created with 'git branch' or 'git checkout'
+	When a new branch is created with 'git branch', 'git switch' or 'git checkout'
 	that tracks another branch, this variable tells Git to set
 	up pull to rebase instead of merge (see "branch.<name>.rebase").
 	When `never`, rebase is never automatically set to true.
diff --git a/Documentation/config/checkout.txt b/Documentation/config/checkout.txt
index c4118fa196..6b646813ab 100644
--- a/Documentation/config/checkout.txt
+++ b/Documentation/config/checkout.txt
@@ -1,5 +1,6 @@
 checkout.defaultRemote::
-	When you run 'git checkout <something>' and only have one
+	When you run 'git checkout <something>'
+	or 'git switch <something>' and only have one
 	remote, it may implicitly fall back on checking out and
 	tracking e.g. 'origin/<something>'. This stops working as soon
 	as you have more than one remote with a '<something>'
@@ -8,16 +9,10 @@ checkout.defaultRemote::
 	disambiguation. The typical use-case is to set this to
 	`origin`.
 +
-Currently this is used by linkgit:git-checkout[1] when 'git checkout
-<something>' will checkout the '<something>' branch on another remote,
+Currently this is used by linkgit:git-switch[1] and
+linkgit:git-checkout[1] when 'git checkout <something>'
+or 'git switch <something>'
+will checkout the '<something>' branch on another remote,
 and by linkgit:git-worktree[1] when 'git worktree add' refers to a
 remote branch. This setting might be used for other checkout-like
 commands or functionality in the future.
-
-checkout.optimizeNewBranch::
-	Optimizes the performance of "git checkout -b <new_branch>" when
-	using sparse-checkout.  When set to true, git will not update the
-	repo based on the current sparse-checkout settings.  This means it
-	will not update the skip-worktree bit in the index nor add/remove
-	files in the working directory to reflect the current sparse checkout
-	settings nor will it show the local changes.
diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt
index 2c4c9ba27a..5afb5a2cbc 100644
--- a/Documentation/config/diff.txt
+++ b/Documentation/config/diff.txt
@@ -78,7 +78,8 @@ diff.external::
 diff.ignoreSubmodules::
 	Sets the default value of --ignore-submodules. Note that this
 	affects only 'git diff' Porcelain, and not lower level 'diff'
-	commands such as 'git diff-files'. 'git checkout' also honors
+	commands such as 'git diff-files'. 'git checkout'
+	and 'git switch' also honor
 	this setting when reporting uncommitted changes. Setting it to
 	'all' disables the submodule summary normally shown by 'git commit'
 	and 'git status' when `status.submoduleSummary` is set unless it is
diff --git a/Documentation/config/interactive.txt b/Documentation/config/interactive.txt
index ad846dd7c9..a2d3c7ec44 100644
--- a/Documentation/config/interactive.txt
+++ b/Documentation/config/interactive.txt
@@ -2,7 +2,8 @@ interactive.singleKey::
 	In interactive commands, allow the user to provide one-letter
 	input with a single key (i.e., without hitting enter).
 	Currently this is used by the `--patch` mode of
-	linkgit:git-add[1], linkgit:git-checkout[1], linkgit:git-commit[1],
+	linkgit:git-add[1], linkgit:git-checkout[1],
+	linkgit:git-restore[1], linkgit:git-commit[1],
 	linkgit:git-reset[1], and linkgit:git-stash[1]. Note that this
 	setting is silently ignored if portable keystroke input
 	is not available; requires the Perl module Term::ReadKey.
diff --git a/Documentation/config/status.txt b/Documentation/config/status.txt
index ed72fa7dae..0fc704ab80 100644
--- a/Documentation/config/status.txt
+++ b/Documentation/config/status.txt
@@ -12,6 +12,11 @@ status.branch::
 	Set to true to enable --branch by default in linkgit:git-status[1].
 	The option --no-branch takes precedence over this variable.
 
+status.aheadBehind::
+	Set to true to enable `--ahead-behind` and false to enable
+	`--no-ahead-behind` by default in linkgit:git-status[1] for
+	non-porcelain status formats.  Defaults to true.
+
 status.displayCommentPrefix::
 	If set to true, linkgit:git-status[1] will insert a comment
 	prefix before each output line (starting with
diff --git a/Documentation/config/tag.txt b/Documentation/config/tag.txt
index 663663bdec..ef5adb3f42 100644
--- a/Documentation/config/tag.txt
+++ b/Documentation/config/tag.txt
@@ -8,6 +8,14 @@ tag.sort::
 	linkgit:git-tag[1]. Without the "--sort=<value>" option provided, the
 	value of this variable will be used as the default.
 
+tag.gpgSign::
+	A boolean to specify whether all tags should be GPG signed.
+	Use of this option when running in an automated script can
+	result in a large number of tags being signed. It is therefore
+	convenient to use an agent to avoid typing your gpg passphrase
+	several times. Note that this option doesn't affects tag signing
+	behavior enabled by "-u <keyid>" or "--local-user=<keyid>" options.
+
 tar.umask::
 	This variable can be used to restrict the permission bits of
 	tar archive entries.  The default is 0002, which turns off the
diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt
index 5801d23ae4..3c9b4f9e09 100644
--- a/Documentation/fetch-options.txt
+++ b/Documentation/fetch-options.txt
@@ -88,6 +88,10 @@ ifndef::git-pull[]
 	Allow several <repository> and <group> arguments to be
 	specified. No <refspec>s may be specified.
 
+--[no-]auto-gc::
+	Run `git gc --auto` at the end to perform garbage collection
+	if needed. This is enabled by default.
+
 -p::
 --prune::
 	Before fetching, remove any remote-tracking references that no
diff --git a/Documentation/git-branch.txt b/Documentation/git-branch.txt
index 6ebd512b4f..135206ff4a 100644
--- a/Documentation/git-branch.txt
+++ b/Documentation/git-branch.txt
@@ -8,12 +8,14 @@ git-branch - List, create, or delete branches
 SYNOPSIS
 --------
 [verse]
-'git branch' [--color[=<when>] | --no-color] [-r | -a]
-	[--list] [--show-current] [-v [--abbrev=<length> | --no-abbrev]]
+'git branch' [--color[=<when>] | --no-color] [--show-current]
+	[-v [--abbrev=<length> | --no-abbrev]]
 	[--column[=<options>] | --no-column] [--sort=<key>]
 	[(--merged | --no-merged) [<commit>]]
 	[--contains [<commit]] [--no-contains [<commit>]]
-	[--points-at <object>] [--format=<format>] [<pattern>...]
+	[--points-at <object>] [--format=<format>]
+	[(-r | --remotes) | (-a | --all)]
+	[--list] [<pattern>...]
 'git branch' [--track | --no-track] [-f] <branchname> [<start-point>]
 'git branch' (--set-upstream-to=<upstream> | -u <upstream>) [<branchname>]
 'git branch' --unset-upstream [<branchname>]
@@ -26,13 +28,19 @@ DESCRIPTION
 -----------
 
 If `--list` is given, or if there are no non-option arguments, existing
-branches are listed; the current branch will be highlighted with an
-asterisk.  Option `-r` causes the remote-tracking branches to be listed,
-and option `-a` shows both local and remote branches. If a `<pattern>`
+branches are listed; the current branch will be highlighted in green and
+marked with an asterisk.  Any branches checked out in linked worktrees will
+be highlighted in cyan and marked with a plus sign. Option `-r` causes the
+remote-tracking branches to be listed,
+and option `-a` shows both local and remote branches.
+
+If a `<pattern>`
 is given, it is used as a shell wildcard to restrict the output to
 matching branches. If multiple patterns are given, a branch is shown if
-it matches any of the patterns.  Note that when providing a
-`<pattern>`, you must use `--list`; otherwise the command is interpreted
+it matches any of the patterns.
+
+Note that when providing a
+`<pattern>`, you must use `--list`; otherwise the command may be interpreted
 as branch creation.
 
 With `--contains`, shows only the branches that contain the named commit
@@ -52,7 +60,7 @@ can leave out at most one of `A` and `B`, in which case it defaults to
 `HEAD`.
 
 Note that this will create the new branch, but it will not switch the
-working tree to it; use "git checkout <newbranch>" to switch to the
+working tree to it; use "git switch <newbranch>" to switch to the
 new branch.
 
 When a local branch is started off a remote-tracking branch, Git sets up the
@@ -153,10 +161,12 @@ This option is only applicable in non-verbose mode.
 -r::
 --remotes::
 	List or delete (if used with -d) the remote-tracking branches.
+	Combine with `--list` to match the optional pattern(s).
 
 -a::
 --all::
 	List both remote-tracking branches and local branches.
+	Combine with `--list` to match optional pattern(s).
 
 -l::
 --list::
@@ -174,8 +184,10 @@ This option is only applicable in non-verbose mode.
 	When in list mode,
 	show sha1 and commit subject line for each head, along with
 	relationship to upstream branch (if any). If given twice, print
-	the name of the upstream branch, as well (see also `git remote
-	show <remote>`).
+	the path of the linked worktree (if any) and the name of the upstream
+	branch, as well (see also `git remote show <remote>`).  Note that the
+	current worktree's HEAD will not have its path printed (it will always
+	be your current directory).
 
 -q::
 --quiet::
@@ -202,7 +214,7 @@ This option is only applicable in non-verbose mode.
 +
 This behavior is the default when the start point is a remote-tracking branch.
 Set the branch.autoSetupMerge configuration variable to `false` if you
-want `git checkout` and `git branch` to always behave as if `--no-track`
+want `git switch`, `git checkout` and `git branch` to always behave as if `--no-track`
 were given. Set it to `always` if you want this behavior when the
 start-point is either a local or remote-tracking branch.
 
@@ -301,7 +313,7 @@ Start development from a known tag::
 $ git clone git://git.kernel.org/pub/scm/.../linux-2.6 my2.6
 $ cd my2.6
 $ git branch my2.6.14 v2.6.14   <1>
-$ git checkout my2.6.14
+$ git switch my2.6.14
 ------------
 +
 <1> This step and the next one could be combined into a single step with
@@ -322,13 +334,25 @@ $ git branch -D test                                    <2>
 <2> Delete the "test" branch even if the "master" branch (or whichever branch
     is currently checked out) does not have all commits from the test branch.
 
+Listing branches from a specific remote::
++
+------------
+$ git branch -r -l '<remote>/<pattern>'                 <1>
+$ git for-each-ref 'refs/remotes/<remote>/<pattern>'    <2>
+------------
++
+<1> Using `-a` would conflate <remote> with any local branches you happen to
+    have been prefixed with the same <remote> pattern.
+<2> `for-each-ref` can take a wide range of options. See linkgit:git-for-each-ref[1]
+
+Patterns will normally need quoting.
 
 NOTES
 -----
 
-If you are creating a branch that you want to checkout immediately, it is
-easier to use the git checkout command with its `-b` option to create
-a branch and check it out with a single command.
+If you are creating a branch that you want to switch to immediately,
+it is easier to use the "git switch" command with its `-c` option to
+do the same thing with a single command.
 
 The options `--contains`, `--no-contains`, `--merged` and `--no-merged`
 serve four related but different purposes:
diff --git a/Documentation/git-check-ref-format.txt b/Documentation/git-check-ref-format.txt
index d9de992585..ee6a4144fb 100644
--- a/Documentation/git-check-ref-format.txt
+++ b/Documentation/git-check-ref-format.txt
@@ -88,7 +88,8 @@ but it is explicitly forbidden at the beginning of a branch name).
 When run with `--branch` option in a repository, the input is first
 expanded for the ``previous checkout syntax''
 `@{-n}`.  For example, `@{-1}` is a way to refer the last thing that
-was checked out using "git checkout" operation. This option should be
+was checked out using "git switch" or "git checkout" operation.
+This option should be
 used by porcelains to accept this syntax anywhere a branch name is
 expected, so they can act as if you typed the branch name. As an
 exception note that, the ``previous checkout operation'' might result
diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 964f912d29..cf3cac0a2b 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -23,31 +23,22 @@ or the specified tree.  If no paths are given, 'git checkout' will
 also update `HEAD` to set the specified branch as the current
 branch.
 
-'git checkout' <branch>::
-	To prepare for working on <branch>, switch to it by updating
+'git checkout' [<branch>]::
+	To prepare for working on `<branch>`, switch to it by updating
 	the index and the files in the working tree, and by pointing
-	HEAD at the branch. Local modifications to the files in the
+	`HEAD` at the branch. Local modifications to the files in the
 	working tree are kept, so that they can be committed to the
-	<branch>.
+	`<branch>`.
 +
-If <branch> is not found but there does exist a tracking branch in
-exactly one remote (call it <remote>) with a matching name, treat as
-equivalent to
+If `<branch>` is not found but there does exist a tracking branch in
+exactly one remote (call it `<remote>`) with a matching name and
+`--no-guess` is not specified, treat as equivalent to
 +
 ------------
 $ git checkout -b <branch> --track <remote>/<branch>
 ------------
 +
-If the branch exists in multiple remotes and one of them is named by
-the `checkout.defaultRemote` configuration variable, we'll use that
-one for the purposes of disambiguation, even if the `<branch>` isn't
-unique across all remotes. Set it to
-e.g. `checkout.defaultRemote=origin` to always checkout remote
-branches from there if `<branch>` is ambiguous but exists on the
-'origin' remote. See also `checkout.defaultRemote` in
-linkgit:git-config[1].
-+
-You could omit <branch>, in which case the command degenerates to
+You could omit `<branch>`, in which case the command degenerates to
 "check out the current branch", which is a glorified no-op with
 rather expensive side-effects to show only the tracking information,
 if exists, for the current branch.
@@ -61,7 +52,7 @@ if exists, for the current branch.
 	`--track` without `-b` implies branch creation; see the
 	description of `--track` below.
 +
-If `-B` is given, <new_branch> is created if it doesn't exist; otherwise, it
+If `-B` is given, `<new_branch>` is created if it doesn't exist; otherwise, it
 is reset. This is the transactional equivalent of
 +
 ------------
@@ -75,25 +66,25 @@ successful.
 'git checkout' --detach [<branch>]::
 'git checkout' [--detach] <commit>::
 
-	Prepare to work on top of <commit>, by detaching HEAD at it
+	Prepare to work on top of `<commit>`, by detaching `HEAD` at it
 	(see "DETACHED HEAD" section), and updating the index and the
 	files in the working tree.  Local modifications to the files
 	in the working tree are kept, so that the resulting working
 	tree will be the state recorded in the commit plus the local
 	modifications.
 +
-When the <commit> argument is a branch name, the `--detach` option can
-be used to detach HEAD at the tip of the branch (`git checkout
-<branch>` would check out that branch without detaching HEAD).
+When the `<commit>` argument is a branch name, the `--detach` option can
+be used to detach `HEAD` at the tip of the branch (`git checkout
+<branch>` would check out that branch without detaching `HEAD`).
 +
-Omitting <branch> detaches HEAD at the tip of the current branch.
+Omitting `<branch>` detaches `HEAD` at the tip of the current branch.
 
 'git checkout' [<tree-ish>] [--] <pathspec>...::
 
 	Overwrite paths in the working tree by replacing with the
-	contents in the index or in the <tree-ish> (most often a
-	commit).  When a <tree-ish> is given, the paths that
-	match the <pathspec> are updated both in the index and in
+	contents in the index or in the `<tree-ish>` (most often a
+	commit).  When a `<tree-ish>` is given, the paths that
+	match the `<pathspec>` are updated both in the index and in
 	the working tree.
 +
 The index may contain unmerged entries because of a previous failed merge.
@@ -118,7 +109,8 @@ OPTIONS
 --quiet::
 	Quiet, suppress feedback messages.
 
---[no-]progress::
+--progress::
+--no-progress::
 	Progress status is reported on the standard error stream
 	by default when it is attached to a terminal, unless `--quiet`
 	is specified. This flag enables progress reporting even if not
@@ -127,7 +119,7 @@ OPTIONS
 -f::
 --force::
 	When switching branches, proceed even if the index or the
-	working tree differs from HEAD.  This is used to throw away
+	working tree differs from `HEAD`.  This is used to throw away
 	local changes.
 +
 When checking out paths from the index, do not fail upon unmerged
@@ -154,12 +146,12 @@ on your side branch as `theirs` (i.e. "one contributor's work on top
 of it").
 
 -b <new_branch>::
-	Create a new branch named <new_branch> and start it at
-	<start_point>; see linkgit:git-branch[1] for details.
+	Create a new branch named `<new_branch>` and start it at
+	`<start_point>`; see linkgit:git-branch[1] for details.
 
 -B <new_branch>::
-	Creates the branch <new_branch> and start it at <start_point>;
-	if it already exists, then reset it to <start_point>. This is
+	Creates the branch `<new_branch>` and start it at `<start_point>`;
+	if it already exists, then reset it to `<start_point>`. This is
 	equivalent to running "git branch" with "-f"; see
 	linkgit:git-branch[1] for details.
 
@@ -172,15 +164,36 @@ If no `-b` option is given, the name of the new branch will be
 derived from the remote-tracking branch, by looking at the local part of
 the refspec configured for the corresponding remote, and then stripping
 the initial part up to the "*".
-This would tell us to use "hack" as the local branch when branching
-off of "origin/hack" (or "remotes/origin/hack", or even
-"refs/remotes/origin/hack").  If the given name has no slash, or the above
+This would tell us to use `hack` as the local branch when branching
+off of `origin/hack` (or `remotes/origin/hack`, or even
+`refs/remotes/origin/hack`).  If the given name has no slash, or the above
 guessing results in an empty name, the guessing is aborted.  You can
 explicitly give a name with `-b` in such a case.
 
 --no-track::
 	Do not set up "upstream" configuration, even if the
-	branch.autoSetupMerge configuration variable is true.
+	`branch.autoSetupMerge` configuration variable is true.
+
+--guess::
+--no-guess::
+	If `<branch>` is not found but there does exist a tracking
+	branch in exactly one remote (call it `<remote>`) with a
+	matching name, treat as equivalent to
++
+------------
+$ git checkout -b <branch> --track <remote>/<branch>
+------------
++
+If the branch exists in multiple remotes and one of them is named by
+the `checkout.defaultRemote` configuration variable, we'll use that
+one for the purposes of disambiguation, even if the `<branch>` isn't
+unique across all remotes. Set it to
+e.g. `checkout.defaultRemote=origin` to always checkout remote
+branches from there if `<branch>` is ambiguous but exists on the
+'origin' remote. See also `checkout.defaultRemote` in
+linkgit:git-config[1].
++
+Use `--no-guess` to disable this.
 
 -l::
 	Create the new branch's reflog; see linkgit:git-branch[1] for
@@ -189,21 +202,21 @@ explicitly give a name with `-b` in such a case.
 --detach::
 	Rather than checking out a branch to work on it, check out a
 	commit for inspection and discardable experiments.
-	This is the default behavior of "git checkout <commit>" when
-	<commit> is not a branch name.  See the "DETACHED HEAD" section
+	This is the default behavior of `git checkout <commit>` when
+	`<commit>` is not a branch name.  See the "DETACHED HEAD" section
 	below for details.
 
 --orphan <new_branch>::
-	Create a new 'orphan' branch, named <new_branch>, started from
-	<start_point> and switch to it.  The first commit made on this
+	Create a new 'orphan' branch, named `<new_branch>`, started from
+	`<start_point>` and switch to it.  The first commit made on this
 	new branch will have no parents and it will be the root of a new
 	history totally disconnected from all the other branches and
 	commits.
 +
 The index and the working tree are adjusted as if you had previously run
-"git checkout <start_point>".  This allows you to start a new history
-that records a set of paths similar to <start_point> by easily running
-"git commit -a" to make the root commit.
+`git checkout <start_point>`.  This allows you to start a new history
+that records a set of paths similar to `<start_point>` by easily running
+`git commit -a` to make the root commit.
 +
 This can be useful when you want to publish the tree from a commit
 without exposing its full history. You might want to do this to publish
@@ -212,17 +225,17 @@ whose full history contains proprietary or otherwise encumbered bits of
 code.
 +
 If you want to start a disconnected history that records a set of paths
-that is totally different from the one of <start_point>, then you should
+that is totally different from the one of `<start_point>`, then you should
 clear the index and the working tree right after creating the orphan
-branch by running "git rm -rf ." from the top level of the working tree.
+branch by running `git rm -rf .` from the top level of the working tree.
 Afterwards you will be ready to prepare your new files, repopulating the
 working tree, by copying them from elsewhere, extracting a tarball, etc.
 
 --ignore-skip-worktree-bits::
 	In sparse checkout mode, `git checkout -- <paths>` would
-	update only entries matched by <paths> and sparse patterns
-	in $GIT_DIR/info/sparse-checkout. This option ignores
-	the sparse patterns and adds back any files in <paths>.
+	update only entries matched by `<paths>` and sparse patterns
+	in `$GIT_DIR/info/sparse-checkout`. This option ignores
+	the sparse patterns and adds back any files in `<paths>`.
 
 -m::
 --merge::
@@ -246,25 +259,25 @@ the conflicted merge in the specified paths.
 When switching branches with `--merge`, staged changes may be lost.
 
 --conflict=<style>::
-	The same as --merge option above, but changes the way the
+	The same as `--merge` option above, but changes the way the
 	conflicting hunks are presented, overriding the
-	merge.conflictStyle configuration variable.  Possible values are
+	`merge.conflictStyle` configuration variable.  Possible values are
 	"merge" (default) and "diff3" (in addition to what is shown by
 	"merge" style, shows the original contents).
 
 -p::
 --patch::
 	Interactively select hunks in the difference between the
-	<tree-ish> (or the index, if unspecified) and the working
+	`<tree-ish>` (or the index, if unspecified) and the working
 	tree.  The chosen hunks are then applied in reverse to the
-	working tree (and if a <tree-ish> was specified, the index).
+	working tree (and if a `<tree-ish>` was specified, the index).
 +
 This means that you can use `git checkout -p` to selectively discard
 edits from your current working tree. See the ``Interactive Mode''
 section of linkgit:git-add[1] to learn how to operate the `--patch` mode.
 +
 Note that this option uses the no overlay mode by default (see also
-`--[no-]overlay`), and currently doesn't support overlay mode.
+`--overlay`), and currently doesn't support overlay mode.
 
 --ignore-other-worktrees::
 	`git checkout` refuses when the wanted ref is already checked
@@ -272,38 +285,42 @@ Note that this option uses the no overlay mode by default (see also
 	out anyway. In other words, the ref can be held by more than one
 	worktree.
 
---[no-]recurse-submodules::
-	Using --recurse-submodules will update the content of all initialized
+--overwrite-ignore::
+--no-overwrite-ignore::
+	Silently overwrite ignored files when switching branches. This
+	is the default behavior. Use `--no-overwrite-ignore` to abort
+	the operation when the new branch contains ignored files.
+
+--recurse-submodules::
+--no-recurse-submodules::
+	Using `--recurse-submodules` will update the content of all initialized
 	submodules according to the commit recorded in the superproject. If
 	local modifications in a submodule would be overwritten the checkout
-	will fail unless `-f` is used. If nothing (or --no-recurse-submodules)
+	will fail unless `-f` is used. If nothing (or `--no-recurse-submodules`)
 	is used, the work trees of submodules will not be updated.
-	Just like linkgit:git-submodule[1], this will detach the
-	submodules HEAD.
-
---no-guess::
-	Do not attempt to create a branch if a remote tracking branch
-	of the same name exists.
+	Just like linkgit:git-submodule[1], this will detach `HEAD` of the
+	submodule.
 
---[no-]overlay::
+--overlay::
+--no-overlay::
 	In the default overlay mode, `git checkout` never
 	removes files from the index or the working tree.  When
 	specifying `--no-overlay`, files that appear in the index and
-	working tree, but not in <tree-ish> are removed, to make them
-	match <tree-ish> exactly.
+	working tree, but not in `<tree-ish>` are removed, to make them
+	match `<tree-ish>` exactly.
 
 <branch>::
 	Branch to checkout; if it refers to a branch (i.e., a name that,
 	when prepended with "refs/heads/", is a valid ref), then that
 	branch is checked out. Otherwise, if it refers to a valid
-	commit, your HEAD becomes "detached" and you are no longer on
+	commit, your `HEAD` becomes "detached" and you are no longer on
 	any branch (see below for details).
 +
-You can use the `"@{-N}"` syntax to refer to the N-th last
+You can use the `@{-N}` syntax to refer to the N-th last
 branch/commit checked out using "git checkout" operation. You may
-also specify `-` which is synonymous to `"@{-1}"`.
+also specify `-` which is synonymous to `@{-1}`.
 +
-As a special case, you may use `"A...B"` as a shortcut for the
+As a special case, you may use `A...B` as a shortcut for the
 merge base of `A` and `B` if there is exactly one merge base. You can
 leave out at most one of `A` and `B`, in which case it defaults to `HEAD`.
 
@@ -312,7 +329,7 @@ leave out at most one of `A` and `B`, in which case it defaults to `HEAD`.
 
 <start_point>::
 	The name of a commit at which to start the new branch; see
-	linkgit:git-branch[1] for details. Defaults to HEAD.
+	linkgit:git-branch[1] for details. Defaults to `HEAD`.
 +
 As a special case, you may use `"A...B"` as a shortcut for the
 merge base of `A` and `B` if there is exactly one merge base. You can
@@ -326,9 +343,9 @@ leave out at most one of `A` and `B`, in which case it defaults to `HEAD`.
 
 DETACHED HEAD
 -------------
-HEAD normally refers to a named branch (e.g. 'master'). Meanwhile, each
+`HEAD` normally refers to a named branch (e.g. `master`). Meanwhile, each
 branch refers to a specific commit. Let's look at a repo with three
-commits, one of them tagged, and with branch 'master' checked out:
+commits, one of them tagged, and with branch `master` checked out:
 
 ------------
            HEAD (refers to branch 'master')
@@ -341,10 +358,10 @@ a---b---c  branch 'master' (refers to commit 'c')
 ------------
 
 When a commit is created in this state, the branch is updated to refer to
-the new commit. Specifically, 'git commit' creates a new commit 'd', whose
-parent is commit 'c', and then updates branch 'master' to refer to new
-commit 'd'. HEAD still refers to branch 'master' and so indirectly now refers
-to commit 'd':
+the new commit. Specifically, 'git commit' creates a new commit `d`, whose
+parent is commit `c`, and then updates branch `master` to refer to new
+commit `d`. `HEAD` still refers to branch `master` and so indirectly now refers
+to commit `d`:
 
 ------------
 $ edit; git add; git commit
@@ -361,7 +378,7 @@ a---b---c---d  branch 'master' (refers to commit 'd')
 It is sometimes useful to be able to checkout a commit that is not at
 the tip of any named branch, or even to create a new commit that is not
 referenced by a named branch. Let's look at what happens when we
-checkout commit 'b' (here we show two ways this may be done):
+checkout commit `b` (here we show two ways this may be done):
 
 ------------
 $ git checkout v2.0  # or
@@ -376,9 +393,9 @@ a---b---c---d  branch 'master' (refers to commit 'd')
   tag 'v2.0' (refers to commit 'b')
 ------------
 
-Notice that regardless of which checkout command we use, HEAD now refers
-directly to commit 'b'. This is known as being in detached HEAD state.
-It means simply that HEAD refers to a specific commit, as opposed to
+Notice that regardless of which checkout command we use, `HEAD` now refers
+directly to commit `b`. This is known as being in detached `HEAD` state.
+It means simply that `HEAD` refers to a specific commit, as opposed to
 referring to a named branch. Let's see what happens when we create a commit:
 
 ------------
@@ -395,7 +412,7 @@ a---b---c---d  branch 'master' (refers to commit 'd')
   tag 'v2.0' (refers to commit 'b')
 ------------
 
-There is now a new commit 'e', but it is referenced only by HEAD. We can
+There is now a new commit `e`, but it is referenced only by `HEAD`. We can
 of course add yet another commit in this state:
 
 ------------
@@ -413,7 +430,7 @@ a---b---c---d  branch 'master' (refers to commit 'd')
 ------------
 
 In fact, we can perform all the normal Git operations. But, let's look
-at what happens when we then checkout master:
+at what happens when we then checkout `master`:
 
 ------------
 $ git checkout master
@@ -428,9 +445,9 @@ a---b---c---d  branch 'master' (refers to commit 'd')
 ------------
 
 It is important to realize that at this point nothing refers to commit
-'f'. Eventually commit 'f' (and by extension commit 'e') will be deleted
+`f`. Eventually commit `f` (and by extension commit `e`) will be deleted
 by the routine Git garbage collection process, unless we create a reference
-before that happens. If we have not yet moved away from commit 'f',
+before that happens. If we have not yet moved away from commit `f`,
 any of these will create a reference to it:
 
 ------------
@@ -439,19 +456,19 @@ $ git branch foo        <2>
 $ git tag foo           <3>
 ------------
 
-<1> creates a new branch 'foo', which refers to commit 'f', and then
-    updates HEAD to refer to branch 'foo'. In other words, we'll no longer
-    be in detached HEAD state after this command.
+<1> creates a new branch `foo`, which refers to commit `f`, and then
+    updates `HEAD` to refer to branch `foo`. In other words, we'll no longer
+    be in detached `HEAD` state after this command.
 
-<2> similarly creates a new branch 'foo', which refers to commit 'f',
-    but leaves HEAD detached.
+<2> similarly creates a new branch `foo`, which refers to commit `f`,
+    but leaves `HEAD` detached.
 
-<3> creates a new tag 'foo', which refers to commit 'f',
-    leaving HEAD detached.
+<3> creates a new tag `foo`, which refers to commit `f`,
+    leaving `HEAD` detached.
 
-If we have moved away from commit 'f', then we must first recover its object
+If we have moved away from commit `f`, then we must first recover its object
 name (typically by using git reflog), and then we can create a reference to
-it. For example, to see the last two commits to which HEAD referred, we
+it. For example, to see the last two commits to which `HEAD` referred, we
 can use either of these commands:
 
 ------------
@@ -462,12 +479,12 @@ $ git log -g -2 HEAD
 ARGUMENT DISAMBIGUATION
 -----------------------
 
-When there is only one argument given and it is not `--` (e.g. "git
-checkout abc"), and when the argument is both a valid `<tree-ish>`
-(e.g. a branch "abc" exists) and a valid `<pathspec>` (e.g. a file
+When there is only one argument given and it is not `--` (e.g. `git
+checkout abc`), and when the argument is both a valid `<tree-ish>`
+(e.g. a branch `abc` exists) and a valid `<pathspec>` (e.g. a file
 or a directory whose name is "abc" exists), Git would usually ask
 you to disambiguate.  Because checking out a branch is so common an
-operation, however, "git checkout abc" takes "abc" as a `<tree-ish>`
+operation, however, `git checkout abc` takes "abc" as a `<tree-ish>`
 in such a situation.  Use `git checkout -- <pathspec>` if you want
 to checkout these paths out of the index.
 
@@ -475,7 +492,7 @@ EXAMPLES
 --------
 
 . The following sequence checks out the `master` branch, reverts
-  the `Makefile` to two revisions back, deletes hello.c by
+  the `Makefile` to two revisions back, deletes `hello.c` by
   mistake, and gets it back from the index.
 +
 ------------
@@ -487,7 +504,7 @@ $ git checkout hello.c            <3>
 +
 <1> switch branch
 <2> take a file out of another commit
-<3> restore hello.c from the index
+<3> restore `hello.c` from the index
 +
 If you want to check out _all_ C source files out of the index,
 you can say
@@ -516,7 +533,7 @@ $ git checkout -- hello.c
 $ git checkout mytopic
 ------------
 +
-However, your "wrong" branch and correct "mytopic" branch may
+However, your "wrong" branch and correct `mytopic` branch may
 differ in files that you have modified locally, in which case
 the above checkout would fail like this:
 +
@@ -557,6 +574,11 @@ $ edit frotz
 $ git add frotz
 ------------
 
+SEE ALSO
+--------
+linkgit:git-switch[1],
+linkgit:git-restore[1]
+
 GIT
 ---
 Part of the linkgit:git[1] suite
diff --git a/Documentation/git-clean.txt b/Documentation/git-clean.txt
index db876f7dde..0028ff12d1 100644
--- a/Documentation/git-clean.txt
+++ b/Documentation/git-clean.txt
@@ -63,7 +63,7 @@ OPTIONS
 	still use the ignore rules given with `-e` options from the command
 	line.  This allows removing all untracked
 	files, including build products.  This can be used (possibly in
-	conjunction with 'git reset') to create a pristine
+	conjunction with 'git restore' or 'git reset') to create a pristine
 	working directory to test a clean build.
 
 -X::
diff --git a/Documentation/git-commit.txt b/Documentation/git-commit.txt
index a85c2c2a4c..7628193284 100644
--- a/Documentation/git-commit.txt
+++ b/Documentation/git-commit.txt
@@ -359,7 +359,7 @@ When recording your own work, the contents of modified files in
 your working tree are temporarily stored to a staging area
 called the "index" with 'git add'.  A file can be
 reverted back, only in the index but not in the working tree,
-to that of the last commit with `git reset HEAD -- <file>`,
+to that of the last commit with `git restore --staged <file>`,
 which effectively reverts 'git add' and prevents the changes to
 this file from participating in the next commit.  After building
 the state to be committed incrementally with these commands,
diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index 774cecc7ed..6dcd39f6f6 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -214,6 +214,11 @@ symref::
 	`:lstrip` and `:rstrip` options in the same way as `refname`
 	above.
 
+worktreepath::
+	The absolute path to the worktree in which the ref is checked
+	out, if it is checked out in any linked worktree. Empty string
+	otherwise.
+
 In addition to the above, for commit and tag objects, the header
 field names (`tree`, `parent`, `object`, `type`, and `tag`) can
 be used to specify the value in the header field.
diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index 9ce5b8aaee..b9b97e63ae 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -426,8 +426,8 @@ One way to test if your MUA is set up correctly is:
 * Apply it:
 
     $ git fetch <project> master:test-apply
-    $ git checkout test-apply
-    $ git reset --hard
+    $ git switch test-apply
+    $ git restore --source=HEAD --staged --worktree :/
     $ git am a.patch
 
 If it does not apply correctly, there can be various reasons.
diff --git a/Documentation/git-hash-object.txt b/Documentation/git-hash-object.txt
index 814e74406a..df9e2c58bd 100644
--- a/Documentation/git-hash-object.txt
+++ b/Documentation/git-hash-object.txt
@@ -18,9 +18,7 @@ Computes the object ID value for an object with specified type
 with the contents of the named file (which can be outside of the
 work tree), and optionally writes the resulting object into the
 object database.  Reports its object ID to its standard output.
-This is used by 'git cvsimport' to update the index
-without modifying files in the work tree.  When <type> is not
-specified, it defaults to "blob".
+When <type> is not specified, it defaults to "blob".
 
 OPTIONS
 -------
diff --git a/Documentation/git-merge-base.txt b/Documentation/git-merge-base.txt
index 9f07f4f6ed..261d5c1164 100644
--- a/Documentation/git-merge-base.txt
+++ b/Documentation/git-merge-base.txt
@@ -149,7 +149,7 @@ instead.
 Discussion on fork-point mode
 -----------------------------
 
-After working on the `topic` branch created with `git checkout -b
+After working on the `topic` branch created with `git switch -c
 topic origin/master`, the history of remote-tracking branch
 `origin/master` may have been rewound and rebuilt, leading to a
 history of this shape:
diff --git a/Documentation/git-merge.txt b/Documentation/git-merge.txt
index c01cfa6595..01fd52dc70 100644
--- a/Documentation/git-merge.txt
+++ b/Documentation/git-merge.txt
@@ -13,8 +13,7 @@ SYNOPSIS
 	[-s <strategy>] [-X <strategy-option>] [-S[<keyid>]]
 	[--[no-]allow-unrelated-histories]
 	[--[no-]rerere-autoupdate] [-m <msg>] [-F <file>] [<commit>...]
-'git merge' --abort
-'git merge' --continue
+'git merge' (--continue | --abort | --quit)
 
 DESCRIPTION
 -----------
@@ -88,6 +87,11 @@ will be appended to the specified message.
 	Allow the rerere mechanism to update the index with the
 	result of auto-conflict resolution if possible.
 
+--overwrite-ignore::
+--no-overwrite-ignore::
+	Silently overwrite ignored files from the merge result. This
+	is the default behavior. Use `--no-overwrite-ignore` to abort.
+
 --abort::
 	Abort the current conflict resolution process, and
 	try to reconstruct the pre-merge state.
diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 5e4e927647..6156609cf7 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -12,12 +12,12 @@ SYNOPSIS
 	[<upstream> [<branch>]]
 'git rebase' [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
 	--root [<branch>]
-'git rebase' --continue | --skip | --abort | --quit | --edit-todo | --show-current-patch
+'git rebase' (--continue | --skip | --abort | --quit | --edit-todo | --show-current-patch)
 
 DESCRIPTION
 -----------
 If <branch> is specified, 'git rebase' will perform an automatic
-`git checkout <branch>` before doing anything else.  Otherwise
+`git switch <branch>` before doing anything else.  Otherwise
 it remains on the current branch.
 
 If <upstream> is not specified, the upstream configured in
diff --git a/Documentation/git-remote.txt b/Documentation/git-remote.txt
index 0cad37fb81..9659abbf8e 100644
--- a/Documentation/git-remote.txt
+++ b/Documentation/git-remote.txt
@@ -230,7 +230,7 @@ $ git branch -r
   staging/master
   staging/staging-linus
   staging/staging-next
-$ git checkout -b staging staging/master
+$ git switch -c staging staging/master
 ...
 ------------
 
diff --git a/Documentation/git-rerere.txt b/Documentation/git-rerere.txt
index 95763d7581..4cfc883378 100644
--- a/Documentation/git-rerere.txt
+++ b/Documentation/git-rerere.txt
@@ -91,7 +91,7 @@ For such a test, you need to merge master and topic somehow.
 One way to do it is to pull master into the topic branch:
 
 ------------
-	$ git checkout topic
+	$ git switch topic
 	$ git merge master
 
               o---*---o---+ topic
@@ -113,10 +113,10 @@ the upstream might have been advanced since the test merge `+`,
 in which case the final commit graph would look like this:
 
 ------------
-	$ git checkout topic
+	$ git switch topic
 	$ git merge master
 	$ ... work on both topic and master branches
-	$ git checkout master
+	$ git switch master
 	$ git merge topic
 
               o---*---o---+---o---o topic
@@ -136,11 +136,11 @@ merges, you could blow away the test merge, and keep building on
 top of the tip before the test merge:
 
 ------------
-	$ git checkout topic
+	$ git switch topic
 	$ git merge master
 	$ git reset --hard HEAD^ ;# rewind the test merge
 	$ ... work on both topic and master branches
-	$ git checkout master
+	$ git switch master
 	$ git merge topic
 
               o---*---o-------o---o topic
diff --git a/Documentation/git-reset.txt b/Documentation/git-reset.txt
index 26e746c53f..97e0544d9e 100644
--- a/Documentation/git-reset.txt
+++ b/Documentation/git-reset.txt
@@ -25,12 +25,13 @@ The `<tree-ish>`/`<commit>` defaults to `HEAD` in all forms.
 	the current branch.)
 +
 This means that `git reset <paths>` is the opposite of `git add
-<paths>`.
+<paths>`. This command is equivalent to
+`git restore [--source=<tree-ish>] --staged <paths>...`.
 +
 After running `git reset <paths>` to update the index entry, you can
-use linkgit:git-checkout[1] to check the contents out of the index to
-the working tree.
-Alternatively, using linkgit:git-checkout[1] and specifying a commit, you
+use linkgit:git-restore[1] to check the contents out of the index to
+the working tree. Alternatively, using linkgit:git-restore[1]
+and specifying a commit with `--source`, you
 can copy the contents of a path out of a commit to the index and to the
 working tree in one go.
 
@@ -86,8 +87,8 @@ but carries forward unmerged index entries.
 	changes, reset is aborted.
 --
 
-If you want to undo a commit other than the latest on a branch,
-linkgit:git-revert[1] is your friend.
+See "Reset, restore and revert" in linkgit:git[1] for the differences
+between the three commands.
 
 
 OPTIONS
@@ -149,9 +150,9 @@ See also the `--amend` option to linkgit:git-commit[1].
 Undo a commit, making it a topic branch::
 +
 ------------
-$ git branch topic/wip     <1>
-$ git reset --hard HEAD~3  <2>
-$ git checkout topic/wip   <3>
+$ git branch topic/wip          <1>
+$ git reset --hard HEAD~3       <2>
+$ git switch topic/wip          <3>
 ------------
 +
 <1> You have made some commits, but realize they were premature
@@ -232,13 +233,13 @@ working tree are not in any shape to be committed yet, but you
 need to get to the other branch for a quick bugfix.
 +
 ------------
-$ git checkout feature ;# you were working in "feature" branch and
-$ work work work       ;# got interrupted
+$ git switch feature  ;# you were working in "feature" branch and
+$ work work work      ;# got interrupted
 $ git commit -a -m "snapshot WIP"                 <1>
-$ git checkout master
+$ git switch master
 $ fix fix fix
 $ git commit ;# commit with real log
-$ git checkout feature
+$ git switch feature
 $ git reset --soft HEAD^ ;# go back to WIP state  <2>
 $ git reset                                       <3>
 ------------
@@ -279,18 +280,18 @@ reset it while keeping the changes in your working tree.
 +
 ------------
 $ git tag start
-$ git checkout -b branch1
+$ git switch -c branch1
 $ edit
 $ git commit ...                            <1>
 $ edit
-$ git checkout -b branch2                   <2>
+$ git switch -c branch2                     <2>
 $ git reset --keep start                    <3>
 ------------
 +
 <1> This commits your first edits in `branch1`.
 <2> In the ideal world, you could have realized that the earlier
     commit did not belong to the new topic when you created and switched
-    to `branch2` (i.e. `git checkout -b branch2 start`), but nobody is
+    to `branch2` (i.e. `git switch -c branch2 start`), but nobody is
     perfect.
 <3> But you can use `reset --keep` to remove the unwanted commit after
     you switched to `branch2`.
diff --git a/Documentation/git-restore.txt b/Documentation/git-restore.txt
new file mode 100644
index 0000000000..d90093f195
--- /dev/null
+++ b/Documentation/git-restore.txt
@@ -0,0 +1,185 @@
+git-restore(1)
+==============
+
+NAME
+----
+git-restore - Restore working tree files
+
+SYNOPSIS
+--------
+[verse]
+'git restore' [<options>] [--source=<tree>] [--staged] [--worktree] <pathspec>...
+'git restore' (-p|--patch) [<options>] [--source=<tree>] [--staged] [--worktree] [<pathspec>...]
+
+DESCRIPTION
+-----------
+Restore specified paths in the working tree with some contents from a
+restore source. If a path is tracked but does not exist in the restore
+source, it will be removed to match the source.
+
+The command can also be used to restore the content in the index with
+`--staged`, or restore both the working tree and the index with
+`--staged --worktree`.
+
+By default, the restore sources for working tree and the index are the
+index and `HEAD` respectively. `--source` could be used to specify a
+commit as the restore source.
+
+See "Reset, restore and revert" in linkgit:git[1] for the differences
+between the three commands.
+
+THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
+
+OPTIONS
+-------
+-s <tree>::
+--source=<tree>::
+	Restore the working tree files with the content from the given
+	tree. It is common to specify the source tree by naming a
+	commit, branch or tag associated with it.
++
+If not specified, the default restore source for the working tree is
+the index, and the default restore source for the index index is
+`HEAD`. When both `--staged` and `--worktree` are specified,
+`--source` must also be specified.
+
+-p::
+--patch::
+	Interactively select hunks in the difference between the
+	restore source and the restore location. See the ``Interactive
+	Mode'' section of linkgit:git-add[1] to learn how to operate
+	the `--patch` mode.
++
+Note that `--patch` can accept no pathspec and will prompt to restore
+all modified paths.
+
+-W::
+--worktree::
+-S::
+--staged::
+	Specify the restore location. If neither option is specified,
+	by default the working tree is restored. Specifying `--staged`
+	will only restore the index. Specifying both restores both.
+
+-q::
+--quiet::
+	Quiet, suppress feedback messages. Implies `--no-progress`.
+
+--progress::
+--no-progress::
+	Progress status is reported on the standard error stream
+	by default when it is attached to a terminal, unless `--quiet`
+	is specified. This flag enables progress reporting even if not
+	attached to a terminal, regardless of `--quiet`.
+
+--ours::
+--theirs::
+	When restoring files in the working tree from the index, use
+	stage #2 ('ours') or #3 ('theirs') for unmerged paths.
++
+Note that during `git rebase` and `git pull --rebase`, 'ours' and
+'theirs' may appear swapped. See the explanation of the same options
+in linkgit:git-checkout[1] for details.
+
+-m::
+--merge::
+	When restoring files on the working tree from the index,
+	recreate the conflicted merge in the unmerged paths.
+
+--conflict=<style>::
+	The same as `--merge` option above, but changes the way the
+	conflicting hunks are presented, overriding the
+	`merge.conflictStyle` configuration variable.  Possible values
+	are "merge" (default) and "diff3" (in addition to what is
+	shown by "merge" style, shows the original contents).
+
+--ignore-unmerged::
+	When restoring files on the working tree from the index, do
+	not abort the operation if there are unmerged entries and
+	neither `--ours`, `--theirs`, `--merge` or `--conflict` is
+	specified. Unmerged paths on the working tree are left alone.
+
+--ignore-skip-worktree-bits::
+	In sparse checkout mode, by default is to only update entries
+	matched by `<pathspec>` and sparse patterns in
+	$GIT_DIR/info/sparse-checkout. This option ignores the sparse
+	patterns and unconditionally restores any files in
+	`<pathspec>`.
+
+--overlay::
+--no-overlay::
+	In overlay mode, the command never removes files when
+	restoring. In no-overlay mode, tracked files that do not
+	appear in the `--source` tree are removed, to make them match
+	`<tree>` exactly. The default is no-overlay mode.
+
+EXAMPLES
+--------
+
+The following sequence switches to the `master` branch, reverts the
+`Makefile` to two revisions back, deletes hello.c by mistake, and gets
+it back from the index.
+
+------------
+$ git switch master
+$ git restore --source master~2 Makefile  <1>
+$ rm -f hello.c
+$ git restore hello.c                     <2>
+------------
+
+<1> take a file out of another commit
+<2> restore hello.c from the index
+
+If you want to restore _all_ C source files to match the version in
+the index, you can say
+
+------------
+$ git restore '*.c'
+------------
+
+Note the quotes around `*.c`.  The file `hello.c` will also be
+restored, even though it is no longer in the working tree, because the
+file globbing is used to match entries in the index (not in the
+working tree by the shell).
+
+To restore all files in the current directory
+
+------------
+$ git restore .
+------------
+
+or to restore all working tree files with 'top' pathspec magic (see
+linkgit:gitglossary[7])
+
+------------
+$ git restore :/
+------------
+
+To restore a file in the index to match the version in `HEAD` (this is
+the same as using linkgit:git-reset[1])
+
+------------
+$ git restore --staged hello.c
+------------
+
+or you can restore both the index and the working tree (this the same
+as using linkgit:git-checkout[1])
+
+------------
+$ git restore --source=HEAD --staged --worktree hello.c
+------------
+
+or the short form which is more practical but less readable:
+
+------------
+$ git restore -s@ -SW hello.c
+------------
+
+SEE ALSO
+--------
+linkgit:git-checkout[1],
+linkgit:git-reset[1]
+
+GIT
+---
+Part of the linkgit:git[1] suite
diff --git a/Documentation/git-rev-list.txt b/Documentation/git-rev-list.txt
index 88609ff435..9392760b25 100644
--- a/Documentation/git-rev-list.txt
+++ b/Documentation/git-rev-list.txt
@@ -48,6 +48,7 @@ SYNOPSIS
 	     [ --date=<format>]
 	     [ [ --objects | --objects-edge | --objects-edge-aggressive ]
 	       [ --unpacked ]
+	       [ --object-names | --no-object-names ]
 	       [ --filter=<filter-spec> [ --filter-print-omitted ] ] ]
 	     [ --missing=<missing-action> ]
 	     [ --pretty | --header ]
diff --git a/Documentation/git-revert.txt b/Documentation/git-revert.txt
index 0c82ca5bc0..fae4d66547 100644
--- a/Documentation/git-revert.txt
+++ b/Documentation/git-revert.txt
@@ -26,10 +26,13 @@ effect of some earlier commits (often only a faulty one).  If you want to
 throw away all uncommitted changes in your working directory, you
 should see linkgit:git-reset[1], particularly the `--hard` option.  If
 you want to extract specific files as they were in another commit, you
-should see linkgit:git-checkout[1], specifically the `git checkout
-<commit> -- <filename>` syntax.  Take care with these alternatives as
+should see linkgit:git-restore[1], specifically the `--source`
+option. Take care with these alternatives as
 both will discard uncommitted changes in your working directory.
 
+See "Reset, restore and revert" in linkgit:git[1] for the differences
+between the three commands.
+
 OPTIONS
 -------
 <commit>...::
diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt
index a861934c69..d93e5d0f58 100644
--- a/Documentation/git-send-email.txt
+++ b/Documentation/git-send-email.txt
@@ -508,8 +508,12 @@ app-specific or your regular password as appropriate.  If you have credential
 helper configured (see linkgit:git-credential[1]), the password will be saved in
 the credential store so you won't have to type it the next time.
 
-Note: the following perl modules are required
-      Net::SMTP::SSL, MIME::Base64 and Authen::SASL
+Note: the following core Perl modules that may be installed with your
+distribution of Perl are required:
+MIME::Base64, MIME::QuotedPrint, Net::Domain and Net::SMTP.
+These additional Perl modules are also required:
+Authen::SASL and Mail::Address.
+
 
 SEE ALSO
 --------
diff --git a/Documentation/git-stash.txt b/Documentation/git-stash.txt
index e31ea7d303..8fbe12c66c 100644
--- a/Documentation/git-stash.txt
+++ b/Documentation/git-stash.txt
@@ -235,12 +235,12 @@ return to your original branch to make the emergency fix, like this:
 +
 ----------------------------------------------------------------
 # ... hack hack hack ...
-$ git checkout -b my_wip
+$ git switch -c my_wip
 $ git commit -a -m "WIP"
-$ git checkout master
+$ git switch master
 $ edit emergency fix
 $ git commit -a -m "Fix in a hurry"
-$ git checkout my_wip
+$ git switch my_wip
 $ git reset --soft HEAD^
 # ... continue hacking ...
 ----------------------------------------------------------------
@@ -293,7 +293,8 @@ SEE ALSO
 linkgit:git-checkout[1],
 linkgit:git-commit[1],
 linkgit:git-reflog[1],
-linkgit:git-reset[1]
+linkgit:git-reset[1],
+linkgit:git-switch[1]
 
 GIT
 ---
diff --git a/Documentation/git-switch.txt b/Documentation/git-switch.txt
new file mode 100644
index 0000000000..197900363b
--- /dev/null
+++ b/Documentation/git-switch.txt
@@ -0,0 +1,273 @@
+git-switch(1)
+=============
+
+NAME
+----
+git-switch - Switch branches
+
+SYNOPSIS
+--------
+[verse]
+'git switch' [<options>] [--no-guess] <branch>
+'git switch' [<options>] --detach [<start-point>]
+'git switch' [<options>] (-c|-C) <new-branch> [<start-point>]
+'git switch' [<options>] --orphan <new-branch>
+
+DESCRIPTION
+-----------
+Switch to a specified branch. The working tree and the index are
+updated to match the branch. All new commits will be added to the tip
+of this branch.
+
+Optionally a new branch could be created with either `-c`, `-C`,
+automatically from a remote branch of same name (see `--guess`), or
+detach the working tree from any branch with `--detach`, along with
+switching.
+
+Switching branches does not require a clean index and working tree
+(i.e. no differences compared to `HEAD`). The operation is aborted
+however if the operation leads to loss of local changes, unless told
+otherwise with `--discard-changes` or `--merge`.
+
+THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
+
+OPTIONS
+-------
+<branch>::
+	Branch to switch to.
+
+<new-branch>::
+	Name for the new branch.
+
+<start-point>::
+	The starting point for the new branch. Specifying a
+	`<start-point>` allows you to create a branch based on some
+	other point in history than where HEAD currently points. (Or,
+	in the case of `--detach`, allows you to inspect and detach
+	from some other point.)
++
+You can use the `@{-N}` syntax to refer to the N-th last
+branch/commit switched to using "git switch" or "git checkout"
+operation. You may also specify `-` which is synonymous to `@{-1}`.
+This is often used to switch quickly between two branches, or to undo
+a branch switch by mistake.
++
+As a special case, you may use `A...B` as a shortcut for the merge
+base of `A` and `B` if there is exactly one merge base. You can leave
+out at most one of `A` and `B`, in which case it defaults to `HEAD`.
+
+-c <new-branch>::
+--create <new-branch>::
+	Create a new branch named `<new-branch>` starting at
+	`<start-point>` before switching to the branch. This is a
+	convenient shortcut for:
++
+------------
+$ git branch <new-branch>
+$ git switch <new-branch>
+------------
+
+-C <new-branch>::
+--force-create <new-branch>::
+	Similar to `--create` except that if `<new-branch>` already
+	exists, it will be reset to `<start-point>`. This is a
+	convenient shortcut for:
++
+------------
+$ git branch -f <new-branch>
+$ git switch <new-branch>
+------------
+
+-d::
+--detach::
+	Switch to a commit for inspection and discardable
+	experiments. See the "DETACHED HEAD" section in
+	linkgit:git-checkout[1] for details.
+
+--guess::
+--no-guess::
+	If `<branch>` is not found but there does exist a tracking
+	branch in exactly one remote (call it `<remote>`) with a
+	matching name, treat as equivalent to
++
+------------
+$ git switch -c <branch> --track <remote>/<branch>
+------------
++
+If the branch exists in multiple remotes and one of them is named by
+the `checkout.defaultRemote` configuration variable, we'll use that
+one for the purposes of disambiguation, even if the `<branch>` isn't
+unique across all remotes. Set it to e.g. `checkout.defaultRemote=origin`
+to always checkout remote branches from there if `<branch>` is
+ambiguous but exists on the 'origin' remote. See also
+`checkout.defaultRemote` in linkgit:git-config[1].
++
+`--guess` is the default behavior. Use `--no-guess` to disable it.
+
+-f::
+--force::
+	An alias for `--discard-changes`.
+
+--discard-changes::
+	Proceed even if the index or the working tree differs from
+	`HEAD`. Both the index and working tree are restored to match
+	the switching target. If `--recurse-submodules` is specified,
+	submodule content is also restored to match the switching
+	target. This is used to throw away local changes.
+
+-m::
+--merge::
+	If you have local modifications to one or more files that are
+	different between the current branch and the branch to which
+	you are switching, the command refuses to switch branches in
+	order to preserve your modifications in context.  However,
+	with this option, a three-way merge between the current
+	branch, your working tree contents, and the new branch is
+	done, and you will be on the new branch.
++
+When a merge conflict happens, the index entries for conflicting
+paths are left unmerged, and you need to resolve the conflicts
+and mark the resolved paths with `git add` (or `git rm` if the merge
+should result in deletion of the path).
+
+--conflict=<style>::
+	The same as `--merge` option above, but changes the way the
+	conflicting hunks are presented, overriding the
+	`merge.conflictStyle` configuration variable.  Possible values are
+	"merge" (default) and "diff3" (in addition to what is shown by
+	"merge" style, shows the original contents).
+
+-q::
+--quiet::
+	Quiet, suppress feedback messages.
+
+--progress::
+--no-progress::
+	Progress status is reported on the standard error stream
+	by default when it is attached to a terminal, unless `--quiet`
+	is specified. This flag enables progress reporting even if not
+	attached to a terminal, regardless of `--quiet`.
+
+-t::
+--track::
+	When creating a new branch, set up "upstream" configuration.
+	`-c` is implied. See `--track` in linkgit:git-branch[1] for
+	details.
++
+If no `-c` option is given, the name of the new branch will be derived
+from the remote-tracking branch, by looking at the local part of the
+refspec configured for the corresponding remote, and then stripping
+the initial part up to the "*".  This would tell us to use `hack` as
+the local branch when branching off of `origin/hack` (or
+`remotes/origin/hack`, or even `refs/remotes/origin/hack`).  If the
+given name has no slash, or the above guessing results in an empty
+name, the guessing is aborted.  You can explicitly give a name with
+`-c` in such a case.
+
+--no-track::
+	Do not set up "upstream" configuration, even if the
+	`branch.autoSetupMerge` configuration variable is true.
+
+--orphan <new-branch>::
+	Create a new 'orphan' branch, named `<new-branch>`. All
+	tracked files are removed.
+
+--ignore-other-worktrees::
+	`git switch` refuses when the wanted ref is already
+	checked out by another worktree. This option makes it check
+	the ref out anyway. In other words, the ref can be held by
+	more than one worktree.
+
+--recurse-submodules::
+--no-recurse-submodules::
+	Using `--recurse-submodules` will update the content of all
+	initialized submodules according to the commit recorded in the
+	superproject. If nothing (or `--no-recurse-submodules`) is
+	used, the work trees of submodules will not be updated. Just
+	like linkgit:git-submodule[1], this will detach `HEAD` of the
+	submodules.
+
+EXAMPLES
+--------
+
+The following command switches to the "master" branch:
+
+------------
+$ git switch master
+------------
+
+After working in the wrong branch, switching to the correct branch
+would be done using:
+
+------------
+$ git switch mytopic
+------------
+
+However, your "wrong" branch and correct "mytopic" branch may differ
+in files that you have modified locally, in which case the above
+switch would fail like this:
+
+------------
+$ git switch mytopic
+error: You have local changes to 'frotz'; not switching branches.
+------------
+
+You can give the `-m` flag to the command, which would try a three-way
+merge:
+
+------------
+$ git switch -m mytopic
+Auto-merging frotz
+------------
+
+After this three-way merge, the local modifications are _not_
+registered in your index file, so `git diff` would show you what
+changes you made since the tip of the new branch.
+
+To switch back to the previous branch before we switched to mytopic
+(i.e. "master" branch):
+
+------------
+$ git switch -
+------------
+
+You can grow a new branch from any commit. For example, switch to
+"HEAD~3" and create branch "fixup":
+
+------------
+$ git switch -c fixup HEAD~3
+Switched to a new branch 'fixup'
+------------
+
+If you want to start a new branch from a remote branch of the same
+name:
+
+------------
+$ git switch new-topic
+Branch 'new-topic' set up to track remote branch 'new-topic' from 'origin'
+Switched to a new branch 'new-topic'
+------------
+
+To check out commit `HEAD~3` for temporary inspection or experiment
+without creating a new branch:
+
+------------
+$ git switch --detach HEAD~3
+HEAD is now at 9fc9555312 Merge branch 'cc/shared-index-permbits'
+------------
+
+If it turns out whatever you have done is worth keeping, you can
+always create a new name for it (without switching away):
+
+------------
+$ git switch -c good-surprises
+------------
+
+SEE ALSO
+--------
+linkgit:git-checkout[1],
+linkgit:git-branch[1]
+
+GIT
+---
+Part of the linkgit:git[1] suite
diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index a74e7b926d..2e5599a67f 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -64,6 +64,13 @@ OPTIONS
 -s::
 --sign::
 	Make a GPG-signed tag, using the default e-mail address's key.
+	The default behavior of tag GPG-signing is controlled by `tag.gpgSign`
+	configuration variable if it exists, or disabled oder otherwise.
+	See linkgit:git-config[1].
+
+--no-sign::
+	Override `tag.gpgSign` configuration variable that is
+	set to force each and every tag to be signed.
 
 -u <keyid>::
 --local-user=<keyid>::
diff --git a/Documentation/git.txt b/Documentation/git.txt
index f9b09db89b..e095514ace 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -211,6 +211,26 @@ people via patch over e-mail.
 
 include::cmds-foreignscminterface.txt[]
 
+Reset, restore and revert
+~~~~~~~~~~~~~~~~~~~~~~~~~
+There are three commands with similar names: `git reset`,
+`git restore` and `git revert`.
+
+* linkgit:git-revert[1] is about making a new commit that reverts the
+  changes made by other commits.
+
+* linkgit:git-restore[1] is about restoring files in the working tree
+  from either the index or another commit. This command does not
+  update your branch. The command can also be used to restore files in
+  the index from another commit.
+
+* linkgit:git-reset[1] is about updating your branch, moving the tip
+  in order to add or remove commits from the branch. This operation
+  changes the commit history.
++
+`git reset` can also be used to restore the index, overlapping with
+`git restore`.
+
 
 Low-level commands (plumbing)
 -----------------------------
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index e387cc6dda..fb1d188d44 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -112,7 +112,8 @@ Checking-out and checking-in
 
 These attributes affect how the contents stored in the
 repository are copied to the working tree files when commands
-such as 'git checkout' and 'git merge' run.  They also affect how
+such as 'git switch', 'git checkout'  and 'git merge' run.
+They also affect how
 Git stores the contents you prepare in the working tree in the
 repository upon 'git add' and 'git commit'.
 
@@ -833,6 +834,8 @@ patterns are available:
 
 - `ruby` suitable for source code in the Ruby language.
 
+- `rust` suitable for source code in the Rust language.
+
 - `tex` suitable for source code for LaTeX documents.
 
 
diff --git a/Documentation/gitcli.txt b/Documentation/gitcli.txt
index 592e06d839..1ed3ca33b7 100644
--- a/Documentation/gitcli.txt
+++ b/Documentation/gitcli.txt
@@ -47,8 +47,8 @@ disambiguating `--` at appropriate places.
    things:
 +
 --------------------------------
-$ git checkout -- *.c
-$ git checkout -- \*.c
+$ git restore *.c
+$ git restore \*.c
 --------------------------------
 +
 The former lets your shell expand the fileglob, and you are asking
@@ -209,6 +209,18 @@ See also http://marc.info/?l=git&m=116563135620359 and
 http://marc.info/?l=git&m=119150393620273 for further
 information.
 
+Some other commands that also work on files in the working tree and/or
+in the index can take `--staged` and/or `--worktree`.
+
+* `--staged` is exactly like `--cached`, which is used to ask a
+  command to only work on the index, not the working tree.
+
+* `--worktree` is the opposite, to ask a command to work on the
+  working tree only, not the index.
+
+* The two options can be specified together to ask a command to work
+  on both the index and the working tree.
+
 GIT
 ---
 Part of the linkgit:git[1] suite
diff --git a/Documentation/gitcore-tutorial.txt b/Documentation/gitcore-tutorial.txt
index e29a9effcc..f880d21dfb 100644
--- a/Documentation/gitcore-tutorial.txt
+++ b/Documentation/gitcore-tutorial.txt
@@ -741,7 +741,7 @@ used earlier, and create a branch in it. You do that by simply just
 saying that you want to check out a new branch:
 
 ------------
-$ git checkout -b mybranch
+$ git switch -c mybranch
 ------------
 
 will create a new branch based at the current `HEAD` position, and switch
@@ -755,7 +755,7 @@ just telling 'git checkout' what the base of the checkout would be.
 In other words, if you have an earlier tag or branch, you'd just do
 
 ------------
-$ git checkout -b mybranch earlier-commit
+$ git switch -c mybranch earlier-commit
 ------------
 
 and it would create the new branch `mybranch` at the earlier commit,
@@ -765,7 +765,7 @@ and check out the state at that time.
 You can always just jump back to your original `master` branch by doing
 
 ------------
-$ git checkout master
+$ git switch master
 ------------
 
 (or any other branch-name, for that matter) and if you forget which
@@ -794,7 +794,7 @@ $ git branch <branchname> [startingpoint]
 
 which will simply _create_ the branch, but will not do anything further.
 You can then later -- once you decide that you want to actually develop
-on that branch -- switch to that branch with a regular 'git checkout'
+on that branch -- switch to that branch with a regular 'git switch'
 with the branchname as the argument.
 
 
@@ -808,7 +808,7 @@ being the same as the original `master` branch, let's make sure we're in
 that branch, and do some work there.
 
 ------------------------------------------------
-$ git checkout mybranch
+$ git switch mybranch
 $ echo "Work, work, work" >>hello
 $ git commit -m "Some work." -i hello
 ------------------------------------------------
@@ -825,7 +825,7 @@ does some work in the original branch, and simulate that by going back
 to the master branch, and editing the same file differently there:
 
 ------------
-$ git checkout master
+$ git switch master
 ------------
 
 Here, take a moment to look at the contents of `hello`, and notice how they
@@ -958,7 +958,7 @@ to the `master` branch. Let's go back to `mybranch`, and run
 'git merge' to get the "upstream changes" back to your branch.
 
 ------------
-$ git checkout mybranch
+$ git switch mybranch
 $ git merge -m "Merge upstream changes." master
 ------------
 
@@ -1133,9 +1133,8 @@ Remember, before running 'git merge', our `master` head was at
 work." commit.
 
 ------------
-$ git checkout mybranch
-$ git reset --hard master^2
-$ git checkout master
+$ git switch -C mybranch master^2
+$ git switch master
 $ git reset --hard master^
 ------------
 
diff --git a/Documentation/giteveryday.txt b/Documentation/giteveryday.txt
index 9f2528fc8c..1bd919f92b 100644
--- a/Documentation/giteveryday.txt
+++ b/Documentation/giteveryday.txt
@@ -41,7 +41,7 @@ following commands.
 
   * linkgit:git-log[1] to see what happened.
 
-  * linkgit:git-checkout[1] and linkgit:git-branch[1] to switch
+  * linkgit:git-switch[1] and linkgit:git-branch[1] to switch
     branches.
 
   * linkgit:git-add[1] to manage the index file.
@@ -51,8 +51,7 @@ following commands.
 
   * linkgit:git-commit[1] to advance the current branch.
 
-  * linkgit:git-reset[1] and linkgit:git-checkout[1] (with
-    pathname parameters) to undo changes.
+  * linkgit:git-restore[1] to undo changes.
 
   * linkgit:git-merge[1] to merge between local branches.
 
@@ -80,9 +79,9 @@ $ git tag v2.43 <2>
 Create a topic branch and develop.::
 +
 ------------
-$ git checkout -b alsa-audio <1>
+$ git switch -c alsa-audio <1>
 $ edit/compile/test
-$ git checkout -- curses/ux_audio_oss.c <2>
+$ git restore curses/ux_audio_oss.c <2>
 $ git add curses/ux_audio_alsa.c <3>
 $ edit/compile/test
 $ git diff HEAD <4>
@@ -90,7 +89,7 @@ $ git commit -a -s <5>
 $ edit/compile/test
 $ git diff HEAD^ <6>
 $ git commit -a --amend <7>
-$ git checkout master <8>
+$ git switch master <8>
 $ git merge alsa-audio <9>
 $ git log --since='3 days ago' <10>
 $ git log v2.43.. curses/ <11>
@@ -148,11 +147,11 @@ Clone the upstream and work on it.  Feed changes to upstream.::
 ------------
 $ git clone git://git.kernel.org/pub/scm/.../torvalds/linux-2.6 my2.6
 $ cd my2.6
-$ git checkout -b mine master <1>
+$ git switch -c mine master <1>
 $ edit/compile/test; git commit -a -s <2>
 $ git format-patch master <3>
 $ git send-email --to="person <email@example.com>" 00*.patch <4>
-$ git checkout master <5>
+$ git switch master <5>
 $ git pull <6>
 $ git log -p ORIG_HEAD.. arch/i386 include/asm-i386 <7>
 $ git ls-remote --heads http://git.kernel.org/.../jgarzik/libata-dev.git <8>
@@ -194,7 +193,7 @@ satellite$ edit/compile/test/commit
 satellite$ git push origin <4>
 
 mothership$ cd frotz
-mothership$ git checkout master
+mothership$ git switch master
 mothership$ git merge satellite/master <5>
 ------------
 +
@@ -216,7 +215,7 @@ machine into the master branch.
 Branch off of a specific tag.::
 +
 ------------
-$ git checkout -b private2.6.14 v2.6.14 <1>
+$ git switch -c private2.6.14 v2.6.14 <1>
 $ edit/compile/test; git commit -a
 $ git checkout master
 $ git cherry-pick v2.6.14..private2.6.14 <2>
@@ -274,14 +273,14 @@ $ mailx <3>
 & s 2 3 4 5 ./+to-apply
 & s 7 8 ./+hold-linus
 & q
-$ git checkout -b topic/one master
+$ git switch -c topic/one master
 $ git am -3 -i -s ./+to-apply <4>
 $ compile/test
-$ git checkout -b hold/linus && git am -3 -i -s ./+hold-linus <5>
-$ git checkout topic/one && git rebase master <6>
-$ git checkout pu && git reset --hard next <7>
+$ git switch -c hold/linus && git am -3 -i -s ./+hold-linus <5>
+$ git switch topic/one && git rebase master <6>
+$ git switch -C pu next <7>
 $ git merge topic/one topic/two && git merge hold/linus <8>
-$ git checkout maint
+$ git switch maint
 $ git cherry-pick master~4 <9>
 $ compile/test
 $ git tag -s -m "GIT 0.99.9x" v0.99.9x <10>
diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
index 786e778ab8..82cd573776 100644
--- a/Documentation/githooks.txt
+++ b/Documentation/githooks.txt
@@ -165,12 +165,13 @@ rebased, and is not set when rebasing the current branch.
 post-checkout
 ~~~~~~~~~~~~~
 
-This hook is invoked when a linkgit:git-checkout[1] is run after having updated the
+This hook is invoked when a linkgit:git-checkout[1] or
+linkgit:git-switch[1] is run after having updated the
 worktree.  The hook is given three parameters: the ref of the previous HEAD,
 the ref of the new HEAD (which may or may not have changed), and a flag
 indicating whether the checkout was a branch checkout (changing branches,
 flag=1) or a file checkout (retrieving a file from the index, flag=0).
-This hook cannot affect the outcome of `git checkout`.
+This hook cannot affect the outcome of `git switch` or `git checkout`.
 
 It is also run after linkgit:git-clone[1], unless the `--no-checkout` (`-n`) option is
 used. The first parameter given to the hook is the null-ref, the second the
@@ -406,7 +407,8 @@ exit with a zero status.
 For example, the hook can simply run `git read-tree -u -m HEAD "$1"`
 in order to emulate `git fetch` that is run in the reverse direction
 with `git push`, as the two-tree form of `git read-tree -u -m` is
-essentially the same as `git checkout` that switches branches while
+essentially the same as `git switch` or `git checkout`
+that switches branches while
 keeping the local changes in the working tree that do not interfere
 with the difference between the branches.
 
diff --git a/Documentation/gitignore.txt b/Documentation/gitignore.txt
index b5bc9dbff0..d47b1ae296 100644
--- a/Documentation/gitignore.txt
+++ b/Documentation/gitignore.txt
@@ -89,28 +89,28 @@ PATTERN FORMAT
    Put a backslash ("`\`") in front of the first "`!`" for patterns
    that begin with a literal "`!`", for example, "`\!important!.txt`".
 
- - If the pattern ends with a slash, it is removed for the
-   purpose of the following description, but it would only find
-   a match with a directory.  In other words, `foo/` will match a
-   directory `foo` and paths underneath it, but will not match a
-   regular file or a symbolic link `foo` (this is consistent
-   with the way how pathspec works in general in Git).
-
- - If the pattern does not contain a slash '/', Git treats it as
-   a shell glob pattern and checks for a match against the
-   pathname relative to the location of the `.gitignore` file
-   (relative to the toplevel of the work tree if not from a
-   `.gitignore` file).
-
- - Otherwise, Git treats the pattern as a shell glob: "`*`" matches
-   anything except "`/`", "`?`" matches any one character except "`/`"
-   and "`[]`" matches one character in a selected range. See
-   fnmatch(3) and the FNM_PATHNAME flag for a more detailed
-   description.
-
- - A leading slash matches the beginning of the pathname.
-   For example, "/{asterisk}.c" matches "cat-file.c" but not
-   "mozilla-sha1/sha1.c".
+ - The slash '/' is used as the directory separator. Separators may
+   occur at the beginning, middle or end of the `.gitignore` search pattern.
+
+ - If there is a separator at the beginning or middle (or both) of the
+   pattern, then the pattern is relative to the directory level of the
+   particular `.gitignore` file itself. Otherwise the pattern may also
+   match at any level below the `.gitignore` level.
+
+ - If there is a separator at the end of the pattern then the pattern
+   will only match directories, otherwise the pattern can match both
+   files and directories.
+
+ - For example, a pattern `doc/frotz/` matches `doc/frotz` directory,
+   but not `a/doc/frotz` directory; however `frotz/` matches `frotz`
+   and `a/frotz` that is a directory (all paths are relative from
+   the `.gitignore` file).
+
+ - An asterisk "`*`" matches anything except a slash.
+   The character "`?`" matches any one character except "`/`".
+   The range notation, e.g. `[a-zA-Z]`, can be used to match
+   one of the characters in a range. See fnmatch(3) and the
+   FNM_PATHNAME flag for a more detailed description.
 
 Two consecutive asterisks ("`**`") in patterns matched against
 full pathname may have special meaning:
@@ -152,6 +152,28 @@ To stop tracking a file that is currently tracked, use
 EXAMPLES
 --------
 
+ - The pattern `hello.*` matches any file or folder
+   whose name begins with `hello`. If one wants to restrict
+   this only to the directory and not in its subdirectories,
+   one can prepend the pattern with a slash, i.e. `/hello.*`;
+   the pattern now matches `hello.txt`, `hello.c` but not
+   `a/hello.java`.
+
+ - The pattern `foo/` will match a directory `foo` and
+   paths underneath it, but will not match a regular file
+   or a symbolic link `foo` (this is consistent with the
+   way how pathspec works in general in Git)
+
+ - The pattern `doc/frotz` and `/doc/frotz` have the same effect
+   in any `.gitignore` file. In other words, a leading slash
+   is not relevant  if there is already a middle slash in
+   the pattern.
+
+ - The pattern "foo/*", matches "foo/test.json"
+   (a regular file), "foo/bar" (a directory), but it does not match
+   "foo/bar/hello.c" (a regular file), as the asterisk in the
+   pattern does not match "bar/hello.c" which has a slash in it.
+
 --------------------------------------------------------------
     $ git status
     [...]
diff --git a/Documentation/gittutorial-2.txt b/Documentation/gittutorial-2.txt
index e0976f6017..8bdb7d0bd3 100644
--- a/Documentation/gittutorial-2.txt
+++ b/Documentation/gittutorial-2.txt
@@ -370,13 +370,13 @@ situation:
 $ git status
 On branch master
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   closing.txt
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   file.txt
 
diff --git a/Documentation/gittutorial.txt b/Documentation/gittutorial.txt
index 242de31cb6..59ef5cef1f 100644
--- a/Documentation/gittutorial.txt
+++ b/Documentation/gittutorial.txt
@@ -110,7 +110,7 @@ $ git status
 On branch master
 Changes to be committed:
 Your branch is up to date with 'origin/master'.
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   file1
 	modified:   file2
@@ -207,7 +207,7 @@ automatically.  The asterisk marks the branch you are currently on;
 type
 
 ------------------------------------------------
-$ git checkout experimental
+$ git switch experimental
 ------------------------------------------------
 
 to switch to the experimental branch.  Now edit a file, commit the
@@ -216,7 +216,7 @@ change, and switch back to the master branch:
 ------------------------------------------------
 (edit file)
 $ git commit -a
-$ git checkout master
+$ git switch master
 ------------------------------------------------
 
 Check that the change you made is no longer visible, since it was
diff --git a/Documentation/gitweb.txt b/Documentation/gitweb.txt
index c7436098c9..3cc9b034c4 100644
--- a/Documentation/gitweb.txt
+++ b/Documentation/gitweb.txt
@@ -28,8 +28,7 @@ Gitweb provides a web interface to Git repositories.  Its features include:
   revisions one at a time, viewing the history of the repository.
 * Finding commits which commit messages matches given search term.
 
-See http://git.kernel.org/?p=git/git.git;a=tree;f=gitweb[] or
-http://repo.or.cz/w/git.git/tree/HEAD:/gitweb/[] for gitweb source code,
+See http://repo.or.cz/w/git.git/tree/HEAD:/gitweb/[] for gitweb source code,
 browsed using gitweb itself.
 
 
diff --git a/Documentation/gitworkflows.txt b/Documentation/gitworkflows.txt
index ca11c7bdaf..abc0dc6bc7 100644
--- a/Documentation/gitworkflows.txt
+++ b/Documentation/gitworkflows.txt
@@ -301,8 +301,7 @@ topics on 'next':
 .Rewind and rebuild next
 [caption="Recipe: "]
 =====================================
-* `git checkout next`
-* `git reset --hard master`
+* `git switch -C next master`
 * `git merge ai/topic_in_next1`
 * `git merge ai/topic_in_next2`
 * ...
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 71a1fcc093..286fc163f1 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -708,6 +708,16 @@ ifdef::git-rev-list[]
 	Only useful with `--objects`; print the object IDs that are not
 	in packs.
 
+--object-names::
+	Only useful with `--objects`; print the names of the object IDs
+	that are found. This is the default behavior.
+
+--no-object-names::
+	Only useful with `--objects`; does not print the names of the object
+	IDs that are found. This inverts `--object-names`. This flag allows
+	the output to be more easily parsed by commands such as
+	linkgit:git-cat-file[1].
+
 --filter=<filter-spec>::
 	Only useful with one of the `--objects*`; omits objects (usually
 	blobs) from the list of printed objects.  The '<filter-spec>'
diff --git a/Documentation/revisions.txt b/Documentation/revisions.txt
index 82c1e5754e..97f995e5a9 100644
--- a/Documentation/revisions.txt
+++ b/Documentation/revisions.txt
@@ -115,7 +115,7 @@ Here's an example to make it more clear:
 ------------------------------
 $ git config push.default current
 $ git config remote.pushdefault myfork
-$ git checkout -b mybranch origin/master
+$ git switch -c mybranch origin/master
 
 $ git rev-parse --symbolic-full-name @{upstream}
 refs/remotes/origin/master
diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt
index 23c3cc7a37..f7ffe7d599 100644
--- a/Documentation/technical/api-trace2.txt
+++ b/Documentation/technical/api-trace2.txt
@@ -35,7 +35,7 @@ Format details are given in a later section.
 === The Normal Format Target
 
 The normal format target is a tradition printf format and similar
-to GIT_TRACE format.  This format is enabled with the `GIT_TR`
+to GIT_TRACE format.  This format is enabled with the `GIT_TRACE2`
 environment variable or the `trace2.normalTarget` system or global
 config setting.
 
diff --git a/Documentation/technical/commit-graph.txt b/Documentation/technical/commit-graph.txt
index 7805b0968c..fb53341d5e 100644
--- a/Documentation/technical/commit-graph.txt
+++ b/Documentation/technical/commit-graph.txt
@@ -127,23 +127,6 @@ Design Details
   helpful for these clones, anyway. The commit-graph will not be read or
   written when shallow commits are present.
 
-Future Work
------------
-
-- After computing and storing generation numbers, we must make graph
-  walks aware of generation numbers to gain the performance benefits they
-  enable. This will mostly be accomplished by swapping a commit-date-ordered
-  priority queue with one ordered by generation number. The following
-  operations are important candidates:
-
-    - 'log --topo-order'
-    - 'tag --merged'
-
-- A server could provide a commit-graph file as part of the network protocol
-  to avoid extra calculations by clients. This feature is only of benefit if
-  the user is willing to trust the file, because verifying the file is correct
-  is as hard as computing it from scratch.
-
 Related Links
 -------------
 [0] https://bugs.chromium.org/p/git/issues/detail?id=8
diff --git a/Documentation/user-manual.txt b/Documentation/user-manual.txt
index eff7890274..8bce75b2cf 100644
--- a/Documentation/user-manual.txt
+++ b/Documentation/user-manual.txt
@@ -122,10 +122,10 @@ Tags are expected to always point at the same version of a project,
 while heads are expected to advance as development progresses.
 
 Create a new branch head pointing to one of these versions and check it
-out using linkgit:git-checkout[1]:
+out using linkgit:git-switch[1]:
 
 ------------------------------------------------
-$ git checkout -b new v2.6.13
+$ git switch -c new v2.6.13
 ------------------------------------------------
 
 The working directory then reflects the contents that the project had
@@ -282,10 +282,10 @@ a summary of the commands:
 	this command will fail with a warning.
 `git branch -D <branch>`::
 	delete the branch `<branch>` irrespective of its merged status.
-`git checkout <branch>`::
+`git switch <branch>`::
 	make the current branch `<branch>`, updating the working
 	directory to reflect the version referenced by `<branch>`.
-`git checkout -b <new> <start-point>`::
+`git switch -c <new> <start-point>`::
 	create a new branch `<new>` referencing `<start-point>`, and
 	check it out.
 
@@ -302,22 +302,22 @@ ref: refs/heads/master
 Examining an old version without creating a new branch
 ------------------------------------------------------
 
-The `git checkout` command normally expects a branch head, but will also
-accept an arbitrary commit; for example, you can check out the commit
-referenced by a tag:
+The `git switch` command normally expects a branch head, but will also
+accept an arbitrary commit when invoked with --detach; for example,
+you can check out the commit referenced by a tag:
 
 ------------------------------------------------
-$ git checkout v2.6.17
+$ git switch --detach v2.6.17
 Note: checking out 'v2.6.17'.
 
 You are in 'detached HEAD' state. You can look around, make experimental
 changes and commit them, and you can discard any commits you make in this
-state without impacting any branches by performing another checkout.
+state without impacting any branches by performing another switch.
 
 If you want to create a new branch to retain commits you create, you may
-do so (now or later) by using -b with the checkout command again. Example:
+do so (now or later) by using -c with the switch command again. Example:
 
-  git checkout -b new_branch_name
+  git switch -c new_branch_name
 
 HEAD is now at 427abfa Linux v2.6.17
 ------------------------------------------------
@@ -373,7 +373,7 @@ You might want to build on one of these remote-tracking branches
 on a branch of your own, just as you would for a tag:
 
 ------------------------------------------------
-$ git checkout -b my-todo-copy origin/todo
+$ git switch -c my-todo-copy origin/todo
 ------------------------------------------------
 
 You can also check out `origin/todo` directly to examine it or
@@ -1408,7 +1408,7 @@ If you get stuck and decide to just give up and throw the whole mess
 away, you can always return to the pre-merge state with
 
 -------------------------------------------------
-$ git reset --hard HEAD
+$ git merge --abort
 -------------------------------------------------
 
 Or, if you've already committed the merge that you want to throw away,
@@ -1446,7 +1446,7 @@ mistake, you can return the entire working tree to the last committed
 state with
 
 -------------------------------------------------
-$ git reset --hard HEAD
+$ git restore --staged --worktree :/
 -------------------------------------------------
 
 If you make a commit that you later wish you hadn't, there are two
@@ -1523,12 +1523,10 @@ Checking out an old version of a file
 
 In the process of undoing a previous bad change, you may find it
 useful to check out an older version of a particular file using
-linkgit:git-checkout[1].  We've used `git checkout` before to switch
-branches, but it has quite different behavior if it is given a path
-name: the command
+linkgit:git-restore[1]. The command
 
 -------------------------------------------------
-$ git checkout HEAD^ path/to/file
+$ git restore --source=HEAD^ path/to/file
 -------------------------------------------------
 
 replaces path/to/file by the contents it had in the commit HEAD^, and
@@ -2211,8 +2209,8 @@ $ git branch --track release origin/master
 These can be easily kept up to date using linkgit:git-pull[1].
 
 -------------------------------------------------
-$ git checkout test && git pull
-$ git checkout release && git pull
+$ git switch test && git pull
+$ git switch release && git pull
 -------------------------------------------------
 
 Important note!  If you have any local changes in these branches, then
@@ -2264,7 +2262,7 @@ tested changes
 2) help future bug hunters that use `git bisect` to find problems
 
 -------------------------------------------------
-$ git checkout -b speed-up-spinlocks v2.6.35
+$ git switch -c speed-up-spinlocks v2.6.35
 -------------------------------------------------
 
 Now you apply the patch(es), run some tests, and commit the change(s).  If
@@ -2279,7 +2277,7 @@ When you are happy with the state of this change, you can merge it into the
 "test" branch in preparation to make it public:
 
 -------------------------------------------------
-$ git checkout test && git merge speed-up-spinlocks
+$ git switch test && git merge speed-up-spinlocks
 -------------------------------------------------
 
 It is unlikely that you would have any conflicts here ... but you might if you
@@ -2291,7 +2289,7 @@ see the value of keeping each patch (or patch series) in its own branch.  It
 means that the patches can be moved into the `release` tree in any order.
 
 -------------------------------------------------
-$ git checkout release && git merge speed-up-spinlocks
+$ git switch release && git merge speed-up-spinlocks
 -------------------------------------------------
 
 After a while, you will have a number of branches, and despite the
@@ -2512,7 +2510,7 @@ Suppose that you create a branch `mywork` on a remote-tracking branch
 `origin`, and create some commits on top of it:
 
 -------------------------------------------------
-$ git checkout -b mywork origin
+$ git switch -c mywork origin
 $ vi file.txt
 $ git commit
 $ vi otherfile.txt
@@ -2552,7 +2550,7 @@ commits without any merges, you may instead choose to use
 linkgit:git-rebase[1]:
 
 -------------------------------------------------
-$ git checkout mywork
+$ git switch mywork
 $ git rebase origin
 -------------------------------------------------
 
@@ -3668,13 +3666,13 @@ change within the submodule, and then update the superproject to reference the
 new commit:
 
 -------------------------------------------------
-$ git checkout master
+$ git switch master
 -------------------------------------------------
 
 or
 
 -------------------------------------------------
-$ git checkout -b fix-up
+$ git switch -c fix-up
 -------------------------------------------------
 
 then
@@ -3800,8 +3798,8 @@ use linkgit:git-tag[1] for both.
 The Workflow
 ------------
 
-High-level operations such as linkgit:git-commit[1],
-linkgit:git-checkout[1] and linkgit:git-reset[1] work by moving data
+High-level operations such as linkgit:git-commit[1] and
+linkgit:git-restore[1] work by moving data
 between the working tree, the index, and the object database.  Git
 provides low-level operations which perform each of these steps
 individually.
@@ -4194,7 +4192,7 @@ start.
 A good place to start is with the contents of the initial commit, with:
 
 ----------------------------------------------------
-$ git checkout e83c5163
+$ git switch --detach e83c5163
 ----------------------------------------------------
 
 The initial revision lays the foundation for almost everything Git has
@@ -4437,10 +4435,10 @@ Managing branches
 -----------------
 
 -----------------------------------------------
-$ git branch	     # list all local branches in this repo
-$ git checkout test  # switch working directory to branch "test"
-$ git branch new     # create branch "new" starting at current HEAD
-$ git branch -d new  # delete branch "new"
+$ git branch			# list all local branches in this repo
+$ git switch test	        # switch working directory to branch "test"
+$ git branch new		# create branch "new" starting at current HEAD
+$ git branch -d new		# delete branch "new"
 -----------------------------------------------
 
 Instead of basing a new branch on current HEAD (the default), use:
@@ -4456,7 +4454,7 @@ $ git branch new test~10 # ten commits before tip of branch "test"
 Create and switch to a new branch at the same time:
 
 -----------------------------------------------
-$ git checkout -b new v2.6.15
+$ git switch -c new v2.6.15
 -----------------------------------------------
 
 Update and examine branches from the repository you cloned from:
@@ -4467,7 +4465,7 @@ $ git branch -r		# list
   origin/master
   origin/next
   ...
-$ git checkout -b masterwork origin/master
+$ git switch -c masterwork origin/master
 -----------------------------------------------
 
 Fetch a branch from a different repository, and give it a new
diff --git a/Makefile b/Makefile
index f58bf14c7b..98a0588416 100644
--- a/Makefile
+++ b/Makefile
@@ -771,9 +771,11 @@ BUILT_INS += git-format-patch$X
 BUILT_INS += git-fsck-objects$X
 BUILT_INS += git-init$X
 BUILT_INS += git-merge-subtree$X
+BUILT_INS += git-restore$X
 BUILT_INS += git-show$X
 BUILT_INS += git-stage$X
 BUILT_INS += git-status$X
+BUILT_INS += git-switch$X
 BUILT_INS += git-whatchanged$X
 
 # what 'all' will build and 'install' will install in gitexecdir,
@@ -1235,7 +1237,7 @@ endif
 
 ifdef SANE_TOOL_PATH
 SANE_TOOL_PATH_SQ = $(subst ','\'',$(SANE_TOOL_PATH))
-BROKEN_PATH_FIX = 's|^\# @@BROKEN_PATH_FIX@@$$|git_broken_path_fix $(SANE_TOOL_PATH_SQ)|'
+BROKEN_PATH_FIX = 's|^\# @@BROKEN_PATH_FIX@@$$|git_broken_path_fix "$(SANE_TOOL_PATH_SQ)"|'
 PATH := $(SANE_TOOL_PATH):${PATH}
 else
 BROKEN_PATH_FIX = '/^\# @@BROKEN_PATH_FIX@@$$/d'
@@ -2858,6 +2860,33 @@ install: all
 	$(INSTALL) $(ALL_PROGRAMS) '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
 	$(INSTALL) -m 644 $(SCRIPT_LIB) '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
 	$(INSTALL) $(install_bindir_programs) '$(DESTDIR_SQ)$(bindir_SQ)'
+ifdef MSVC
+	# We DO NOT install the individual foo.o.pdb files because they
+	# have already been rolled up into the exe's pdb file.
+	# We DO NOT have pdb files for the builtin commands (like git-status.exe)
+	# because it is just a copy/hardlink of git.exe, rather than a unique binary.
+	$(INSTALL) git.pdb '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) git-shell.pdb '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) git-upload-pack.pdb '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) git-credential-store.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-daemon.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-fast-import.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-http-backend.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-http-fetch.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-http-push.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-imap-send.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-remote-http.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-remote-testsvn.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-sh-i18n--envsubst.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+	$(INSTALL) git-show-index.pdb '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
+ifndef DEBUG
+	$(INSTALL) $(vcpkg_rel_bin)/*.dll '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) $(vcpkg_rel_bin)/*.pdb '$(DESTDIR_SQ)$(bindir_SQ)'
+else
+	$(INSTALL) $(vcpkg_dbg_bin)/*.dll '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) $(vcpkg_dbg_bin)/*.pdb '$(DESTDIR_SQ)$(bindir_SQ)'
+endif
+endif
 	$(MAKE) -C templates DESTDIR='$(DESTDIR_SQ)' install
 	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(mergetools_instdir_SQ)'
 	$(INSTALL) -m 644 mergetools/* '$(DESTDIR_SQ)$(mergetools_instdir_SQ)'
@@ -3070,6 +3099,19 @@ endif
 	$(RM) GIT-VERSION-FILE GIT-CFLAGS GIT-LDFLAGS GIT-BUILD-OPTIONS
 	$(RM) GIT-USER-AGENT GIT-PREFIX
 	$(RM) GIT-SCRIPT-DEFINES GIT-PERL-DEFINES GIT-PERL-HEADER GIT-PYTHON-VARS
+ifdef MSVC
+	$(RM) $(patsubst %.o,%.o.pdb,$(OBJECTS))
+	$(RM) $(patsubst %.exe,%.pdb,$(OTHER_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.iobj,$(OTHER_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ipdb,$(OTHER_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.pdb,$(PROGRAMS))
+	$(RM) $(patsubst %.exe,%.iobj,$(PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ipdb,$(PROGRAMS))
+	$(RM) $(patsubst %.exe,%.pdb,$(TEST_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.iobj,$(TEST_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ipdb,$(TEST_PROGRAMS))
+	$(RM) compat/vcbuild/MSVC-DEFS-GEN
+endif
 
 .PHONY: all install profile-clean cocciclean clean strip
 .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
diff --git a/advice.c b/advice.c
index 4b283be51a..67de6dece4 100644
--- a/advice.c
+++ b/advice.c
@@ -13,6 +13,7 @@ int advice_push_needs_force = 1;
 int advice_push_unqualified_ref_name = 1;
 int advice_status_hints = 1;
 int advice_status_u_option = 1;
+int advice_status_ahead_behind_warning = 1;
 int advice_commit_before_merge = 1;
 int advice_reset_quiet_warning = 1;
 int advice_resolve_conflict = 1;
@@ -70,6 +71,7 @@ static struct {
 	{ "pushUnqualifiedRefName", &advice_push_unqualified_ref_name },
 	{ "statusHints", &advice_status_hints },
 	{ "statusUoption", &advice_status_u_option },
+	{ "statusAheadBehindWarning", &advice_status_ahead_behind_warning },
 	{ "commitBeforeMerge", &advice_commit_before_merge },
 	{ "resetQuiet", &advice_reset_quiet_warning },
 	{ "resolveConflict", &advice_resolve_conflict },
@@ -195,13 +197,22 @@ void NORETURN die_conclude_merge(void)
 void detach_advice(const char *new_name)
 {
 	const char *fmt =
-	_("Note: checking out '%s'.\n\n"
+	_("Note: switching to '%s'.\n"
+	"\n"
 	"You are in 'detached HEAD' state. You can look around, make experimental\n"
 	"changes and commit them, and you can discard any commits you make in this\n"
-	"state without impacting any branches by performing another checkout.\n\n"
+	"state without impacting any branches by switching back to a branch.\n"
+	"\n"
 	"If you want to create a new branch to retain commits you create, you may\n"
-	"do so (now or later) by using -b with the checkout command again. Example:\n\n"
-	"  git checkout -b <new-branch-name>\n\n");
+	"do so (now or later) by using -c with the switch command. Example:\n"
+	"\n"
+	"  git switch -c <new-branch-name>\n"
+	"\n"
+	"Or undo this operation with:\n"
+	"\n"
+	"  git switch -\n"
+	"\n"
+	"Turn off this advice by setting config variable advice.detachedHead to false\n\n");
 
 	fprintf(stderr, fmt, new_name);
 }
diff --git a/advice.h b/advice.h
index 495e53255c..940c4c253e 100644
--- a/advice.h
+++ b/advice.h
@@ -13,6 +13,7 @@ extern int advice_push_needs_force;
 extern int advice_push_unqualified_ref_name;
 extern int advice_status_hints;
 extern int advice_status_u_option;
+extern int advice_status_ahead_behind_warning;
 extern int advice_commit_before_merge;
 extern int advice_reset_quiet_warning;
 extern int advice_resolve_conflict;
diff --git a/blob.c b/blob.c
index 342bdbb1bb..36f9abda19 100644
--- a/blob.c
+++ b/blob.c
@@ -7,10 +7,9 @@ const char *blob_type = "blob";
 
 struct blob *lookup_blob(struct repository *r, const struct object_id *oid)
 {
-	struct object *obj = lookup_object(r, oid->hash);
+	struct object *obj = lookup_object(r, oid);
 	if (!obj)
-		return create_object(r, oid->hash,
-				     alloc_blob_node(r));
+		return create_object(r, oid, alloc_blob_node(r));
 	return object_as_type(r, obj, OBJ_BLOB, 0);
 }
 
diff --git a/branch.c b/branch.c
index e70838fb87..579494738a 100644
--- a/branch.c
+++ b/branch.c
@@ -346,9 +346,9 @@ void remove_merge_branch_state(struct repository *r)
 	unlink(git_path_merge_mode(r));
 }
 
-void remove_branch_state(struct repository *r)
+void remove_branch_state(struct repository *r, int verbose)
 {
-	sequencer_post_commit_cleanup(r);
+	sequencer_post_commit_cleanup(r, verbose);
 	unlink(git_path_squash_msg(r));
 	remove_merge_branch_state(r);
 }
diff --git a/branch.h b/branch.h
index 064ee576f2..df0be61506 100644
--- a/branch.h
+++ b/branch.h
@@ -70,7 +70,7 @@ void remove_merge_branch_state(struct repository *r);
  * Remove information about the state of working on the current
  * branch. (E.g., MERGE_HEAD)
  */
-void remove_branch_state(struct repository *r);
+void remove_branch_state(struct repository *r, int verbose);
 
 /*
  * Configure local branch "local" as downstream to branch "remote"
diff --git a/builtin.h b/builtin.h
index ec7e0954c4..3d449a0210 100644
--- a/builtin.h
+++ b/builtin.h
@@ -214,6 +214,7 @@ int cmd_remote_fd(int argc, const char **argv, const char *prefix);
 int cmd_repack(int argc, const char **argv, const char *prefix);
 int cmd_rerere(int argc, const char **argv, const char *prefix);
 int cmd_reset(int argc, const char **argv, const char *prefix);
+int cmd_restore(int argc, const char **argv, const char *prefix);
 int cmd_rev_list(int argc, const char **argv, const char *prefix);
 int cmd_rev_parse(int argc, const char **argv, const char *prefix);
 int cmd_revert(int argc, const char **argv, const char *prefix);
@@ -227,6 +228,7 @@ int cmd_status(int argc, const char **argv, const char *prefix);
 int cmd_stash(int argc, const char **argv, const char *prefix);
 int cmd_stripspace(int argc, const char **argv, const char *prefix);
 int cmd_submodule__helper(int argc, const char **argv, const char *prefix);
+int cmd_switch(int argc, const char **argv, const char *prefix);
 int cmd_symbolic_ref(int argc, const char **argv, const char *prefix);
 int cmd_tag(int argc, const char **argv, const char *prefix);
 int cmd_tar_tree(int argc, const char **argv, const char *prefix);
diff --git a/builtin/am.c b/builtin/am.c
index 78389d08b6..1aea657a7f 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1801,7 +1801,7 @@ static void am_run(struct am_state *state, int resume)
 	 */
 	if (!state->rebasing) {
 		am_destroy(state);
-		close_all_packs(the_repository->objects);
+		close_object_store(the_repository->objects);
 		run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 	}
 }
@@ -1956,7 +1956,7 @@ static int clean_index(const struct object_id *head, const struct object_id *rem
 	if (merge_tree(remote_tree))
 		return -1;
 
-	remove_branch_state(the_repository);
+	remove_branch_state(the_repository, 0);
 
 	return 0;
 }
diff --git a/builtin/blame.c b/builtin/blame.c
index 21cde57e71..50e3d4a265 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -59,8 +59,8 @@ static size_t blame_date_width;
 
 static struct string_list mailmap = STRING_LIST_INIT_NODUP;
 
-#ifndef DEBUG
-#define DEBUG 0
+#ifndef DEBUG_BLAME
+#define DEBUG_BLAME 0
 #endif
 
 static unsigned blame_move_score;
@@ -1062,7 +1062,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 	if (blame_copy_score)
 		sb.copy_score = blame_copy_score;
 
-	sb.debug = DEBUG;
+	sb.debug = DEBUG_BLAME;
 	sb.on_sanity_fail = &sanity_check_on_fail;
 
 	sb.show_root = show_root;
diff --git a/builtin/branch.c b/builtin/branch.c
index d4359b33ac..2ef214632f 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -47,6 +47,7 @@ static char branch_colors[][COLOR_MAXLEN] = {
 	GIT_COLOR_NORMAL,       /* LOCAL */
 	GIT_COLOR_GREEN,        /* CURRENT */
 	GIT_COLOR_BLUE,         /* UPSTREAM */
+	GIT_COLOR_CYAN,         /* WORKTREE */
 };
 enum color_branch {
 	BRANCH_COLOR_RESET = 0,
@@ -54,7 +55,8 @@ enum color_branch {
 	BRANCH_COLOR_REMOTE = 2,
 	BRANCH_COLOR_LOCAL = 3,
 	BRANCH_COLOR_CURRENT = 4,
-	BRANCH_COLOR_UPSTREAM = 5
+	BRANCH_COLOR_UPSTREAM = 5,
+	BRANCH_COLOR_WORKTREE = 6
 };
 
 static const char *color_branch_slots[] = {
@@ -64,6 +66,7 @@ static const char *color_branch_slots[] = {
 	[BRANCH_COLOR_LOCAL]	= "local",
 	[BRANCH_COLOR_CURRENT]	= "current",
 	[BRANCH_COLOR_UPSTREAM] = "upstream",
+	[BRANCH_COLOR_WORKTREE] = "worktree",
 };
 
 static struct string_list output = STRING_LIST_INIT_DUP;
@@ -342,9 +345,10 @@ static char *build_format(struct ref_filter *filter, int maxwidth, const char *r
 	struct strbuf local = STRBUF_INIT;
 	struct strbuf remote = STRBUF_INIT;
 
-	strbuf_addf(&local, "%%(if)%%(HEAD)%%(then)* %s%%(else)  %s%%(end)",
-		    branch_get_color(BRANCH_COLOR_CURRENT),
-		    branch_get_color(BRANCH_COLOR_LOCAL));
+	strbuf_addf(&local, "%%(if)%%(HEAD)%%(then)* %s%%(else)%%(if)%%(worktreepath)%%(then)+ %s%%(else)  %s%%(end)%%(end)",
+			branch_get_color(BRANCH_COLOR_CURRENT),
+			branch_get_color(BRANCH_COLOR_WORKTREE),
+			branch_get_color(BRANCH_COLOR_LOCAL));
 	strbuf_addf(&remote, "  %s",
 		    branch_get_color(BRANCH_COLOR_REMOTE));
 
@@ -363,9 +367,13 @@ static char *build_format(struct ref_filter *filter, int maxwidth, const char *r
 		strbuf_addf(&local, " %s ", obname.buf);
 
 		if (filter->verbose > 1)
+		{
+			strbuf_addf(&local, "%%(if:notequals=*)%%(HEAD)%%(then)%%(if)%%(worktreepath)%%(then)(%s%%(worktreepath)%s) %%(end)%%(end)",
+				    branch_get_color(BRANCH_COLOR_WORKTREE), branch_get_color(BRANCH_COLOR_RESET));
 			strbuf_addf(&local, "%%(if)%%(upstream)%%(then)[%s%%(upstream:short)%s%%(if)%%(upstream:track)"
 				    "%%(then): %%(upstream:track,nobracket)%%(end)] %%(end)%%(contents:subject)",
 				    branch_get_color(BRANCH_COLOR_UPSTREAM), branch_get_color(BRANCH_COLOR_RESET));
+		}
 		else
 			strbuf_addf(&local, "%%(if)%%(upstream:track)%%(then)%%(upstream:track) %%(end)%%(contents:subject)");
 
@@ -830,7 +838,8 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		strbuf_release(&buf);
 	} else if (argc > 0 && argc <= 2) {
 		if (filter.kind != FILTER_REFS_BRANCHES)
-			die(_("-a and -r options to 'git branch' do not make sense with a branch name"));
+			die(_("The -a, and -r, options to 'git branch' do not take a branch name.\n"
+				  "Did you mean to use: -a|-r --list <pattern>?"));
 
 		if (track == BRANCH_TRACK_OVERRIDE)
 			die(_("the '--set-upstream' option is no longer supported. Please use '--track' or '--set-upstream-to' instead."));
diff --git a/builtin/checkout.c b/builtin/checkout.c
index ffa776c6e1..91f8509f85 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -1,32 +1,31 @@
 #define USE_THE_INDEX_COMPATIBILITY_MACROS
 #include "builtin.h"
-#include "config.h"
+#include "advice.h"
+#include "blob.h"
+#include "branch.h"
+#include "cache-tree.h"
 #include "checkout.h"
+#include "commit.h"
+#include "config.h"
+#include "diff.h"
+#include "dir.h"
+#include "ll-merge.h"
 #include "lockfile.h"
+#include "merge-recursive.h"
+#include "object-store.h"
 #include "parse-options.h"
 #include "refs.h"
-#include "object-store.h"
-#include "commit.h"
+#include "remote.h"
+#include "resolve-undo.h"
+#include "revision.h"
+#include "run-command.h"
+#include "submodule.h"
+#include "submodule-config.h"
 #include "tree.h"
 #include "tree-walk.h"
-#include "cache-tree.h"
 #include "unpack-trees.h"
-#include "dir.h"
-#include "run-command.h"
-#include "merge-recursive.h"
-#include "branch.h"
-#include "diff.h"
-#include "revision.h"
-#include "remote.h"
-#include "blob.h"
+#include "wt-status.h"
 #include "xdiff-interface.h"
-#include "ll-merge.h"
-#include "resolve-undo.h"
-#include "submodule-config.h"
-#include "submodule.h"
-#include "advice.h"
-
-static int checkout_optimize_new_branch;
 
 static const char * const checkout_usage[] = {
 	N_("git checkout [<options>] <branch>"),
@@ -34,12 +33,23 @@ static const char * const checkout_usage[] = {
 	NULL,
 };
 
+static const char * const switch_branch_usage[] = {
+	N_("git switch [<options>] [<branch>]"),
+	NULL,
+};
+
+static const char * const restore_usage[] = {
+	N_("git restore [<options>] [--source=<branch>] <file>..."),
+	NULL,
+};
+
 struct checkout_opts {
 	int patch_mode;
 	int quiet;
 	int merge;
 	int force;
 	int force_detach;
+	int implicit_detach;
 	int writeout_stage;
 	int overwrite_ignore;
 	int ignore_skipworktree;
@@ -47,10 +57,19 @@ struct checkout_opts {
 	int show_progress;
 	int count_checkout_paths;
 	int overlay_mode;
-	/*
-	 * If new checkout options are added, skip_merge_working_tree
-	 * should be updated accordingly.
-	 */
+	int dwim_new_local_branch;
+	int discard_changes;
+	int accept_ref;
+	int accept_pathspec;
+	int switch_branch_doing_nothing_is_ok;
+	int only_merge_on_switching_branches;
+	int can_switch_when_in_progress;
+	int orphan_from_empty_tree;
+	int empty_pathspec_ok;
+	int checkout_index;
+	int checkout_worktree;
+	const char *ignore_unmerged_opt;
+	int ignore_unmerged;
 
 	const char *new_branch;
 	const char *new_branch_force;
@@ -58,10 +77,12 @@ struct checkout_opts {
 	int new_branch_log;
 	enum branch_track track;
 	struct diff_options diff_options;
+	char *conflict_style;
 
 	int branch_exists;
 	const char *prefix;
 	struct pathspec pathspec;
+	const char *from_treeish;
 	struct tree *source_tree;
 };
 
@@ -313,17 +334,74 @@ static void mark_ce_for_checkout_no_overlay(struct cache_entry *ce,
 	}
 }
 
+static int checkout_worktree(const struct checkout_opts *opts)
+{
+	struct checkout state = CHECKOUT_INIT;
+	int nr_checkouts = 0, nr_unmerged = 0;
+	int errs = 0;
+	int pos;
+
+	state.force = 1;
+	state.refresh_cache = 1;
+	state.istate = &the_index;
+
+	enable_delayed_checkout(&state);
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		if (ce->ce_flags & CE_MATCHED) {
+			if (!ce_stage(ce)) {
+				errs |= checkout_entry(ce, &state,
+						       NULL, &nr_checkouts);
+				continue;
+			}
+			if (opts->writeout_stage)
+				errs |= checkout_stage(opts->writeout_stage,
+						       ce, pos,
+						       &state,
+						       &nr_checkouts, opts->overlay_mode);
+			else if (opts->merge)
+				errs |= checkout_merged(pos, &state,
+							&nr_unmerged);
+			pos = skip_same_name(ce, pos) - 1;
+		}
+	}
+	remove_marked_cache_entries(&the_index, 1);
+	remove_scheduled_dirs();
+	errs |= finish_delayed_checkout(&state, &nr_checkouts);
+
+	if (opts->count_checkout_paths) {
+		if (nr_unmerged)
+			fprintf_ln(stderr, Q_("Recreated %d merge conflict",
+					      "Recreated %d merge conflicts",
+					      nr_unmerged),
+				   nr_unmerged);
+		if (opts->source_tree)
+			fprintf_ln(stderr, Q_("Updated %d path from %s",
+					      "Updated %d paths from %s",
+					      nr_checkouts),
+				   nr_checkouts,
+				   find_unique_abbrev(&opts->source_tree->object.oid,
+						      DEFAULT_ABBREV));
+		else if (!nr_unmerged || nr_checkouts)
+			fprintf_ln(stderr, Q_("Updated %d path from the index",
+					      "Updated %d paths from the index",
+					      nr_checkouts),
+				   nr_checkouts);
+	}
+
+	return errs;
+}
+
 static int checkout_paths(const struct checkout_opts *opts,
 			  const char *revision)
 {
 	int pos;
-	struct checkout state = CHECKOUT_INIT;
 	static char *ps_matched;
 	struct object_id rev;
 	struct commit *head;
 	int errs = 0;
 	struct lock_file lock_file = LOCK_INIT;
-	int nr_checkouts = 0, nr_unmerged = 0;
+	int checkout_index;
 
 	trace2_cmd_mode(opts->patch_mode ? "patch" : "path");
 
@@ -333,8 +411,9 @@ static int checkout_paths(const struct checkout_opts *opts,
 	if (opts->new_branch_log)
 		die(_("'%s' cannot be used with updating paths"), "-l");
 
-	if (opts->force && opts->patch_mode)
-		die(_("'%s' cannot be used with updating paths"), "-f");
+	if (opts->ignore_unmerged && opts->patch_mode)
+		die(_("'%s' cannot be used with updating paths"),
+		    opts->ignore_unmerged_opt);
 
 	if (opts->force_detach)
 		die(_("'%s' cannot be used with updating paths"), "--detach");
@@ -342,16 +421,46 @@ static int checkout_paths(const struct checkout_opts *opts,
 	if (opts->merge && opts->patch_mode)
 		die(_("'%s' cannot be used with %s"), "--merge", "--patch");
 
-	if (opts->force && opts->merge)
-		die(_("'%s' cannot be used with %s"), "-f", "-m");
+	if (opts->ignore_unmerged && opts->merge)
+		die(_("'%s' cannot be used with %s"),
+		    opts->ignore_unmerged_opt, "-m");
 
 	if (opts->new_branch)
 		die(_("Cannot update paths and switch to branch '%s' at the same time."),
 		    opts->new_branch);
 
-	if (opts->patch_mode)
-		return run_add_interactive(revision, "--patch=checkout",
-					   &opts->pathspec);
+	if (!opts->checkout_worktree && !opts->checkout_index)
+		die(_("neither '%s' or '%s' is specified"),
+		    "--staged", "--worktree");
+
+	if (!opts->checkout_worktree && !opts->from_treeish)
+		die(_("'%s' must be used when '%s' is not specified"),
+		    "--worktree", "--source");
+
+	if (opts->checkout_index && !opts->checkout_worktree &&
+	    opts->writeout_stage)
+		die(_("'%s' or '%s' cannot be used with %s"),
+		    "--ours", "--theirs", "--staged");
+
+	if (opts->checkout_index && !opts->checkout_worktree &&
+	    opts->merge)
+		die(_("'%s' or '%s' cannot be used with %s"),
+		    "--merge", "--conflict", "--staged");
+
+	if (opts->patch_mode) {
+		const char *patch_mode;
+
+		if (opts->checkout_index && opts->checkout_worktree)
+			patch_mode = "--patch=checkout";
+		else if (opts->checkout_index && !opts->checkout_worktree)
+			patch_mode = "--patch=reset";
+		else if (!opts->checkout_index && opts->checkout_worktree)
+			patch_mode = "--patch=worktree";
+		else
+			BUG("either flag must have been set, worktree=%d, index=%d",
+			    opts->checkout_worktree, opts->checkout_index);
+		return run_add_interactive(revision, patch_mode, &opts->pathspec);
+	}
 
 	repo_hold_locked_index(the_repository, &lock_file, LOCK_DIE_ON_ERROR);
 	if (read_cache_preload(&opts->pathspec) < 0)
@@ -392,8 +501,9 @@ static int checkout_paths(const struct checkout_opts *opts,
 		if (ce->ce_flags & CE_MATCHED) {
 			if (!ce_stage(ce))
 				continue;
-			if (opts->force) {
-				warning(_("path '%s' is unmerged"), ce->name);
+			if (opts->ignore_unmerged) {
+				if (!opts->quiet)
+					warning(_("path '%s' is unmerged"), ce->name);
 			} else if (opts->writeout_stage) {
 				errs |= check_stage(opts->writeout_stage, ce, pos, opts->overlay_mode);
 			} else if (opts->merge) {
@@ -409,57 +519,31 @@ static int checkout_paths(const struct checkout_opts *opts,
 		return 1;
 
 	/* Now we are committed to check them out */
-	state.force = 1;
-	state.refresh_cache = 1;
-	state.istate = &the_index;
+	if (opts->checkout_worktree)
+		errs |= checkout_worktree(opts);
 
-	enable_delayed_checkout(&state);
-	for (pos = 0; pos < active_nr; pos++) {
-		struct cache_entry *ce = active_cache[pos];
-		if (ce->ce_flags & CE_MATCHED) {
-			if (!ce_stage(ce)) {
-				errs |= checkout_entry(ce, &state,
-						       NULL, &nr_checkouts);
-				continue;
-			}
-			if (opts->writeout_stage)
-				errs |= checkout_stage(opts->writeout_stage,
-						       ce, pos,
-						       &state,
-						       &nr_checkouts, opts->overlay_mode);
-			else if (opts->merge)
-				errs |= checkout_merged(pos, &state,
-							&nr_unmerged);
-			pos = skip_same_name(ce, pos) - 1;
-		}
-	}
-	remove_marked_cache_entries(&the_index, 1);
-	remove_scheduled_dirs();
-	errs |= finish_delayed_checkout(&state, &nr_checkouts);
+	/*
+	 * Allow updating the index when checking out from the index.
+	 * This is to save new stat info.
+	 */
+	if (opts->checkout_worktree && !opts->checkout_index && !opts->source_tree)
+		checkout_index = 1;
+	else
+		checkout_index = opts->checkout_index;
 
-	if (opts->count_checkout_paths) {
-		if (nr_unmerged)
-			fprintf_ln(stderr, Q_("Recreated %d merge conflict",
-					      "Recreated %d merge conflicts",
-					      nr_unmerged),
-				   nr_unmerged);
-		if (opts->source_tree)
-			fprintf_ln(stderr, Q_("Updated %d path from %s",
-					      "Updated %d paths from %s",
-					      nr_checkouts),
-				   nr_checkouts,
-				   find_unique_abbrev(&opts->source_tree->object.oid,
-						      DEFAULT_ABBREV));
-		else if (!nr_unmerged || nr_checkouts)
-			fprintf_ln(stderr, Q_("Updated %d path from the index",
-					      "Updated %d paths from the index",
-					      nr_checkouts),
-				   nr_checkouts);
+	if (checkout_index) {
+		if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
+			die(_("unable to write new index file"));
+	} else {
+		/*
+		 * NEEDSWORK: if --worktree is not specified, we
+		 * should save stat info of checked out files in the
+		 * index to avoid the next (potentially costly)
+		 * refresh. But it's a bit tricker to do...
+		 */
+		rollback_lock_file(&lock_file);
 	}
 
-	if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
-		die(_("unable to write new index file"));
-
 	read_ref_full("HEAD", 0, &rev, NULL);
 	head = lookup_commit_reference_gently(the_repository, &rev, 1);
 
@@ -553,112 +637,6 @@ static void setup_branch_path(struct branch_info *branch)
 	branch->path = strbuf_detach(&buf, NULL);
 }
 
-/*
- * Skip merging the trees, updating the index and working directory if and
- * only if we are creating a new branch via "git checkout -b <new_branch>."
- */
-static int skip_merge_working_tree(const struct checkout_opts *opts,
-	const struct branch_info *old_branch_info,
-	const struct branch_info *new_branch_info)
-{
-	/*
-	 * Do the merge if sparse checkout is on and the user has not opted in
-	 * to the optimized behavior
-	 */
-	if (core_apply_sparse_checkout && !checkout_optimize_new_branch)
-		return 0;
-
-	/*
-	 * We must do the merge if we are actually moving to a new commit.
-	 */
-	if (!old_branch_info->commit || !new_branch_info->commit ||
-		!oideq(&old_branch_info->commit->object.oid,
-		       &new_branch_info->commit->object.oid))
-		return 0;
-
-	/*
-	 * opts->patch_mode cannot be used with switching branches so is
-	 * not tested here
-	 */
-
-	/*
-	 * opts->quiet only impacts output so doesn't require a merge
-	 */
-
-	/*
-	 * Honor the explicit request for a three-way merge or to throw away
-	 * local changes
-	 */
-	if (opts->merge || opts->force)
-		return 0;
-
-	/*
-	 * --detach is documented as "updating the index and the files in the
-	 * working tree" but this optimization skips those steps so fall through
-	 * to the regular code path.
-	 */
-	if (opts->force_detach)
-		return 0;
-
-	/*
-	 * opts->writeout_stage cannot be used with switching branches so is
-	 * not tested here
-	 */
-
-	/*
-	 * Honor the explicit ignore requests
-	 */
-	if (!opts->overwrite_ignore || opts->ignore_skipworktree ||
-		opts->ignore_other_worktrees)
-		return 0;
-
-	/*
-	 * opts->show_progress only impacts output so doesn't require a merge
-	 */
-
-	/*
-	 * opts->overlay_mode cannot be used with switching branches so is
-	 * not tested here
-	 */
-
-	/*
-	 * If we aren't creating a new branch any changes or updates will
-	 * happen in the existing branch.  Since that could only be updating
-	 * the index and working directory, we don't want to skip those steps
-	 * or we've defeated any purpose in running the command.
-	 */
-	if (!opts->new_branch)
-		return 0;
-
-	/*
-	 * new_branch_force is defined to "create/reset and checkout a branch"
-	 * so needs to go through the merge to do the reset
-	 */
-	if (opts->new_branch_force)
-		return 0;
-
-	/*
-	 * A new orphaned branch requrires the index and the working tree to be
-	 * adjusted to <start_point>
-	 */
-	if (opts->new_orphan_branch)
-		return 0;
-
-	/*
-	 * Remaining variables are not checkout options but used to track state
-	 */
-
-	 /*
-	  * Do the merge if this is the initial checkout. We cannot use
-	  * is_cache_unborn() here because the index hasn't been loaded yet
-	  * so cache_nr and timestamp.sec are always zero.
-	  */
-	if (!file_exists(get_index_file()))
-		return 0;
-
-	return 1;
-}
-
 static int merge_working_tree(const struct checkout_opts *opts,
 			      struct branch_info *old_branch_info,
 			      struct branch_info *new_branch_info,
@@ -666,15 +644,21 @@ static int merge_working_tree(const struct checkout_opts *opts,
 {
 	int ret;
 	struct lock_file lock_file = LOCK_INIT;
+	struct tree *new_tree;
 
 	hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
 	if (read_cache_preload(NULL) < 0)
 		return error(_("index file corrupt"));
 
 	resolve_undo_clear();
-	if (opts->force) {
-		ret = reset_tree(get_commit_tree(new_branch_info->commit),
-				 opts, 1, writeout_error);
+	if (opts->new_orphan_branch && opts->orphan_from_empty_tree) {
+		if (new_branch_info->commit)
+			BUG("'switch --orphan' should never accept a commit as starting point");
+		new_tree = parse_tree_indirect(the_hash_algo->empty_tree);
+	} else
+		new_tree = get_commit_tree(new_branch_info->commit);
+	if (opts->discard_changes) {
+		ret = reset_tree(new_tree, opts, 1, writeout_error);
 		if (ret)
 			return ret;
 	} else {
@@ -712,7 +696,8 @@ static int merge_working_tree(const struct checkout_opts *opts,
 					   &old_branch_info->commit->object.oid :
 					   the_hash_algo->empty_tree);
 		init_tree_desc(&trees[0], tree->buffer, tree->size);
-		tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
+		parse_tree(new_tree);
+		tree = new_tree;
 		init_tree_desc(&trees[1], tree->buffer, tree->size);
 
 		ret = unpack_trees(2, trees, &topts);
@@ -777,7 +762,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
 			o.verbosity = 0;
 			work = write_tree_from_memory(&o);
 
-			ret = reset_tree(get_commit_tree(new_branch_info->commit),
+			ret = reset_tree(new_tree,
 					 opts, 1,
 					 writeout_error);
 			if (ret)
@@ -786,13 +771,13 @@ static int merge_working_tree(const struct checkout_opts *opts,
 			o.branch1 = new_branch_info->name;
 			o.branch2 = "local";
 			ret = merge_trees(&o,
-					  get_commit_tree(new_branch_info->commit),
+					  new_tree,
 					  work,
 					  old_tree,
 					  &result);
 			if (ret < 0)
 				exit(128);
-			ret = reset_tree(get_commit_tree(new_branch_info->commit),
+			ret = reset_tree(new_tree,
 					 opts, 0,
 					 writeout_error);
 			strbuf_release(&o.obuf);
@@ -810,7 +795,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
 	if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
 		die(_("unable to write new index file"));
 
-	if (!opts->force && !opts->quiet)
+	if (!opts->discard_changes && !opts->quiet && new_branch_info->commit)
 		show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
 
 	return 0;
@@ -915,7 +900,7 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 				delete_reflog(old_branch_info->path);
 		}
 	}
-	remove_branch_state(the_repository);
+	remove_branch_state(the_repository, !opts->quiet);
 	strbuf_release(&msg);
 	if (!opts->quiet &&
 	    (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD"))))
@@ -1011,7 +996,10 @@ static void orphaned_commit_warning(struct commit *old_commit, struct commit *ne
 	add_pending_object(&revs, object, oid_to_hex(&object->oid));
 
 	for_each_ref(add_pending_uninteresting_ref, &revs);
-	add_pending_oid(&revs, "HEAD", &new_commit->object.oid, UNINTERESTING);
+	if (new_commit)
+		add_pending_oid(&revs, "HEAD",
+				&new_commit->object.oid,
+				UNINTERESTING);
 
 	if (prepare_revision_walk(&revs))
 		die(_("internal error in revision walk"));
@@ -1032,6 +1020,7 @@ static int switch_branches(const struct checkout_opts *opts,
 	void *path_to_free;
 	struct object_id rev;
 	int flag, writeout_error = 0;
+	int do_merge = 1;
 
 	trace2_cmd_mode("branch");
 
@@ -1045,22 +1034,26 @@ static int switch_branches(const struct checkout_opts *opts,
 	if (old_branch_info.path)
 		skip_prefix(old_branch_info.path, "refs/heads/", &old_branch_info.name);
 
+	if (opts->new_orphan_branch && opts->orphan_from_empty_tree) {
+		if (new_branch_info->name)
+			BUG("'switch --orphan' should never accept a commit as starting point");
+		new_branch_info->commit = NULL;
+		new_branch_info->name = "(empty)";
+		do_merge = 1;
+	}
+
 	if (!new_branch_info->name) {
 		new_branch_info->name = "HEAD";
 		new_branch_info->commit = old_branch_info.commit;
 		if (!new_branch_info->commit)
 			die(_("You are on a branch yet to be born"));
 		parse_commit_or_die(new_branch_info->commit);
+
+		if (opts->only_merge_on_switching_branches)
+			do_merge = 0;
 	}
 
-	/* optimize the "checkout -b <new_branch> path */
-	if (skip_merge_working_tree(opts, &old_branch_info, new_branch_info)) {
-		if (!checkout_optimize_new_branch && !opts->quiet) {
-			if (read_cache_preload(NULL) < 0)
-				return error(_("index file corrupt"));
-			show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
-		}
-	} else {
+	if (do_merge) {
 		ret = merge_working_tree(opts, &old_branch_info, new_branch_info, &writeout_error);
 		if (ret) {
 			free(path_to_free);
@@ -1080,11 +1073,6 @@ static int switch_branches(const struct checkout_opts *opts,
 
 static int git_checkout_config(const char *var, const char *value, void *cb)
 {
-	if (!strcmp(var, "checkout.optimizenewbranch")) {
-		checkout_optimize_new_branch = git_config_bool(var, value);
-		return 0;
-	}
-
 	if (!strcmp(var, "diff.ignoresubmodules")) {
 		struct checkout_opts *opts = cb;
 		handle_ignore_submodules_arg(&opts->diff_options, value);
@@ -1097,6 +1085,34 @@ static int git_checkout_config(const char *var, const char *value, void *cb)
 	return git_xmerge_config(var, value, NULL);
 }
 
+static void setup_new_branch_info_and_source_tree(
+	struct branch_info *new_branch_info,
+	struct checkout_opts *opts,
+	struct object_id *rev,
+	const char *arg)
+{
+	struct tree **source_tree = &opts->source_tree;
+	struct object_id branch_rev;
+
+	new_branch_info->name = arg;
+	setup_branch_path(new_branch_info);
+
+	if (!check_refname_format(new_branch_info->path, 0) &&
+	    !read_ref(new_branch_info->path, &branch_rev))
+		oidcpy(rev, &branch_rev);
+	else
+		new_branch_info->path = NULL; /* not an existing branch */
+
+	new_branch_info->commit = lookup_commit_reference_gently(the_repository, rev, 1);
+	if (!new_branch_info->commit) {
+		/* not a commit */
+		*source_tree = parse_tree_indirect(rev);
+	} else {
+		parse_commit_or_die(new_branch_info->commit);
+		*source_tree = get_commit_tree(new_branch_info->commit);
+	}
+}
+
 static int parse_branchname_arg(int argc, const char **argv,
 				int dwim_new_local_branch_ok,
 				struct branch_info *new_branch_info,
@@ -1104,10 +1120,8 @@ static int parse_branchname_arg(int argc, const char **argv,
 				struct object_id *rev,
 				int *dwim_remotes_matched)
 {
-	struct tree **source_tree = &opts->source_tree;
 	const char **new_branch = &opts->new_branch;
 	int argcount = 0;
-	struct object_id branch_rev;
 	const char *arg;
 	int dash_dash_pos;
 	int has_dash_dash = 0;
@@ -1157,10 +1171,16 @@ static int parse_branchname_arg(int argc, const char **argv,
 	if (!argc)
 		return 0;
 
+	if (!opts->accept_pathspec) {
+		if (argc > 1)
+			die(_("only one reference expected"));
+		has_dash_dash = 1; /* helps disambiguate */
+	}
+
 	arg = argv[0];
 	dash_dash_pos = -1;
 	for (i = 0; i < argc; i++) {
-		if (!strcmp(argv[i], "--")) {
+		if (opts->accept_pathspec && !strcmp(argv[i], "--")) {
 			dash_dash_pos = i;
 			break;
 		}
@@ -1194,11 +1214,12 @@ static int parse_branchname_arg(int argc, const char **argv,
 			recover_with_dwim = 0;
 
 		/*
-		 * Accept "git checkout foo" and "git checkout foo --"
-		 * as candidates for dwim.
+		 * Accept "git checkout foo", "git checkout foo --"
+		 * and "git switch foo" as candidates for dwim.
 		 */
 		if (!(argc == 1 && !has_dash_dash) &&
-		    !(argc == 2 && has_dash_dash))
+		    !(argc == 2 && has_dash_dash) &&
+		    opts->accept_pathspec)
 			recover_with_dwim = 0;
 
 		if (recover_with_dwim) {
@@ -1229,26 +1250,11 @@ static int parse_branchname_arg(int argc, const char **argv,
 	argv++;
 	argc--;
 
-	new_branch_info->name = arg;
-	setup_branch_path(new_branch_info);
-
-	if (!check_refname_format(new_branch_info->path, 0) &&
-	    !read_ref(new_branch_info->path, &branch_rev))
-		oidcpy(rev, &branch_rev);
-	else
-		new_branch_info->path = NULL; /* not an existing branch */
-
-	new_branch_info->commit = lookup_commit_reference_gently(the_repository, rev, 1);
-	if (!new_branch_info->commit) {
-		/* not a commit */
-		*source_tree = parse_tree_indirect(rev);
-	} else {
-		parse_commit_or_die(new_branch_info->commit);
-		*source_tree = get_commit_tree(new_branch_info->commit);
-	}
+	setup_new_branch_info_and_source_tree(new_branch_info, opts, rev, arg);
 
-	if (!*source_tree)                   /* case (1): want a tree */
+	if (!opts->source_tree)                   /* case (1): want a tree */
 		die(_("reference is not a tree: %s"), arg);
+
 	if (!has_dash_dash) {	/* case (3).(d) -> (1) */
 		/*
 		 * Do not complain the most common case
@@ -1258,7 +1264,7 @@ static int parse_branchname_arg(int argc, const char **argv,
 		 */
 		if (argc)
 			verify_non_filename(opts->prefix, arg);
-	} else {
+	} else if (opts->accept_pathspec) {
 		argcount++;
 		argv++;
 		argc--;
@@ -1285,6 +1291,60 @@ static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
 	return status;
 }
 
+static void die_expecting_a_branch(const struct branch_info *branch_info)
+{
+	struct object_id oid;
+	char *to_free;
+
+	if (dwim_ref(branch_info->name, strlen(branch_info->name), &oid, &to_free) == 1) {
+		const char *ref = to_free;
+
+		if (skip_prefix(ref, "refs/tags/", &ref))
+			die(_("a branch is expected, got tag '%s'"), ref);
+		if (skip_prefix(ref, "refs/remotes/", &ref))
+			die(_("a branch is expected, got remote branch '%s'"), ref);
+		die(_("a branch is expected, got '%s'"), ref);
+	}
+	if (branch_info->commit)
+		die(_("a branch is expected, got commit '%s'"), branch_info->name);
+	/*
+	 * This case should never happen because we already die() on
+	 * non-commit, but just in case.
+	 */
+	die(_("a branch is expected, got '%s'"), branch_info->name);
+}
+
+static void die_if_some_operation_in_progress(void)
+{
+	struct wt_status_state state;
+
+	memset(&state, 0, sizeof(state));
+	wt_status_get_state(the_repository, &state, 0);
+
+	if (state.merge_in_progress)
+		die(_("cannot switch branch while merging\n"
+		      "Consider \"git merge --quit\" "
+		      "or \"git worktree add\"."));
+	if (state.am_in_progress)
+		die(_("cannot switch branch in the middle of an am session\n"
+		      "Consider \"git am --quit\" "
+		      "or \"git worktree add\"."));
+	if (state.rebase_interactive_in_progress || state.rebase_in_progress)
+		die(_("cannot switch branch while rebasing\n"
+		      "Consider \"git rebase --quit\" "
+		      "or \"git worktree add\"."));
+	if (state.cherry_pick_in_progress)
+		die(_("cannot switch branch while cherry-picking\n"
+		      "Consider \"git cherry-pick --quit\" "
+		      "or \"git worktree add\"."));
+	if (state.revert_in_progress)
+		die(_("cannot switch branch while reverting\n"
+		      "Consider \"git revert --quit\" "
+		      "or \"git worktree add\"."));
+	if (state.bisect_in_progress)
+		warning(_("you are switching branch while bisecting"));
+}
+
 static int checkout_branch(struct checkout_opts *opts,
 			   struct branch_info *new_branch_info)
 {
@@ -1295,9 +1355,9 @@ static int checkout_branch(struct checkout_opts *opts,
 		die(_("'%s' cannot be used with switching branches"),
 		    "--patch");
 
-	if (!opts->overlay_mode)
+	if (opts->overlay_mode != -1)
 		die(_("'%s' cannot be used with switching branches"),
-		    "--no-overlay");
+		    "--[no]-overlay");
 
 	if (opts->writeout_stage)
 		die(_("'%s' cannot be used with switching branches"),
@@ -1306,6 +1366,9 @@ static int checkout_branch(struct checkout_opts *opts,
 	if (opts->force && opts->merge)
 		die(_("'%s' cannot be used with '%s'"), "-f", "-m");
 
+	if (opts->discard_changes && opts->merge)
+		die(_("'%s' cannot be used with '%s'"), "--discard-changes", "--merge");
+
 	if (opts->force_detach && opts->new_branch)
 		die(_("'%s' cannot be used with '%s'"),
 		    "--detach", "-b/-B/--orphan");
@@ -1313,6 +1376,8 @@ static int checkout_branch(struct checkout_opts *opts,
 	if (opts->new_orphan_branch) {
 		if (opts->track != BRANCH_TRACK_UNSPECIFIED)
 			die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
+		if (opts->orphan_from_empty_tree && new_branch_info->name)
+			die(_("'%s' cannot take <start-point>"), "--orphan");
 	} else if (opts->force_detach) {
 		if (opts->track != BRANCH_TRACK_UNSPECIFIED)
 			die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
@@ -1323,6 +1388,23 @@ static int checkout_branch(struct checkout_opts *opts,
 		die(_("Cannot switch branch to a non-commit '%s'"),
 		    new_branch_info->name);
 
+	if (!opts->switch_branch_doing_nothing_is_ok &&
+	    !new_branch_info->name &&
+	    !opts->new_branch &&
+	    !opts->force_detach)
+		die(_("missing branch or commit argument"));
+
+	if (!opts->implicit_detach &&
+	    !opts->force_detach &&
+	    !opts->new_branch &&
+	    !opts->new_branch_force &&
+	    new_branch_info->name &&
+	    !new_branch_info->path)
+		die_expecting_a_branch(new_branch_info);
+
+	if (!opts->can_switch_when_in_progress)
+		die_if_some_operation_in_progress();
+
 	if (new_branch_info->path && !opts->force_detach && !opts->new_branch &&
 	    !opts->ignore_other_worktrees) {
 		int flag;
@@ -1344,99 +1426,148 @@ static int checkout_branch(struct checkout_opts *opts,
 	return switch_branches(opts, new_branch_info);
 }
 
-int cmd_checkout(int argc, const char **argv, const char *prefix)
+static struct option *add_common_options(struct checkout_opts *opts,
+					 struct option *prevopts)
 {
-	struct checkout_opts opts;
-	struct branch_info new_branch_info;
-	char *conflict_style = NULL;
-	int dwim_new_local_branch, no_dwim_new_local_branch = 0;
-	int dwim_remotes_matched = 0;
 	struct option options[] = {
-		OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
-		OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
-			   N_("create and checkout a new branch")),
-		OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
-			   N_("create/reset and checkout a branch")),
-		OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
-		OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
-		OPT_SET_INT('t', "track",  &opts.track, N_("set upstream info for new branch"),
+		OPT__QUIET(&opts->quiet, N_("suppress progress reporting")),
+		{ OPTION_CALLBACK, 0, "recurse-submodules", NULL,
+			    "checkout", "control recursive updating of submodules",
+			    PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
+		OPT_BOOL(0, "progress", &opts->show_progress, N_("force progress reporting")),
+		OPT_BOOL('m', "merge", &opts->merge, N_("perform a 3-way merge with the new branch")),
+		OPT_STRING(0, "conflict", &opts->conflict_style, N_("style"),
+			   N_("conflict style (merge or diff3)")),
+		OPT_END()
+	};
+	struct option *newopts = parse_options_concat(prevopts, options);
+	free(prevopts);
+	return newopts;
+}
+
+static struct option *add_common_switch_branch_options(
+	struct checkout_opts *opts, struct option *prevopts)
+{
+	struct option options[] = {
+		OPT_BOOL('d', "detach", &opts->force_detach, N_("detach HEAD at named commit")),
+		OPT_SET_INT('t', "track",  &opts->track, N_("set upstream info for new branch"),
 			BRANCH_TRACK_EXPLICIT),
-		OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
-		OPT_SET_INT_F('2', "ours", &opts.writeout_stage,
+		OPT__FORCE(&opts->force, N_("force checkout (throw away local modifications)"),
+			   PARSE_OPT_NOCOMPLETE),
+		OPT_STRING(0, "orphan", &opts->new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
+		OPT_BOOL_F(0, "overwrite-ignore", &opts->overwrite_ignore,
+			   N_("update ignored files (default)"),
+			   PARSE_OPT_NOCOMPLETE),
+		OPT_BOOL(0, "ignore-other-worktrees", &opts->ignore_other_worktrees,
+			 N_("do not check if another worktree is holding the given ref")),
+		OPT_END()
+	};
+	struct option *newopts = parse_options_concat(prevopts, options);
+	free(prevopts);
+	return newopts;
+}
+
+static struct option *add_checkout_path_options(struct checkout_opts *opts,
+						struct option *prevopts)
+{
+	struct option options[] = {
+		OPT_SET_INT_F('2', "ours", &opts->writeout_stage,
 			      N_("checkout our version for unmerged files"),
 			      2, PARSE_OPT_NONEG),
-		OPT_SET_INT_F('3', "theirs", &opts.writeout_stage,
+		OPT_SET_INT_F('3', "theirs", &opts->writeout_stage,
 			      N_("checkout their version for unmerged files"),
 			      3, PARSE_OPT_NONEG),
-		OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)"),
-			   PARSE_OPT_NOCOMPLETE),
-		OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
-		OPT_BOOL_F(0, "overwrite-ignore", &opts.overwrite_ignore,
-			   N_("update ignored files (default)"),
-			   PARSE_OPT_NOCOMPLETE),
-		OPT_STRING(0, "conflict", &conflict_style, N_("style"),
-			   N_("conflict style (merge or diff3)")),
-		OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
-		OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
+		OPT_BOOL('p', "patch", &opts->patch_mode, N_("select hunks interactively")),
+		OPT_BOOL(0, "ignore-skip-worktree-bits", &opts->ignore_skipworktree,
 			 N_("do not limit pathspecs to sparse entries only")),
-		OPT_BOOL(0, "no-guess", &no_dwim_new_local_branch,
-			 N_("do not second guess 'git checkout <no-such-branch>'")),
-		OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
-			 N_("do not check if another worktree is holding the given ref")),
-		{ OPTION_CALLBACK, 0, "recurse-submodules", NULL,
-			    "checkout", "control recursive updating of submodules",
-			    PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
-		OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
-		OPT_BOOL(0, "overlay", &opts.overlay_mode, N_("use overlay mode (default)")),
-		OPT_END(),
+		OPT_END()
 	};
+	struct option *newopts = parse_options_concat(prevopts, options);
+	free(prevopts);
+	return newopts;
+}
+
+static int checkout_main(int argc, const char **argv, const char *prefix,
+			 struct checkout_opts *opts, struct option *options,
+			 const char * const usagestr[])
+{
+	struct branch_info new_branch_info;
+	int dwim_remotes_matched = 0;
+	int parseopt_flags = 0;
 
-	memset(&opts, 0, sizeof(opts));
 	memset(&new_branch_info, 0, sizeof(new_branch_info));
-	opts.overwrite_ignore = 1;
-	opts.prefix = prefix;
-	opts.show_progress = -1;
-	opts.overlay_mode = -1;
+	opts->overwrite_ignore = 1;
+	opts->prefix = prefix;
+	opts->show_progress = -1;
+
+	git_config(git_checkout_config, opts);
 
-	git_config(git_checkout_config, &opts);
+	opts->track = BRANCH_TRACK_UNSPECIFIED;
 
-	opts.track = BRANCH_TRACK_UNSPECIFIED;
+	if (!opts->accept_pathspec && !opts->accept_ref)
+		BUG("make up your mind, you need to take _something_");
+	if (opts->accept_pathspec && opts->accept_ref)
+		parseopt_flags = PARSE_OPT_KEEP_DASHDASH;
 
-	argc = parse_options(argc, argv, prefix, options, checkout_usage,
-			     PARSE_OPT_KEEP_DASHDASH);
+	argc = parse_options(argc, argv, prefix, options,
+			     usagestr, parseopt_flags);
 
-	dwim_new_local_branch = !no_dwim_new_local_branch;
-	if (opts.show_progress < 0) {
-		if (opts.quiet)
-			opts.show_progress = 0;
+	if (opts->show_progress < 0) {
+		if (opts->quiet)
+			opts->show_progress = 0;
 		else
-			opts.show_progress = isatty(2);
+			opts->show_progress = isatty(2);
 	}
 
-	if (conflict_style) {
-		opts.merge = 1; /* implied */
-		git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
+	if (opts->conflict_style) {
+		opts->merge = 1; /* implied */
+		git_xmerge_config("merge.conflictstyle", opts->conflict_style, NULL);
+	}
+	if (opts->force) {
+		opts->discard_changes = 1;
+		opts->ignore_unmerged_opt = "--force";
+		opts->ignore_unmerged = 1;
 	}
 
-	if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
+	if ((!!opts->new_branch + !!opts->new_branch_force + !!opts->new_orphan_branch) > 1)
 		die(_("-b, -B and --orphan are mutually exclusive"));
 
-	if (opts.overlay_mode == 1 && opts.patch_mode)
+	if (opts->overlay_mode == 1 && opts->patch_mode)
 		die(_("-p and --overlay are mutually exclusive"));
 
+	if (opts->checkout_index >= 0 || opts->checkout_worktree >= 0) {
+		if (opts->checkout_index < 0)
+			opts->checkout_index = 0;
+		if (opts->checkout_worktree < 0)
+			opts->checkout_worktree = 0;
+	} else {
+		if (opts->checkout_index < 0)
+			opts->checkout_index = -opts->checkout_index - 1;
+		if (opts->checkout_worktree < 0)
+			opts->checkout_worktree = -opts->checkout_worktree - 1;
+	}
+	if (opts->checkout_index < 0 || opts->checkout_worktree < 0)
+		BUG("these flags should be non-negative by now");
+	/*
+	 * convenient shortcut: "git restore --staged" equals
+	 * "git restore --staged --source HEAD"
+	 */
+	if (!opts->from_treeish && opts->checkout_index && !opts->checkout_worktree)
+		opts->from_treeish = "HEAD";
+
 	/*
 	 * From here on, new_branch will contain the branch to be checked out,
 	 * and new_branch_force and new_orphan_branch will tell us which one of
 	 * -b/-B/--orphan is being used.
 	 */
-	if (opts.new_branch_force)
-		opts.new_branch = opts.new_branch_force;
+	if (opts->new_branch_force)
+		opts->new_branch = opts->new_branch_force;
 
-	if (opts.new_orphan_branch)
-		opts.new_branch = opts.new_orphan_branch;
+	if (opts->new_orphan_branch)
+		opts->new_branch = opts->new_orphan_branch;
 
 	/* --track without -b/-B/--orphan should DWIM */
-	if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
+	if (opts->track != BRANCH_TRACK_UNSPECIFIED && !opts->new_branch) {
 		const char *argv0 = argv[0];
 		if (!argc || !strcmp(argv0, "--"))
 			die(_("--track needs a branch name"));
@@ -1445,7 +1576,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 		argv0 = strchr(argv0, '/');
 		if (!argv0 || !argv0[1])
 			die(_("missing branch name; try -b"));
-		opts.new_branch = argv0 + 1;
+		opts->new_branch = argv0 + 1;
 	}
 
 	/*
@@ -1461,59 +1592,75 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 	 * including "last branch" syntax and DWIM-ery for names of
 	 * remote branches, erroring out for invalid or ambiguous cases.
 	 */
-	if (argc) {
+	if (argc && opts->accept_ref) {
 		struct object_id rev;
 		int dwim_ok =
-			!opts.patch_mode &&
-			dwim_new_local_branch &&
-			opts.track == BRANCH_TRACK_UNSPECIFIED &&
-			!opts.new_branch;
+			!opts->patch_mode &&
+			opts->dwim_new_local_branch &&
+			opts->track == BRANCH_TRACK_UNSPECIFIED &&
+			!opts->new_branch;
 		int n = parse_branchname_arg(argc, argv, dwim_ok,
-					     &new_branch_info, &opts, &rev,
+					     &new_branch_info, opts, &rev,
 					     &dwim_remotes_matched);
 		argv += n;
 		argc -= n;
+	} else if (!opts->accept_ref && opts->from_treeish) {
+		struct object_id rev;
+
+		if (get_oid_mb(opts->from_treeish, &rev))
+			die(_("could not resolve %s"), opts->from_treeish);
+
+		setup_new_branch_info_and_source_tree(&new_branch_info,
+						      opts, &rev,
+						      opts->from_treeish);
+
+		if (!opts->source_tree)
+			die(_("reference is not a tree: %s"), opts->from_treeish);
 	}
 
+	if (opts->accept_pathspec && !opts->empty_pathspec_ok && !argc &&
+	    !opts->patch_mode)	/* patch mode is special */
+		die(_("you must specify path(s) to restore"));
+
 	if (argc) {
-		parse_pathspec(&opts.pathspec, 0,
-			       opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
+		parse_pathspec(&opts->pathspec, 0,
+			       opts->patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
 			       prefix, argv);
 
-		if (!opts.pathspec.nr)
+		if (!opts->pathspec.nr)
 			die(_("invalid path specification"));
 
 		/*
 		 * Try to give more helpful suggestion.
 		 * new_branch && argc > 1 will be caught later.
 		 */
-		if (opts.new_branch && argc == 1)
+		if (opts->new_branch && argc == 1)
 			die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
-				argv[0], opts.new_branch);
+				argv[0], opts->new_branch);
 
-		if (opts.force_detach)
+		if (opts->force_detach)
 			die(_("git checkout: --detach does not take a path argument '%s'"),
 			    argv[0]);
 
-		if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
+		if (1 < !!opts->writeout_stage + !!opts->force + !!opts->merge)
 			die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
 			      "checking out of the index."));
 	}
 
-	if (opts.new_branch) {
+	if (opts->new_branch) {
 		struct strbuf buf = STRBUF_INIT;
 
-		if (opts.new_branch_force)
-			opts.branch_exists = validate_branchname(opts.new_branch, &buf);
+		if (opts->new_branch_force)
+			opts->branch_exists = validate_branchname(opts->new_branch, &buf);
 		else
-			opts.branch_exists =
-				validate_new_branchname(opts.new_branch, &buf, 0);
+			opts->branch_exists =
+				validate_new_branchname(opts->new_branch, &buf, 0);
 		strbuf_release(&buf);
 	}
 
 	UNLEAK(opts);
-	if (opts.patch_mode || opts.pathspec.nr) {
-		int ret = checkout_paths(&opts, new_branch_info.name);
+	if (opts->patch_mode || opts->pathspec.nr) {
+		int ret = checkout_paths(opts, new_branch_info.name);
 		if (ret && dwim_remotes_matched > 1 &&
 		    advice_checkout_ambiguous_remote_branch_name)
 			advise(_("'%s' matched more than one remote tracking branch.\n"
@@ -1532,6 +1679,123 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 			       dwim_remotes_matched);
 		return ret;
 	} else {
-		return checkout_branch(&opts, &new_branch_info);
+		return checkout_branch(opts, &new_branch_info);
 	}
 }
+
+int cmd_checkout(int argc, const char **argv, const char *prefix)
+{
+	struct checkout_opts opts;
+	struct option *options;
+	struct option checkout_options[] = {
+		OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
+			   N_("create and checkout a new branch")),
+		OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
+			   N_("create/reset and checkout a branch")),
+		OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
+		OPT_BOOL(0, "guess", &opts.dwim_new_local_branch,
+			 N_("second guess 'git checkout <no-such-branch>' (default)")),
+		OPT_BOOL(0, "overlay", &opts.overlay_mode, N_("use overlay mode (default)")),
+		OPT_END()
+	};
+	int ret;
+
+	memset(&opts, 0, sizeof(opts));
+	opts.dwim_new_local_branch = 1;
+	opts.switch_branch_doing_nothing_is_ok = 1;
+	opts.only_merge_on_switching_branches = 0;
+	opts.accept_ref = 1;
+	opts.accept_pathspec = 1;
+	opts.implicit_detach = 1;
+	opts.can_switch_when_in_progress = 1;
+	opts.orphan_from_empty_tree = 0;
+	opts.empty_pathspec_ok = 1;
+	opts.overlay_mode = -1;
+	opts.checkout_index = -2;    /* default on */
+	opts.checkout_worktree = -2; /* default on */
+
+	options = parse_options_dup(checkout_options);
+	options = add_common_options(&opts, options);
+	options = add_common_switch_branch_options(&opts, options);
+	options = add_checkout_path_options(&opts, options);
+
+	ret = checkout_main(argc, argv, prefix, &opts,
+			    options, checkout_usage);
+	FREE_AND_NULL(options);
+	return ret;
+}
+
+int cmd_switch(int argc, const char **argv, const char *prefix)
+{
+	struct checkout_opts opts;
+	struct option *options = NULL;
+	struct option switch_options[] = {
+		OPT_STRING('c', "create", &opts.new_branch, N_("branch"),
+			   N_("create and switch to a new branch")),
+		OPT_STRING('C', "force-create", &opts.new_branch_force, N_("branch"),
+			   N_("create/reset and switch to a branch")),
+		OPT_BOOL(0, "guess", &opts.dwim_new_local_branch,
+			 N_("second guess 'git switch <no-such-branch>'")),
+		OPT_BOOL(0, "discard-changes", &opts.discard_changes,
+			 N_("throw away local modifications")),
+		OPT_END()
+	};
+	int ret;
+
+	memset(&opts, 0, sizeof(opts));
+	opts.dwim_new_local_branch = 1;
+	opts.accept_ref = 1;
+	opts.accept_pathspec = 0;
+	opts.switch_branch_doing_nothing_is_ok = 0;
+	opts.only_merge_on_switching_branches = 1;
+	opts.implicit_detach = 0;
+	opts.can_switch_when_in_progress = 0;
+	opts.orphan_from_empty_tree = 1;
+	opts.overlay_mode = -1;
+
+	options = parse_options_dup(switch_options);
+	options = add_common_options(&opts, options);
+	options = add_common_switch_branch_options(&opts, options);
+
+	ret = checkout_main(argc, argv, prefix, &opts,
+			    options, switch_branch_usage);
+	FREE_AND_NULL(options);
+	return ret;
+}
+
+int cmd_restore(int argc, const char **argv, const char *prefix)
+{
+	struct checkout_opts opts;
+	struct option *options;
+	struct option restore_options[] = {
+		OPT_STRING('s', "source", &opts.from_treeish, "<tree-ish>",
+			   N_("where the checkout from")),
+		OPT_BOOL('S', "staged", &opts.checkout_index,
+			   N_("restore the index")),
+		OPT_BOOL('W', "worktree", &opts.checkout_worktree,
+			   N_("restore the working tree (default)")),
+		OPT_BOOL(0, "ignore-unmerged", &opts.ignore_unmerged,
+			 N_("ignore unmerged entries")),
+		OPT_BOOL(0, "overlay", &opts.overlay_mode, N_("use overlay mode")),
+		OPT_END()
+	};
+	int ret;
+
+	memset(&opts, 0, sizeof(opts));
+	opts.accept_ref = 0;
+	opts.accept_pathspec = 1;
+	opts.empty_pathspec_ok = 0;
+	opts.overlay_mode = 0;
+	opts.checkout_index = -1;    /* default off */
+	opts.checkout_worktree = -2; /* default on */
+	opts.ignore_unmerged_opt = "--ignore-unmerged";
+
+	options = parse_options_dup(restore_options);
+	options = add_common_options(&opts, options);
+	options = add_checkout_path_options(&opts, options);
+
+	ret = checkout_main(argc, argv, prefix, &opts,
+			    options, restore_usage);
+	FREE_AND_NULL(options);
+	return ret;
+}
diff --git a/builtin/clone.c b/builtin/clone.c
index 5b9ebe9947..a4fe72879d 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -494,7 +494,7 @@ static enum {
 static const char junk_leave_repo_msg[] =
 N_("Clone succeeded, but checkout failed.\n"
    "You can inspect what was checked out with 'git status'\n"
-   "and retry the checkout with 'git checkout -f HEAD'\n");
+   "and retry with 'git restore --source=HEAD :/'\n");
 
 static void remove_junk(void)
 {
@@ -1252,7 +1252,7 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	transport_disconnect(transport);
 
 	if (option_dissociate) {
-		close_all_packs(the_repository->objects);
+		close_object_store(the_repository->objects);
 		dissociate_from_references();
 	}
 
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 537fdfd0f0..d8efa5bab2 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -141,6 +141,8 @@ static int graph_write(int argc, const char **argv)
 	struct string_list *pack_indexes = NULL;
 	struct string_list *commit_hex = NULL;
 	struct string_list lines;
+	int result = 0;
+	unsigned int flags = COMMIT_GRAPH_PROGRESS;
 
 	static struct option builtin_commit_graph_write_options[] = {
 		OPT_STRING(0, "object-dir", &opts.obj_dir,
@@ -165,13 +167,13 @@ static int graph_write(int argc, const char **argv)
 		die(_("use at most one of --reachable, --stdin-commits, or --stdin-packs"));
 	if (!opts.obj_dir)
 		opts.obj_dir = get_object_directory();
+	if (opts.append)
+		flags |= COMMIT_GRAPH_APPEND;
 
 	read_replace_refs = 0;
 
-	if (opts.reachable) {
-		write_commit_graph_reachable(opts.obj_dir, opts.append, 1);
-		return 0;
-	}
+	if (opts.reachable)
+		return write_commit_graph_reachable(opts.obj_dir, flags);
 
 	string_list_init(&lines, 0);
 	if (opts.stdin_packs || opts.stdin_commits) {
@@ -188,14 +190,14 @@ static int graph_write(int argc, const char **argv)
 		UNLEAK(buf);
 	}
 
-	write_commit_graph(opts.obj_dir,
-			   pack_indexes,
-			   commit_hex,
-			   opts.append,
-			   1);
+	if (write_commit_graph(opts.obj_dir,
+			       pack_indexes,
+			       commit_hex,
+			       flags))
+		result = 1;
 
 	UNLEAK(lines);
-	return 0;
+	return result;
 }
 
 int cmd_commit_graph(int argc, const char **argv, const char *prefix)
diff --git a/builtin/commit.c b/builtin/commit.c
index 1c9e8e2228..3b561c2a75 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1078,9 +1078,11 @@ static const char *read_commit_message(const char *name)
 static struct status_deferred_config {
 	enum wt_status_format status_format;
 	int show_branch;
+	enum ahead_behind_flags ahead_behind;
 } status_deferred_config = {
 	STATUS_FORMAT_UNSPECIFIED,
-	-1 /* unspecified */
+	-1, /* unspecified */
+	AHEAD_BEHIND_UNSPECIFIED,
 };
 
 static void finalize_deferred_config(struct wt_status *s)
@@ -1107,6 +1109,17 @@ static void finalize_deferred_config(struct wt_status *s)
 	if (s->show_branch < 0)
 		s->show_branch = 0;
 
+	/*
+	 * If the user did not give a "--[no]-ahead-behind" command
+	 * line argument *AND* we will print in a human-readable format
+	 * (short, long etc.) then we inherit from the status.aheadbehind
+	 * config setting.  In all other cases (and porcelain V[12] formats
+	 * in particular), we inherit _FULL for backwards compatibility.
+	 */
+	if (use_deferred_config &&
+	    s->ahead_behind_flags == AHEAD_BEHIND_UNSPECIFIED)
+		s->ahead_behind_flags = status_deferred_config.ahead_behind;
+
 	if (s->ahead_behind_flags == AHEAD_BEHIND_UNSPECIFIED)
 		s->ahead_behind_flags = AHEAD_BEHIND_FULL;
 }
@@ -1246,6 +1259,10 @@ static int git_status_config(const char *k, const char *v, void *cb)
 		status_deferred_config.show_branch = git_config_bool(k, v);
 		return 0;
 	}
+	if (!strcmp(k, "status.aheadbehind")) {
+		status_deferred_config.ahead_behind = git_config_bool(k, v);
+		return 0;
+	}
 	if (!strcmp(k, "status.showstash")) {
 		s->show_stash = git_config_bool(k, v);
 		return 0;
@@ -1658,7 +1675,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		die("%s", err.buf);
 	}
 
-	sequencer_post_commit_cleanup(the_repository);
+	sequencer_post_commit_cleanup(the_repository, 0);
 	unlink(git_path_merge_head(the_repository));
 	unlink(git_path_merge_msg(the_repository));
 	unlink(git_path_merge_mode(the_repository));
@@ -1667,10 +1684,11 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 	if (commit_index_files())
 		die(_("repository has been updated, but unable to write\n"
 		      "new_index file. Check that disk is not full and quota is\n"
-		      "not exceeded, and then \"git reset HEAD\" to recover."));
+		      "not exceeded, and then \"git restore --staged :/\" to recover."));
 
-	if (git_env_bool(GIT_TEST_COMMIT_GRAPH, 0))
-		write_commit_graph_reachable(get_object_directory(), 0, 0);
+	if (git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
+	    write_commit_graph_reachable(get_object_directory(), 0))
+		return 1;
 
 	repo_rerere(the_repository, 0);
 	run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
diff --git a/builtin/describe.c b/builtin/describe.c
index 1409cedce2..200154297d 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -76,7 +76,7 @@ static int commit_name_neq(const void *unused_cmp_data,
 
 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
 {
-	return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
+	return hashmap_get_from_hash(&names, oidhash(peeled), peeled);
 }
 
 static int replace_name(struct commit_name *e,
@@ -123,7 +123,7 @@ static void add_to_known_names(const char *path,
 		if (!e) {
 			e = xmalloc(sizeof(struct commit_name));
 			oidcpy(&e->peeled, peeled);
-			hashmap_entry_init(e, sha1hash(peeled->hash));
+			hashmap_entry_init(e, oidhash(peeled));
 			hashmap_add(&names, e);
 			e->path = NULL;
 		}
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index c22cef3b2f..f541f55d33 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -275,7 +275,7 @@ static void export_blob(const struct object_id *oid)
 	if (is_null_oid(oid))
 		return;
 
-	object = lookup_object(the_repository, oid->hash);
+	object = lookup_object(the_repository, oid);
 	if (object && object->flags & SHOWN)
 		return;
 
@@ -453,7 +453,7 @@ static void show_filemodify(struct diff_queue_struct *q,
 						  &spec->oid));
 			else {
 				struct object *object = lookup_object(the_repository,
-								      spec->oid.hash);
+								      &spec->oid);
 				printf("M %06o :%d ", spec->mode,
 				       get_object_mark(object));
 			}
diff --git a/builtin/fetch.c b/builtin/fetch.c
index cf7eb0dd8d..53ce99d2bb 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -52,6 +52,7 @@ static int prune_tags = -1; /* unspecified */
 
 static int all, append, dry_run, force, keep, multiple, update_head_ok, verbosity, deepen_relative;
 static int progress = -1;
+static int enable_auto_gc = 1;
 static int tags = TAGS_DEFAULT, unshallow, update_shallow, deepen;
 static int max_children = 1;
 static enum transport_family family;
@@ -178,6 +179,8 @@ static struct option builtin_fetch_options[] = {
 	OPT_STRING_LIST(0, "negotiation-tip", &negotiation_tip, N_("revision"),
 			N_("report that we have only objects reachable from this object")),
 	OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
+	OPT_BOOL(0, "auto-gc", &enable_auto_gc,
+		 N_("run 'gc --auto' after fetching")),
 	OPT_BOOL(0, "show-forced-updates", &fetch_show_forced_updates,
 		 N_("check for forced-updates on all updated branches")),
 	OPT_END()
@@ -250,6 +253,7 @@ static int will_fetch(struct ref **head, const unsigned char *sha1)
 struct refname_hash_entry {
 	struct hashmap_entry ent; /* must be the first member */
 	struct object_id oid;
+	int ignore;
 	char refname[FLEX_ARRAY];
 };
 
@@ -298,6 +302,11 @@ static int refname_hash_exists(struct hashmap *map, const char *refname)
 	return !!hashmap_get_from_hash(map, strhash(refname), refname);
 }
 
+static void clear_item(struct refname_hash_entry *item)
+{
+	item->ignore = 1;
+}
+
 static void find_non_local_tags(const struct ref *refs,
 				struct ref **head,
 				struct ref ***tail)
@@ -330,7 +339,7 @@ static void find_non_local_tags(const struct ref *refs,
 			    !will_fetch(head, ref->old_oid.hash) &&
 			    !has_object_file_with_flags(&item->oid, OBJECT_INFO_QUICK) &&
 			    !will_fetch(head, item->oid.hash))
-				oidclr(&item->oid);
+				clear_item(item);
 			item = NULL;
 			continue;
 		}
@@ -344,7 +353,7 @@ static void find_non_local_tags(const struct ref *refs,
 		if (item &&
 		    !has_object_file_with_flags(&item->oid, OBJECT_INFO_QUICK) &&
 		    !will_fetch(head, item->oid.hash))
-			oidclr(&item->oid);
+			clear_item(item);
 
 		item = NULL;
 
@@ -365,7 +374,7 @@ static void find_non_local_tags(const struct ref *refs,
 	if (item &&
 	    !has_object_file_with_flags(&item->oid, OBJECT_INFO_QUICK) &&
 	    !will_fetch(head, item->oid.hash))
-		oidclr(&item->oid);
+		clear_item(item);
 
 	/*
 	 * For all the tags in the remote_refs_list,
@@ -373,19 +382,21 @@ static void find_non_local_tags(const struct ref *refs,
 	 */
 	for_each_string_list_item(remote_ref_item, &remote_refs_list) {
 		const char *refname = remote_ref_item->string;
+		struct ref *rm;
 
 		item = hashmap_get_from_hash(&remote_refs, strhash(refname), refname);
 		if (!item)
 			BUG("unseen remote ref?");
 
 		/* Unless we have already decided to ignore this item... */
-		if (!is_null_oid(&item->oid)) {
-			struct ref *rm = alloc_ref(item->refname);
-			rm->peer_ref = alloc_ref(item->refname);
-			oidcpy(&rm->old_oid, &item->oid);
-			**tail = rm;
-			*tail = &rm->next;
-		}
+		if (item->ignore)
+			continue;
+
+		rm = alloc_ref(item->refname);
+		rm->peer_ref = alloc_ref(item->refname);
+		oidcpy(&rm->old_oid, &item->oid);
+		**tail = rm;
+		*tail = &rm->next;
 	}
 	hashmap_free(&remote_refs, 1);
 	string_list_clear(&remote_refs_list, 0);
@@ -1456,7 +1467,7 @@ static int fetch_multiple(struct string_list *list)
 			return errcode;
 	}
 
-	argv_array_pushl(&argv, "fetch", "--append", NULL);
+	argv_array_pushl(&argv, "fetch", "--append", "--no-auto-gc", NULL);
 	add_options_to_argv(&argv);
 
 	for (i = 0; i < list->nr; i++) {
@@ -1704,13 +1715,15 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 
 	string_list_clear(&list, 0);
 
-	close_all_packs(the_repository->objects);
+	close_object_store(the_repository->objects);
 
-	argv_array_pushl(&argv_gc_auto, "gc", "--auto", NULL);
-	if (verbosity < 0)
-		argv_array_push(&argv_gc_auto, "--quiet");
-	run_command_v_opt(argv_gc_auto.argv, RUN_GIT_CMD);
-	argv_array_clear(&argv_gc_auto);
+	if (enable_auto_gc) {
+		argv_array_pushl(&argv_gc_auto, "gc", "--auto", NULL);
+		if (verbosity < 0)
+			argv_array_push(&argv_gc_auto, "--quiet");
+		run_command_v_opt(argv_gc_auto.argv, RUN_GIT_CMD);
+		argv_array_clear(&argv_gc_auto);
+	}
 
 	return result;
 }
diff --git a/builtin/fsck.c b/builtin/fsck.c
index d26fb0a044..18403a94fa 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -238,7 +238,7 @@ static int mark_used(struct object *obj, int type, void *data, struct fsck_optio
 static void mark_unreachable_referents(const struct object_id *oid)
 {
 	struct fsck_options options = FSCK_OPTIONS_DEFAULT;
-	struct object *obj = lookup_object(the_repository, oid->hash);
+	struct object *obj = lookup_object(the_repository, oid);
 
 	if (!obj || !(obj->flags & HAS_OBJ))
 		return; /* not part of our original set */
@@ -497,7 +497,7 @@ static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
 	struct object *obj;
 
 	if (!is_null_oid(oid)) {
-		obj = lookup_object(the_repository, oid->hash);
+		obj = lookup_object(the_repository, oid);
 		if (obj && (obj->flags & HAS_OBJ)) {
 			if (timestamp && name_objects)
 				add_decoration(fsck_walk_options.object_names,
@@ -756,7 +756,7 @@ static int fsck_cache_tree(struct cache_tree *it)
 
 static void mark_object_for_connectivity(const struct object_id *oid)
 {
-	struct object *obj = lookup_unknown_object(oid->hash);
+	struct object *obj = lookup_unknown_object(oid);
 	obj->flags |= HAS_OBJ;
 }
 
@@ -879,7 +879,7 @@ int cmd_fsck(int argc, const char **argv, const char *prefix)
 		struct object_id oid;
 		if (!get_oid(arg, &oid)) {
 			struct object *obj = lookup_object(the_repository,
-							   oid.hash);
+							   &oid);
 
 			if (!obj || !(obj->flags & HAS_OBJ)) {
 				if (is_promisor_object(&oid))
diff --git a/builtin/gc.c b/builtin/gc.c
index 8943bcc300..be8e0bfcbe 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -653,7 +653,7 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 	gc_before_repack();
 
 	if (!repository_format_precious_objects) {
-		close_all_packs(the_repository->objects);
+		close_object_store(the_repository->objects);
 		if (run_command_v_opt(repack.argv, RUN_GIT_CMD))
 			die(FAILED_RUN, repack.argv[0]);
 
@@ -681,13 +681,14 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 	report_garbage = report_pack_garbage;
 	reprepare_packed_git(the_repository);
 	if (pack_garbage.nr > 0) {
-		close_all_packs(the_repository->objects);
+		close_object_store(the_repository->objects);
 		clean_pack_garbage();
 	}
 
-	if (gc_write_commit_graph)
-		write_commit_graph_reachable(get_object_directory(), 0,
-					     !quiet && !daemonized);
+	if (gc_write_commit_graph &&
+	    write_commit_graph_reachable(get_object_directory(),
+					 !quiet && !daemonized ? COMMIT_GRAPH_PROGRESS : 0))
+		return 1;
 
 	if (auto_gc && too_many_loose_objects())
 		warning(_("There are too many unreachable loose objects; "
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index ccf4eb7e9b..0d55f73b0b 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -14,6 +14,7 @@
 #include "thread-utils.h"
 #include "packfile.h"
 #include "object-store.h"
+#include "fetch-object.h"
 
 static const char index_pack_usage[] =
 "git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
@@ -1351,6 +1352,25 @@ static void fix_unresolved_deltas(struct hashfile *f)
 		sorted_by_pos[i] = &ref_deltas[i];
 	QSORT(sorted_by_pos, nr_ref_deltas, delta_pos_compare);
 
+	if (repository_format_partial_clone) {
+		/*
+		 * Prefetch the delta bases.
+		 */
+		struct oid_array to_fetch = OID_ARRAY_INIT;
+		for (i = 0; i < nr_ref_deltas; i++) {
+			struct ref_delta_entry *d = sorted_by_pos[i];
+			if (!oid_object_info_extended(the_repository, &d->oid,
+						      NULL,
+						      OBJECT_INFO_FOR_PREFETCH))
+				continue;
+			oid_array_append(&to_fetch, &d->oid);
+		}
+		if (to_fetch.nr)
+			fetch_objects(repository_format_partial_clone,
+				      to_fetch.oid, to_fetch.nr);
+		oid_array_clear(&to_fetch);
+	}
+
 	for (i = 0; i < nr_ref_deltas; i++) {
 		struct ref_delta_entry *d = sorted_by_pos[i];
 		enum object_type type;
@@ -1650,8 +1670,10 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	int report_end_of_input = 0;
 
 	/*
-	 * index-pack never needs to fetch missing objects, since it only
-	 * accesses the repo to do hash collision checks
+	 * index-pack never needs to fetch missing objects except when
+	 * REF_DELTA bases are missing (which are explicitly handled). It only
+	 * accesses the repo to do hash collision checks and to check which
+	 * REF_DELTA bases need to be fetched.
 	 */
 	fetch_if_missing = 0;
 
diff --git a/builtin/interpret-trailers.c b/builtin/interpret-trailers.c
index 8ae40dec47..f101d092b8 100644
--- a/builtin/interpret-trailers.c
+++ b/builtin/interpret-trailers.c
@@ -10,6 +10,7 @@
 #include "parse-options.h"
 #include "string-list.h"
 #include "trailer.h"
+#include "config.h"
 
 static const char * const git_interpret_trailers_usage[] = {
 	N_("git interpret-trailers [--in-place] [--trim-empty] [(--trailer <token>[(=|:)<value>])...] [<file>...]"),
@@ -112,6 +113,8 @@ int cmd_interpret_trailers(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 
+	git_config(git_default_config, NULL);
+
 	argc = parse_options(argc, argv, prefix, options,
 			     git_interpret_trailers_usage, 0);
 
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index 7f83c9a6f2..670e8fb93c 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -373,7 +373,7 @@ static void prune_index(struct index_state *istate,
 	first = pos;
 	last = istate->cache_nr;
 	while (last > first) {
-		int next = (last + first) >> 1;
+		int next = first + ((last - first) >> 1);
 		const struct cache_entry *ce = istate->cache[next];
 		if (!strncmp(ce->name, prefix, prefixlen)) {
 			first = next+1;
diff --git a/builtin/merge.c b/builtin/merge.c
index 6e99aead46..aad5a9504c 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -453,7 +453,7 @@ static void finish(struct commit *head_commit,
 			 * We ignore errors in 'gc --auto', since the
 			 * user should see them.
 			 */
-			close_all_packs(the_repository->objects);
+			close_object_store(the_repository->objects);
 			run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 		}
 	}
diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index 16df43473a..c785fe16ba 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -378,8 +378,7 @@ static void name_rev_line(char *p, struct name_ref_data *data)
 			*(p+1) = 0;
 			if (!get_oid(p - (hexsz - 1), &oid)) {
 				struct object *o =
-					lookup_object(the_repository,
-						      oid.hash);
+					lookup_object(the_repository, &oid);
 				if (o)
 					name = get_rev_name(o, &buf);
 			}
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index b2be8869c2..000dc4b872 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -606,12 +606,12 @@ static int mark_tagged(const char *path, const struct object_id *oid, int flag,
 		       void *cb_data)
 {
 	struct object_id peeled;
-	struct object_entry *entry = packlist_find(&to_pack, oid->hash, NULL);
+	struct object_entry *entry = packlist_find(&to_pack, oid, NULL);
 
 	if (entry)
 		entry->tagged = 1;
 	if (!peel_ref(path, &peeled)) {
-		entry = packlist_find(&to_pack, peeled.hash, NULL);
+		entry = packlist_find(&to_pack, &peeled, NULL);
 		if (entry)
 			entry->tagged = 1;
 	}
@@ -996,7 +996,7 @@ static int have_duplicate_entry(const struct object_id *oid,
 {
 	struct object_entry *entry;
 
-	entry = packlist_find(&to_pack, oid->hash, index_pos);
+	entry = packlist_find(&to_pack, oid, index_pos);
 	if (!entry)
 		return 0;
 
@@ -1494,11 +1494,13 @@ static int can_reuse_delta(const unsigned char *base_sha1,
 	if (!base_sha1)
 		return 0;
 
+	oidread(&base_oid, base_sha1);
+
 	/*
 	 * First see if we're already sending the base (or it's explicitly in
 	 * our "excluded" list).
 	 */
-	base = packlist_find(&to_pack, base_sha1, NULL);
+	base = packlist_find(&to_pack, &base_oid, NULL);
 	if (base) {
 		if (!in_same_island(&delta->idx.oid, &base->idx.oid))
 			return 0;
@@ -1511,7 +1513,6 @@ static int can_reuse_delta(const unsigned char *base_sha1,
 	 * even if it was buried too deep in history to make it into the
 	 * packing list.
 	 */
-	oidread(&base_oid, base_sha1);
 	if (thin && bitmap_has_oid_in_uninteresting(bitmap_git, &base_oid)) {
 		if (use_delta_islands) {
 			if (!in_same_island(&delta->idx.oid, &base_oid))
@@ -2571,7 +2572,7 @@ static void add_tag_chain(const struct object_id *oid)
 	 * it was included via bitmaps, we would not have parsed it
 	 * previously).
 	 */
-	if (packlist_find(&to_pack, oid->hash, NULL))
+	if (packlist_find(&to_pack, oid, NULL))
 		return;
 
 	tag = lookup_tag(the_repository, oid);
@@ -2595,7 +2596,7 @@ static int add_ref_tag(const char *path, const struct object_id *oid, int flag,
 
 	if (starts_with(path, "refs/tags/") && /* is a tag? */
 	    !peel_ref(path, &peeled)    && /* peelable? */
-	    packlist_find(&to_pack, peeled.hash, NULL))      /* object packed? */
+	    packlist_find(&to_pack, &peeled, NULL))      /* object packed? */
 		add_tag_chain(oid);
 	return 0;
 }
@@ -2795,7 +2796,7 @@ static void show_object(struct object *obj, const char *name, void *data)
 		for (p = strchr(name, '/'); p; p = strchr(p + 1, '/'))
 			depth++;
 
-		ent = packlist_find(&to_pack, obj->oid.hash, NULL);
+		ent = packlist_find(&to_pack, &obj->oid, NULL);
 		if (ent && depth > oe_tree_depth(&to_pack, ent))
 			oe_set_tree_depth(&to_pack, ent, depth);
 	}
@@ -2922,7 +2923,7 @@ static void add_objects_in_unpacked_packs(void)
 
 		for (i = 0; i < p->num_objects; i++) {
 			nth_packed_object_oid(&oid, p, i);
-			o = lookup_unknown_object(oid.hash);
+			o = lookup_unknown_object(&oid);
 			if (!(o->flags & OBJECT_ADDED))
 				mark_in_pack_object(o, p, &in_pack);
 			o->flags |= OBJECT_ADDED;
@@ -3026,7 +3027,7 @@ static void loosen_unused_packed_objects(void)
 
 		for (i = 0; i < p->num_objects; i++) {
 			nth_packed_object_oid(&oid, p, i);
-			if (!packlist_find(&to_pack, oid.hash, NULL) &&
+			if (!packlist_find(&to_pack, &oid, NULL) &&
 			    !has_sha1_pack_kept_or_nonlocal(&oid) &&
 			    !loosened_object_can_be_discarded(&oid, p->mtime))
 				if (force_object_loose(&oid, p->mtime))
@@ -3134,7 +3135,7 @@ static void get_object_list(int ac, const char **av)
 		return;
 
 	if (use_delta_islands)
-		load_delta_islands(the_repository);
+		load_delta_islands(the_repository, progress);
 
 	if (prepare_revision_walk(&revs))
 		die(_("revision walk setup failed"));
diff --git a/builtin/prune.c b/builtin/prune.c
index 97613eccb5..2b76872ad2 100644
--- a/builtin/prune.c
+++ b/builtin/prune.c
@@ -53,7 +53,7 @@ static int is_object_reachable(const struct object_id *oid,
 
 	perform_reachability_traversal(revs);
 
-	obj = lookup_object(the_repository, oid->hash);
+	obj = lookup_object(the_repository, oid);
 	return obj && (obj->flags & SEEN);
 }
 
diff --git a/builtin/rebase.c b/builtin/rebase.c
index b8116db487..3c7d8b894a 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -738,20 +738,30 @@ static int finish_rebase(struct rebase_options *opts)
 {
 	struct strbuf dir = STRBUF_INIT;
 	const char *argv_gc_auto[] = { "gc", "--auto", NULL };
+	int ret = 0;
 
 	delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 	apply_autostash(opts);
-	close_all_packs(the_repository->objects);
+	close_object_store(the_repository->objects);
 	/*
 	 * We ignore errors in 'gc --auto', since the
 	 * user should see them.
 	 */
 	run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
-	strbuf_addstr(&dir, opts->state_dir);
-	remove_dir_recursively(&dir, 0);
-	strbuf_release(&dir);
+	if (opts->type == REBASE_INTERACTIVE) {
+		struct replay_opts replay = REPLAY_OPTS_INIT;
 
-	return 0;
+		replay.action = REPLAY_INTERACTIVE_REBASE;
+		ret = sequencer_remove_state(&replay);
+	} else {
+		strbuf_addstr(&dir, opts->state_dir);
+		if (remove_dir_recursively(&dir, 0))
+			ret = error(_("could not remove '%s'"),
+				    opts->state_dir);
+		strbuf_release(&dir);
+	}
+
+	return ret;
 }
 
 static struct commit *peel_committish(const char *name)
@@ -1600,7 +1610,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 		if (reset_head(NULL, "reset", NULL, RESET_HEAD_HARD,
 			       NULL, NULL) < 0)
 			die(_("could not discard worktree changes"));
-		remove_branch_state(the_repository);
+		remove_branch_state(the_repository, 0);
 		if (read_basic_state(&options))
 			exit(1);
 		goto run_rebase;
@@ -1620,16 +1630,24 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 			       NULL, NULL) < 0)
 			die(_("could not move back to %s"),
 			    oid_to_hex(&options.orig_head));
-		remove_branch_state(the_repository);
-		ret = finish_rebase(&options);
+		remove_branch_state(the_repository, 0);
+		ret = !!finish_rebase(&options);
 		goto cleanup;
 	}
 	case ACTION_QUIT: {
-		strbuf_reset(&buf);
-		strbuf_addstr(&buf, options.state_dir);
-		ret = !!remove_dir_recursively(&buf, 0);
-		if (ret)
-			die(_("could not remove '%s'"), options.state_dir);
+		if (options.type == REBASE_INTERACTIVE) {
+			struct replay_opts replay = REPLAY_OPTS_INIT;
+
+			replay.action = REPLAY_INTERACTIVE_REBASE;
+			ret = !!sequencer_remove_state(&replay);
+		} else {
+			strbuf_reset(&buf);
+			strbuf_addstr(&buf, options.state_dir);
+			ret = !!remove_dir_recursively(&buf, 0);
+			if (ret)
+				error(_("could not remove '%s'"),
+				       options.state_dir);
+		}
 		goto cleanup;
 	}
 	case ACTION_EDIT_TODO:
@@ -2141,6 +2159,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 	ret = !!run_specific_rebase(&options, action);
 
 cleanup:
+	strbuf_release(&buf);
 	strbuf_release(&revisions);
 	free(options.head_name);
 	free(options.gpg_sign_opt);
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 77b7122456..610eadf5f0 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -2042,7 +2042,7 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 			proc.git_cmd = 1;
 			proc.argv = argv_gc_auto;
 
-			close_all_packs(the_repository->objects);
+			close_object_store(the_repository->objects);
 			if (!start_command(&proc)) {
 				if (use_sideband)
 					copy_to_sideband(proc.err, -1, NULL);
diff --git a/builtin/repack.c b/builtin/repack.c
index caca113927..f834b5551b 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -422,7 +422,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 	if (!names.nr && !po_args.quiet)
 		printf_ln(_("Nothing new to pack."));
 
-	close_all_packs(the_repository->objects);
+	close_object_store(the_repository->objects);
 
 	/*
 	 * Ok we have prepared all new packfiles.
diff --git a/builtin/reset.c b/builtin/reset.c
index 26ef9a7bd0..c2bb35a4b7 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -421,7 +421,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 			print_new_head_line(lookup_commit_reference(the_repository, &oid));
 	}
 	if (!pathspec.nr)
-		remove_branch_state(the_repository);
+		remove_branch_state(the_repository, 0);
 
 	return update_ref_status;
 }
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index 660172b014..301ccb970b 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -49,6 +49,7 @@ static const char rev_list_usage[] =
 "    --objects | --objects-edge\n"
 "    --unpacked\n"
 "    --header | --pretty\n"
+"    --[no-]object-names\n"
 "    --abbrev=<n> | --no-abbrev\n"
 "    --abbrev-commit\n"
 "    --left-right\n"
@@ -75,6 +76,9 @@ enum missing_action {
 };
 static enum missing_action arg_missing_action;
 
+/* display only the oid of each object encountered */
+static int arg_show_object_names = 1;
+
 #define DEFAULT_OIDSET_SIZE     (16*1024)
 
 static void finish_commit(struct commit *commit);
@@ -255,7 +259,10 @@ static void show_object(struct object *obj, const char *name, void *cb_data)
 	display_progress(progress, ++progress_counter);
 	if (info->flags & REV_LIST_QUIET)
 		return;
-	show_object_with_name(stdout, obj, name);
+	if (arg_show_object_names)
+		show_object_with_name(stdout, obj, name);
+	else
+		printf("%s\n", oid_to_hex(&obj->oid));
 }
 
 static void show_edge(struct commit *commit)
@@ -484,6 +491,16 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 		if (skip_prefix(arg, "--missing=", &arg))
 			continue; /* already handled above */
 
+		if (!strcmp(arg, ("--no-object-names"))) {
+			arg_show_object_names = 0;
+			continue;
+		}
+
+		if (!strcmp(arg, ("--object-names"))) {
+			arg_show_object_names = 1;
+			continue;
+		}
+
 		usage(rev_list_usage);
 
 	}
diff --git a/builtin/revert.c b/builtin/revert.c
index d4dcedbdc6..4e71b2f2aa 100644
--- a/builtin/revert.c
+++ b/builtin/revert.c
@@ -203,7 +203,7 @@ static int run_sequencer(int argc, const char **argv, struct replay_opts *opts)
 	if (cmd == 'q') {
 		int ret = sequencer_remove_state(opts);
 		if (!ret)
-			remove_branch_state(the_repository);
+			remove_branch_state(the_repository, 0);
 		return ret;
 	}
 	if (cmd == 'c')
diff --git a/builtin/stash.c b/builtin/stash.c
index 2a8e6d09b4..fde6397caa 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -713,11 +713,11 @@ static int git_stash_config(const char *var, const char *value, void *cb)
 static int show_stash(int argc, const char **argv, const char *prefix)
 {
 	int i;
-	int opts = 0;
 	int ret = 0;
 	struct stash_info info;
 	struct rev_info rev;
 	struct argv_array stash_args = ARGV_ARRAY_INIT;
+	struct argv_array revision_args = ARGV_ARRAY_INIT;
 	struct option options[] = {
 		OPT_END()
 	};
@@ -726,11 +726,12 @@ static int show_stash(int argc, const char **argv, const char *prefix)
 	git_config(git_diff_ui_config, NULL);
 	init_revisions(&rev, prefix);
 
+	argv_array_push(&revision_args, argv[0]);
 	for (i = 1; i < argc; i++) {
 		if (argv[i][0] != '-')
 			argv_array_push(&stash_args, argv[i]);
 		else
-			opts++;
+			argv_array_push(&revision_args, argv[i]);
 	}
 
 	ret = get_stash_info(&info, stash_args.argc, stash_args.argv);
@@ -742,7 +743,7 @@ static int show_stash(int argc, const char **argv, const char *prefix)
 	 * The config settings are applied only if there are not passed
 	 * any options.
 	 */
-	if (!opts) {
+	if (revision_args.argc == 1) {
 		git_config(git_stash_config, NULL);
 		if (show_stat)
 			rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT;
@@ -756,7 +757,7 @@ static int show_stash(int argc, const char **argv, const char *prefix)
 		}
 	}
 
-	argc = setup_revisions(argc, argv, &rev, NULL);
+	argc = setup_revisions(revision_args.argc, revision_args.argv, &rev, NULL);
 	if (argc > 1) {
 		free_stash_info(&info);
 		usage_with_options(git_stash_show_usage, options);
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 13da32d3b7..909e77e802 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -540,6 +540,7 @@ static void runcommand_in_submodule_cb(const struct cache_entry *list_item,
 		if (info->quiet)
 			argv_array_push(&cpr.args, "--quiet");
 
+		argv_array_push(&cpr.args, "--");
 		argv_array_pushv(&cpr.args, info->argv);
 
 		if (run_command(&cpr))
diff --git a/builtin/tag.c b/builtin/tag.c
index ef37dccf86..e0a4c25382 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -33,6 +33,7 @@ static const char * const git_tag_usage[] = {
 
 static unsigned int colopts;
 static int force_sign_annotate;
+static int config_sign_tag = -1; /* unspecified */
 
 static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting,
 		     struct ref_format *format)
@@ -144,6 +145,11 @@ static int git_tag_config(const char *var, const char *value, void *cb)
 	int status;
 	struct ref_sorting **sorting_tail = (struct ref_sorting **)cb;
 
+	if (!strcmp(var, "tag.gpgsign")) {
+		config_sign_tag = git_config_bool(var, value);
+		return 0;
+	}
+
 	if (!strcmp(var, "tag.sort")) {
 		if (!value)
 			return config_error_nonbool(var);
@@ -442,15 +448,10 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	memset(&opt, 0, sizeof(opt));
 	memset(&filter, 0, sizeof(filter));
 	filter.lines = -1;
+	opt.sign = -1;
 
 	argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
 
-	if (keyid) {
-		opt.sign = 1;
-		set_signing_key(keyid);
-	}
-	create_tag_object = (opt.sign || annotate || msg.given || msgfile);
-
 	if (!cmdmode) {
 		if (argc == 0)
 			cmdmode = 'l';
@@ -463,6 +464,15 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	if (cmdmode == 'l')
 		setup_auto_pager("tag", 1);
 
+	if (opt.sign == -1)
+		opt.sign = cmdmode ? 0 : config_sign_tag > 0;
+
+	if (keyid) {
+		opt.sign = 1;
+		set_signing_key(keyid);
+	}
+	create_tag_object = (opt.sign || annotate || msg.given || msgfile);
+
 	if ((create_tag_object || force) && (cmdmode != 0))
 		usage_with_options(git_tag_usage, options);
 
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index 80478808b3..a87a4bfd2c 100644
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -332,7 +332,7 @@ static int resolve_against_held(unsigned nr, const struct object_id *base,
 {
 	struct object *obj;
 	struct obj_buffer *obj_buffer;
-	obj = lookup_object(the_repository, base->hash);
+	obj = lookup_object(the_repository, base);
 	if (!obj)
 		return 0;
 	obj_buffer = lookup_object_buffer(obj);
diff --git a/cache-tree.c b/cache-tree.c
index b13bfaf71e..706ffcf188 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -6,8 +6,8 @@
 #include "object-store.h"
 #include "replace-object.h"
 
-#ifndef DEBUG
-#define DEBUG 0
+#ifndef DEBUG_CACHE_TREE
+#define DEBUG_CACHE_TREE 0
 #endif
 
 struct cache_tree *cache_tree(void)
@@ -111,7 +111,7 @@ static int do_invalidate_path(struct cache_tree *it, const char *path)
 	int namelen;
 	struct cache_tree_sub *down;
 
-#if DEBUG
+#if DEBUG_CACHE_TREE
 	fprintf(stderr, "cache-tree invalidate <%s>\n", path);
 #endif
 
@@ -398,7 +398,7 @@ static int update_one(struct cache_tree *it,
 		strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
 		strbuf_add(&buffer, oid->hash, the_hash_algo->rawsz);
 
-#if DEBUG
+#if DEBUG_CACHE_TREE
 		fprintf(stderr, "cache-tree update-one %o %.*s\n",
 			mode, entlen, path + baselen);
 #endif
@@ -421,7 +421,7 @@ static int update_one(struct cache_tree *it,
 
 	strbuf_release(&buffer);
 	it->entry_count = to_invalidate ? -1 : i - *skip_count;
-#if DEBUG
+#if DEBUG_CACHE_TREE
 	fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
 		it->entry_count, it->subtree_nr,
 		oid_to_hex(&it->oid));
@@ -462,7 +462,7 @@ static void write_one(struct strbuf *buffer, struct cache_tree *it,
 	strbuf_add(buffer, path, pathlen);
 	strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
 
-#if DEBUG
+#if DEBUG_CACHE_TREE
 	if (0 <= it->entry_count)
 		fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
 			pathlen, path, it->entry_count, it->subtree_nr,
@@ -536,7 +536,7 @@ static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
 		size -= rawsz;
 	}
 
-#if DEBUG
+#if DEBUG_CACHE_TREE
 	if (0 <= it->entry_count)
 		fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
 			*buffer, it->entry_count, subtree_nr,
diff --git a/cache.h b/cache.h
index bf20337ef4..3167585cab 100644
--- a/cache.h
+++ b/cache.h
@@ -43,30 +43,6 @@ int git_deflate_end_gently(git_zstream *);
 int git_deflate(git_zstream *, int flush);
 unsigned long git_deflate_bound(git_zstream *, unsigned long);
 
-/* The length in bytes and in hex digits of an object name (SHA-1 value). */
-#define GIT_SHA1_RAWSZ 20
-#define GIT_SHA1_HEXSZ (2 * GIT_SHA1_RAWSZ)
-/* The block size of SHA-1. */
-#define GIT_SHA1_BLKSZ 64
-
-/* The length in bytes and in hex digits of an object name (SHA-256 value). */
-#define GIT_SHA256_RAWSZ 32
-#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
-/* The block size of SHA-256. */
-#define GIT_SHA256_BLKSZ 64
-
-/* The length in byte and in hex digits of the largest possible hash value. */
-#define GIT_MAX_RAWSZ GIT_SHA256_RAWSZ
-#define GIT_MAX_HEXSZ GIT_SHA256_HEXSZ
-/* The largest possible block size for any supported hash. */
-#define GIT_MAX_BLKSZ GIT_SHA256_BLKSZ
-
-struct object_id {
-	unsigned char hash[GIT_MAX_RAWSZ];
-};
-
-#define the_hash_algo the_repository->hash_algo
-
 #if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
 #define DTYPE(de)	((de)->d_type)
 #else
@@ -1759,6 +1735,7 @@ void setup_pager(void);
 int pager_in_use(void);
 extern int pager_use_color;
 int term_columns(void);
+void term_clear_line(void);
 int decimal_width(uintmax_t);
 int check_pager_config(const char *cmd);
 void prepare_pager_args(struct child_process *, const char *pager);
diff --git a/command-list.txt b/command-list.txt
index 3a9af104b5..a9ac72bef4 100644
--- a/command-list.txt
+++ b/command-list.txt
@@ -59,7 +59,7 @@ git-cat-file                            plumbinginterrogators
 git-check-attr                          purehelpers
 git-check-ignore                        purehelpers
 git-check-mailmap                       purehelpers
-git-checkout                            mainporcelain           history
+git-checkout                            mainporcelain
 git-checkout-index                      plumbingmanipulators
 git-check-ref-format                    purehelpers
 git-cherry                              plumbinginterrogators          complete
@@ -81,7 +81,7 @@ git-cvsimport                           foreignscminterface
 git-cvsserver                           foreignscminterface
 git-daemon                              synchingrepositories
 git-describe                            mainporcelain
-git-diff                                mainporcelain           history
+git-diff                                mainporcelain           info
 git-diff-files                          plumbinginterrogators
 git-diff-index                          plumbinginterrogators
 git-diff-tree                           plumbinginterrogators
@@ -150,7 +150,8 @@ git-repack                              ancillarymanipulators           complete
 git-replace                             ancillarymanipulators           complete
 git-request-pull                        foreignscminterface             complete
 git-rerere                              ancillaryinterrogators
-git-reset                               mainporcelain           worktree
+git-reset                               mainporcelain           history
+git-restore                             mainporcelain           worktree
 git-revert                              mainporcelain
 git-rev-list                            plumbinginterrogators
 git-rev-parse                           plumbinginterrogators
@@ -171,6 +172,7 @@ git-status                              mainporcelain           info
 git-stripspace                          purehelpers
 git-submodule                           mainporcelain
 git-svn                                 foreignscminterface
+git-switch                              mainporcelain           history
 git-symbolic-ref                        plumbingmanipulators
 git-tag                                 mainporcelain           history
 git-unpack-file                         plumbinginterrogators
diff --git a/commit-graph.c b/commit-graph.c
index 7c5e54875f..8cc1d1d6c3 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -361,10 +361,10 @@ int generation_numbers_enabled(struct repository *r)
 	return !!first_generation;
 }
 
-void close_commit_graph(struct repository *r)
+void close_commit_graph(struct raw_object_store *o)
 {
-	free_commit_graph(r->objects->commit_graph);
-	r->objects->commit_graph = NULL;
+	free_commit_graph(o->commit_graph);
+	o->commit_graph = NULL;
 }
 
 static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
@@ -525,14 +525,38 @@ struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit
 	return get_commit_tree_in_graph_one(r, r->objects->commit_graph, c);
 }
 
+struct packed_commit_list {
+	struct commit **list;
+	int nr;
+	int alloc;
+};
+
+struct packed_oid_list {
+	struct object_id *list;
+	int nr;
+	int alloc;
+};
+
+struct write_commit_graph_context {
+	struct repository *r;
+	const char *obj_dir;
+	char *graph_name;
+	struct packed_oid_list oids;
+	struct packed_commit_list commits;
+	int num_extra_edges;
+	unsigned long approx_nr_objects;
+	struct progress *progress;
+	int progress_done;
+	uint64_t progress_cnt;
+	unsigned append:1,
+		 report_progress:1;
+};
+
 static void write_graph_chunk_fanout(struct hashfile *f,
-				     struct commit **commits,
-				     int nr_commits,
-				     struct progress *progress,
-				     uint64_t *progress_cnt)
+				     struct write_commit_graph_context *ctx)
 {
 	int i, count = 0;
-	struct commit **list = commits;
+	struct commit **list = ctx->commits.list;
 
 	/*
 	 * Write the first-level table (the list is sorted,
@@ -540,10 +564,10 @@ static void write_graph_chunk_fanout(struct hashfile *f,
 	 * having to do eight extra binary search iterations).
 	 */
 	for (i = 0; i < 256; i++) {
-		while (count < nr_commits) {
+		while (count < ctx->commits.nr) {
 			if ((*list)->object.oid.hash[0] != i)
 				break;
-			display_progress(progress, ++*progress_cnt);
+			display_progress(ctx->progress, ++ctx->progress_cnt);
 			count++;
 			list++;
 		}
@@ -553,14 +577,12 @@ static void write_graph_chunk_fanout(struct hashfile *f,
 }
 
 static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
-				   struct commit **commits, int nr_commits,
-				   struct progress *progress,
-				   uint64_t *progress_cnt)
+				   struct write_commit_graph_context *ctx)
 {
-	struct commit **list = commits;
+	struct commit **list = ctx->commits.list;
 	int count;
-	for (count = 0; count < nr_commits; count++, list++) {
-		display_progress(progress, ++*progress_cnt);
+	for (count = 0; count < ctx->commits.nr; count++, list++) {
+		display_progress(ctx->progress, ++ctx->progress_cnt);
 		hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
 	}
 }
@@ -572,19 +594,17 @@ static const unsigned char *commit_to_sha1(size_t index, void *table)
 }
 
 static void write_graph_chunk_data(struct hashfile *f, int hash_len,
-				   struct commit **commits, int nr_commits,
-				   struct progress *progress,
-				   uint64_t *progress_cnt)
+				   struct write_commit_graph_context *ctx)
 {
-	struct commit **list = commits;
-	struct commit **last = commits + nr_commits;
+	struct commit **list = ctx->commits.list;
+	struct commit **last = ctx->commits.list + ctx->commits.nr;
 	uint32_t num_extra_edges = 0;
 
 	while (list < last) {
 		struct commit_list *parent;
 		int edge_value;
 		uint32_t packedDate[2];
-		display_progress(progress, ++*progress_cnt);
+		display_progress(ctx->progress, ++ctx->progress_cnt);
 
 		parse_commit_no_graph(*list);
 		hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
@@ -595,8 +615,8 @@ static void write_graph_chunk_data(struct hashfile *f, int hash_len,
 			edge_value = GRAPH_PARENT_NONE;
 		else {
 			edge_value = sha1_pos(parent->item->object.oid.hash,
-					      commits,
-					      nr_commits,
+					      ctx->commits.list,
+					      ctx->commits.nr,
 					      commit_to_sha1);
 
 			if (edge_value < 0)
@@ -616,8 +636,8 @@ static void write_graph_chunk_data(struct hashfile *f, int hash_len,
 			edge_value = GRAPH_EXTRA_EDGES_NEEDED | num_extra_edges;
 		else {
 			edge_value = sha1_pos(parent->item->object.oid.hash,
-					      commits,
-					      nr_commits,
+					      ctx->commits.list,
+					      ctx->commits.nr,
 					      commit_to_sha1);
 			if (edge_value < 0)
 				BUG("missing parent %s for commit %s",
@@ -649,19 +669,16 @@ static void write_graph_chunk_data(struct hashfile *f, int hash_len,
 }
 
 static void write_graph_chunk_extra_edges(struct hashfile *f,
-					  struct commit **commits,
-					  int nr_commits,
-					  struct progress *progress,
-					  uint64_t *progress_cnt)
+					  struct write_commit_graph_context *ctx)
 {
-	struct commit **list = commits;
-	struct commit **last = commits + nr_commits;
+	struct commit **list = ctx->commits.list;
+	struct commit **last = ctx->commits.list + ctx->commits.nr;
 	struct commit_list *parent;
 
 	while (list < last) {
 		int num_parents = 0;
 
-		display_progress(progress, ++*progress_cnt);
+		display_progress(ctx->progress, ++ctx->progress_cnt);
 
 		for (parent = (*list)->parents; num_parents < 3 && parent;
 		     parent = parent->next)
@@ -675,8 +692,8 @@ static void write_graph_chunk_extra_edges(struct hashfile *f,
 		/* Since num_parents > 2, this initializer is safe. */
 		for (parent = (*list)->parents->next; parent; parent = parent->next) {
 			int edge_value = sha1_pos(parent->item->object.oid.hash,
-						  commits,
-						  nr_commits,
+						  ctx->commits.list,
+						  ctx->commits.nr,
 						  commit_to_sha1);
 
 			if (edge_value < 0)
@@ -700,125 +717,111 @@ static int commit_compare(const void *_a, const void *_b)
 	return oidcmp(a, b);
 }
 
-struct packed_commit_list {
-	struct commit **list;
-	int nr;
-	int alloc;
-};
-
-struct packed_oid_list {
-	struct object_id *list;
-	int nr;
-	int alloc;
-	struct progress *progress;
-	int progress_done;
-};
-
 static int add_packed_commits(const struct object_id *oid,
 			      struct packed_git *pack,
 			      uint32_t pos,
 			      void *data)
 {
-	struct packed_oid_list *list = (struct packed_oid_list*)data;
+	struct write_commit_graph_context *ctx = (struct write_commit_graph_context*)data;
 	enum object_type type;
 	off_t offset = nth_packed_object_offset(pack, pos);
 	struct object_info oi = OBJECT_INFO_INIT;
 
-	if (list->progress)
-		display_progress(list->progress, ++list->progress_done);
+	if (ctx->progress)
+		display_progress(ctx->progress, ++ctx->progress_done);
 
 	oi.typep = &type;
-	if (packed_object_info(the_repository, pack, offset, &oi) < 0)
+	if (packed_object_info(ctx->r, pack, offset, &oi) < 0)
 		die(_("unable to get type of object %s"), oid_to_hex(oid));
 
 	if (type != OBJ_COMMIT)
 		return 0;
 
-	ALLOC_GROW(list->list, list->nr + 1, list->alloc);
-	oidcpy(&(list->list[list->nr]), oid);
-	list->nr++;
+	ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
+	oidcpy(&(ctx->oids.list[ctx->oids.nr]), oid);
+	ctx->oids.nr++;
 
 	return 0;
 }
 
-static void add_missing_parents(struct packed_oid_list *oids, struct commit *commit)
+static void add_missing_parents(struct write_commit_graph_context *ctx, struct commit *commit)
 {
 	struct commit_list *parent;
 	for (parent = commit->parents; parent; parent = parent->next) {
 		if (!(parent->item->object.flags & UNINTERESTING)) {
-			ALLOC_GROW(oids->list, oids->nr + 1, oids->alloc);
-			oidcpy(&oids->list[oids->nr], &(parent->item->object.oid));
-			oids->nr++;
+			ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
+			oidcpy(&ctx->oids.list[ctx->oids.nr], &(parent->item->object.oid));
+			ctx->oids.nr++;
 			parent->item->object.flags |= UNINTERESTING;
 		}
 	}
 }
 
-static void close_reachable(struct packed_oid_list *oids, int report_progress)
+static void close_reachable(struct write_commit_graph_context *ctx)
 {
 	int i;
 	struct commit *commit;
-	struct progress *progress = NULL;
 
-	if (report_progress)
-		progress = start_delayed_progress(
-			_("Loading known commits in commit graph"), oids->nr);
-	for (i = 0; i < oids->nr; i++) {
-		display_progress(progress, i + 1);
-		commit = lookup_commit(the_repository, &oids->list[i]);
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
+					_("Loading known commits in commit graph"),
+					ctx->oids.nr);
+	for (i = 0; i < ctx->oids.nr; i++) {
+		display_progress(ctx->progress, i + 1);
+		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
 		if (commit)
 			commit->object.flags |= UNINTERESTING;
 	}
-	stop_progress(&progress);
+	stop_progress(&ctx->progress);
 
 	/*
-	 * As this loop runs, oids->nr may grow, but not more
+	 * As this loop runs, ctx->oids.nr may grow, but not more
 	 * than the number of missing commits in the reachable
 	 * closure.
 	 */
-	if (report_progress)
-		progress = start_delayed_progress(
-			_("Expanding reachable commits in commit graph"), oids->nr);
-	for (i = 0; i < oids->nr; i++) {
-		display_progress(progress, i + 1);
-		commit = lookup_commit(the_repository, &oids->list[i]);
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
+					_("Expanding reachable commits in commit graph"),
+					ctx->oids.nr);
+	for (i = 0; i < ctx->oids.nr; i++) {
+		display_progress(ctx->progress, i + 1);
+		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
 
 		if (commit && !parse_commit_no_graph(commit))
-			add_missing_parents(oids, commit);
+			add_missing_parents(ctx, commit);
 	}
-	stop_progress(&progress);
+	stop_progress(&ctx->progress);
 
-	if (report_progress)
-		progress = start_delayed_progress(
-			_("Clearing commit marks in commit graph"), oids->nr);
-	for (i = 0; i < oids->nr; i++) {
-		display_progress(progress, i + 1);
-		commit = lookup_commit(the_repository, &oids->list[i]);
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
+					_("Clearing commit marks in commit graph"),
+					ctx->oids.nr);
+	for (i = 0; i < ctx->oids.nr; i++) {
+		display_progress(ctx->progress, i + 1);
+		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
 
 		if (commit)
 			commit->object.flags &= ~UNINTERESTING;
 	}
-	stop_progress(&progress);
+	stop_progress(&ctx->progress);
 }
 
-static void compute_generation_numbers(struct packed_commit_list* commits,
-				       int report_progress)
+static void compute_generation_numbers(struct write_commit_graph_context *ctx)
 {
 	int i;
 	struct commit_list *list = NULL;
-	struct progress *progress = NULL;
 
-	if (report_progress)
-		progress = start_progress(
-			_("Computing commit graph generation numbers"),
-			commits->nr);
-	for (i = 0; i < commits->nr; i++) {
-		display_progress(progress, i + 1);
-		if (commits->list[i]->generation != GENERATION_NUMBER_INFINITY &&
-		    commits->list[i]->generation != GENERATION_NUMBER_ZERO)
+	if (ctx->report_progress)
+		ctx->progress = start_progress(
+					_("Computing commit graph generation numbers"),
+					ctx->commits.nr);
+	for (i = 0; i < ctx->commits.nr; i++) {
+		display_progress(ctx->progress, i + 1);
+		if (ctx->commits.list[i]->generation != GENERATION_NUMBER_INFINITY &&
+		    ctx->commits.list[i]->generation != GENERATION_NUMBER_ZERO)
 			continue;
 
-		commit_list_insert(commits->list[i], &list);
+		commit_list_insert(ctx->commits.list[i], &list);
 		while (list) {
 			struct commit *current = list->item;
 			struct commit_list *parent;
@@ -845,7 +848,7 @@ static void compute_generation_numbers(struct packed_commit_list* commits,
 			}
 		}
 	}
-	stop_progress(&progress);
+	stop_progress(&ctx->progress);
 }
 
 static int add_ref_to_list(const char *refname,
@@ -858,207 +861,187 @@ static int add_ref_to_list(const char *refname,
 	return 0;
 }
 
-void write_commit_graph_reachable(const char *obj_dir, int append,
-				  int report_progress)
+int write_commit_graph_reachable(const char *obj_dir, unsigned int flags)
 {
 	struct string_list list = STRING_LIST_INIT_DUP;
+	int result;
 
 	for_each_ref(add_ref_to_list, &list);
-	write_commit_graph(obj_dir, NULL, &list, append, report_progress);
+	result = write_commit_graph(obj_dir, NULL, &list,
+				    flags);
 
 	string_list_clear(&list, 0);
+	return result;
 }
 
-void write_commit_graph(const char *obj_dir,
-			struct string_list *pack_indexes,
-			struct string_list *commit_hex,
-			int append, int report_progress)
+static int fill_oids_from_packs(struct write_commit_graph_context *ctx,
+				struct string_list *pack_indexes)
 {
-	struct packed_oid_list oids;
-	struct packed_commit_list commits;
-	struct hashfile *f;
-	uint32_t i, count_distinct = 0;
-	char *graph_name;
-	struct lock_file lk = LOCK_INIT;
-	uint32_t chunk_ids[5];
-	uint64_t chunk_offsets[5];
-	int num_chunks;
-	int num_extra_edges;
-	struct commit_list *parent;
-	struct progress *progress = NULL;
-	const unsigned hashsz = the_hash_algo->rawsz;
-	uint64_t progress_cnt = 0;
+	uint32_t i;
 	struct strbuf progress_title = STRBUF_INIT;
-	unsigned long approx_nr_objects;
-
-	if (!commit_graph_compatible(the_repository))
-		return;
-
-	oids.nr = 0;
-	approx_nr_objects = approximate_object_count();
-	oids.alloc = approx_nr_objects / 32;
-	oids.progress = NULL;
-	oids.progress_done = 0;
+	struct strbuf packname = STRBUF_INIT;
+	int dirlen;
 
-	if (append) {
-		prepare_commit_graph_one(the_repository, obj_dir);
-		if (the_repository->objects->commit_graph)
-			oids.alloc += the_repository->objects->commit_graph->num_commits;
+	strbuf_addf(&packname, "%s/pack/", ctx->obj_dir);
+	dirlen = packname.len;
+	if (ctx->report_progress) {
+		strbuf_addf(&progress_title,
+			    Q_("Finding commits for commit graph in %d pack",
+			       "Finding commits for commit graph in %d packs",
+			       pack_indexes->nr),
+			    pack_indexes->nr);
+		ctx->progress = start_delayed_progress(progress_title.buf, 0);
+		ctx->progress_done = 0;
 	}
-
-	if (oids.alloc < 1024)
-		oids.alloc = 1024;
-	ALLOC_ARRAY(oids.list, oids.alloc);
-
-	if (append && the_repository->objects->commit_graph) {
-		struct commit_graph *commit_graph =
-			the_repository->objects->commit_graph;
-		for (i = 0; i < commit_graph->num_commits; i++) {
-			const unsigned char *hash = commit_graph->chunk_oid_lookup +
-				commit_graph->hash_len * i;
-			hashcpy(oids.list[oids.nr++].hash, hash);
+	for (i = 0; i < pack_indexes->nr; i++) {
+		struct packed_git *p;
+		strbuf_setlen(&packname, dirlen);
+		strbuf_addstr(&packname, pack_indexes->items[i].string);
+		p = add_packed_git(packname.buf, packname.len, 1);
+		if (!p) {
+			error(_("error adding pack %s"), packname.buf);
+			return -1;
+		}
+		if (open_pack_index(p)) {
+			error(_("error opening index for %s"), packname.buf);
+			return -1;
 		}
+		for_each_object_in_pack(p, add_packed_commits, ctx,
+					FOR_EACH_OBJECT_PACK_ORDER);
+		close_pack(p);
+		free(p);
 	}
 
-	if (pack_indexes) {
-		struct strbuf packname = STRBUF_INIT;
-		int dirlen;
-		strbuf_addf(&packname, "%s/pack/", obj_dir);
-		dirlen = packname.len;
-		if (report_progress) {
-			strbuf_addf(&progress_title,
-				    Q_("Finding commits for commit graph in %d pack",
-				       "Finding commits for commit graph in %d packs",
-				       pack_indexes->nr),
-				    pack_indexes->nr);
-			oids.progress = start_delayed_progress(progress_title.buf, 0);
-			oids.progress_done = 0;
-		}
-		for (i = 0; i < pack_indexes->nr; i++) {
-			struct packed_git *p;
-			strbuf_setlen(&packname, dirlen);
-			strbuf_addstr(&packname, pack_indexes->items[i].string);
-			p = add_packed_git(packname.buf, packname.len, 1);
-			if (!p)
-				die(_("error adding pack %s"), packname.buf);
-			if (open_pack_index(p))
-				die(_("error opening index for %s"), packname.buf);
-			for_each_object_in_pack(p, add_packed_commits, &oids,
-						FOR_EACH_OBJECT_PACK_ORDER);
-			close_pack(p);
-			free(p);
-		}
-		stop_progress(&oids.progress);
-		strbuf_reset(&progress_title);
-		strbuf_release(&packname);
+	stop_progress(&ctx->progress);
+	strbuf_reset(&progress_title);
+	strbuf_release(&packname);
+
+	return 0;
+}
+
+static void fill_oids_from_commit_hex(struct write_commit_graph_context *ctx,
+				      struct string_list *commit_hex)
+{
+	uint32_t i;
+	struct strbuf progress_title = STRBUF_INIT;
+
+	if (ctx->report_progress) {
+		strbuf_addf(&progress_title,
+			    Q_("Finding commits for commit graph from %d ref",
+			       "Finding commits for commit graph from %d refs",
+			       commit_hex->nr),
+			    commit_hex->nr);
+		ctx->progress = start_delayed_progress(
+					progress_title.buf,
+					commit_hex->nr);
 	}
+	for (i = 0; i < commit_hex->nr; i++) {
+		const char *end;
+		struct object_id oid;
+		struct commit *result;
+
+		display_progress(ctx->progress, i + 1);
+		if (commit_hex->items[i].string &&
+		    parse_oid_hex(commit_hex->items[i].string, &oid, &end))
+			continue;
 
-	if (commit_hex) {
-		if (report_progress) {
-			strbuf_addf(&progress_title,
-				    Q_("Finding commits for commit graph from %d ref",
-				       "Finding commits for commit graph from %d refs",
-				       commit_hex->nr),
-				    commit_hex->nr);
-			progress = start_delayed_progress(progress_title.buf,
-							  commit_hex->nr);
-		}
-		for (i = 0; i < commit_hex->nr; i++) {
-			const char *end;
-			struct object_id oid;
-			struct commit *result;
-
-			display_progress(progress, i + 1);
-			if (commit_hex->items[i].string &&
-			    parse_oid_hex(commit_hex->items[i].string, &oid, &end))
-				continue;
-
-			result = lookup_commit_reference_gently(the_repository, &oid, 1);
-
-			if (result) {
-				ALLOC_GROW(oids.list, oids.nr + 1, oids.alloc);
-				oidcpy(&oids.list[oids.nr], &(result->object.oid));
-				oids.nr++;
-			}
+		result = lookup_commit_reference_gently(ctx->r, &oid, 1);
+
+		if (result) {
+			ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
+			oidcpy(&ctx->oids.list[ctx->oids.nr], &(result->object.oid));
+			ctx->oids.nr++;
 		}
-		stop_progress(&progress);
-		strbuf_reset(&progress_title);
 	}
+	stop_progress(&ctx->progress);
+	strbuf_release(&progress_title);
+}
 
-	if (!pack_indexes && !commit_hex) {
-		if (report_progress)
-			oids.progress = start_delayed_progress(
-				_("Finding commits for commit graph among packed objects"),
-				approx_nr_objects);
-		for_each_packed_object(add_packed_commits, &oids,
-				       FOR_EACH_OBJECT_PACK_ORDER);
-		if (oids.progress_done < approx_nr_objects)
-			display_progress(oids.progress, approx_nr_objects);
-		stop_progress(&oids.progress);
-	}
+static void fill_oids_from_all_packs(struct write_commit_graph_context *ctx)
+{
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
+			_("Finding commits for commit graph among packed objects"),
+			ctx->approx_nr_objects);
+	for_each_packed_object(add_packed_commits, ctx,
+			       FOR_EACH_OBJECT_PACK_ORDER);
+	if (ctx->progress_done < ctx->approx_nr_objects)
+		display_progress(ctx->progress, ctx->approx_nr_objects);
+	stop_progress(&ctx->progress);
+}
 
-	close_reachable(&oids, report_progress);
+static uint32_t count_distinct_commits(struct write_commit_graph_context *ctx)
+{
+	uint32_t i, count_distinct = 1;
 
-	if (report_progress)
-		progress = start_delayed_progress(
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
 			_("Counting distinct commits in commit graph"),
-			oids.nr);
-	display_progress(progress, 0); /* TODO: Measure QSORT() progress */
-	QSORT(oids.list, oids.nr, commit_compare);
-	count_distinct = 1;
-	for (i = 1; i < oids.nr; i++) {
-		display_progress(progress, i + 1);
-		if (!oideq(&oids.list[i - 1], &oids.list[i]))
+			ctx->oids.nr);
+	display_progress(ctx->progress, 0); /* TODO: Measure QSORT() progress */
+	QSORT(ctx->oids.list, ctx->oids.nr, commit_compare);
+
+	for (i = 1; i < ctx->oids.nr; i++) {
+		display_progress(ctx->progress, i + 1);
+		if (!oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i]))
 			count_distinct++;
 	}
-	stop_progress(&progress);
+	stop_progress(&ctx->progress);
 
-	if (count_distinct >= GRAPH_EDGE_LAST_MASK)
-		die(_("the commit graph format cannot write %d commits"), count_distinct);
+	return count_distinct;
+}
 
-	commits.nr = 0;
-	commits.alloc = count_distinct;
-	ALLOC_ARRAY(commits.list, commits.alloc);
+static void copy_oids_to_commits(struct write_commit_graph_context *ctx)
+{
+	uint32_t i;
+	struct commit_list *parent;
 
-	num_extra_edges = 0;
-	if (report_progress)
-		progress = start_delayed_progress(
+	ctx->num_extra_edges = 0;
+	if (ctx->report_progress)
+		ctx->progress = start_delayed_progress(
 			_("Finding extra edges in commit graph"),
-			oids.nr);
-	for (i = 0; i < oids.nr; i++) {
+			ctx->oids.nr);
+	for (i = 0; i < ctx->oids.nr; i++) {
 		int num_parents = 0;
-		display_progress(progress, i + 1);
-		if (i > 0 && oideq(&oids.list[i - 1], &oids.list[i]))
+		display_progress(ctx->progress, i + 1);
+		if (i > 0 && oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i]))
 			continue;
 
-		commits.list[commits.nr] = lookup_commit(the_repository, &oids.list[i]);
-		parse_commit_no_graph(commits.list[commits.nr]);
+		ctx->commits.list[ctx->commits.nr] = lookup_commit(ctx->r, &ctx->oids.list[i]);
+		parse_commit_no_graph(ctx->commits.list[ctx->commits.nr]);
 
-		for (parent = commits.list[commits.nr]->parents;
+		for (parent = ctx->commits.list[ctx->commits.nr]->parents;
 		     parent; parent = parent->next)
 			num_parents++;
 
 		if (num_parents > 2)
-			num_extra_edges += num_parents - 1;
+			ctx->num_extra_edges += num_parents - 1;
 
-		commits.nr++;
+		ctx->commits.nr++;
 	}
-	num_chunks = num_extra_edges ? 4 : 3;
-	stop_progress(&progress);
-
-	if (commits.nr >= GRAPH_EDGE_LAST_MASK)
-		die(_("too many commits to write graph"));
-
-	compute_generation_numbers(&commits, report_progress);
+	stop_progress(&ctx->progress);
+}
 
-	graph_name = get_commit_graph_filename(obj_dir);
-	if (safe_create_leading_directories(graph_name)) {
-		UNLEAK(graph_name);
-		die_errno(_("unable to create leading directories of %s"),
-			  graph_name);
+static int write_commit_graph_file(struct write_commit_graph_context *ctx)
+{
+	uint32_t i;
+	struct hashfile *f;
+	struct lock_file lk = LOCK_INIT;
+	uint32_t chunk_ids[5];
+	uint64_t chunk_offsets[5];
+	const unsigned hashsz = the_hash_algo->rawsz;
+	struct strbuf progress_title = STRBUF_INIT;
+	int num_chunks = ctx->num_extra_edges ? 4 : 3;
+
+	ctx->graph_name = get_commit_graph_filename(ctx->obj_dir);
+	if (safe_create_leading_directories(ctx->graph_name)) {
+		UNLEAK(ctx->graph_name);
+		error(_("unable to create leading directories of %s"),
+			ctx->graph_name);
+		return -1;
 	}
 
-	hold_lock_file_for_update(&lk, graph_name, LOCK_DIE_ON_ERROR);
+	hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR);
 	f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
 
 	hashwrite_be32(f, GRAPH_SIGNATURE);
@@ -1071,7 +1054,7 @@ void write_commit_graph(const char *obj_dir,
 	chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
 	chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
 	chunk_ids[2] = GRAPH_CHUNKID_DATA;
-	if (num_extra_edges)
+	if (ctx->num_extra_edges)
 		chunk_ids[3] = GRAPH_CHUNKID_EXTRAEDGES;
 	else
 		chunk_ids[3] = 0;
@@ -1079,9 +1062,9 @@ void write_commit_graph(const char *obj_dir,
 
 	chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
 	chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
-	chunk_offsets[2] = chunk_offsets[1] + hashsz * commits.nr;
-	chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * commits.nr;
-	chunk_offsets[4] = chunk_offsets[3] + 4 * num_extra_edges;
+	chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
+	chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
+	chunk_offsets[4] = chunk_offsets[3] + 4 * ctx->num_extra_edges;
 
 	for (i = 0; i <= num_chunks; i++) {
 		uint32_t chunk_write[3];
@@ -1092,31 +1075,113 @@ void write_commit_graph(const char *obj_dir,
 		hashwrite(f, chunk_write, 12);
 	}
 
-	if (report_progress) {
+	if (ctx->report_progress) {
 		strbuf_addf(&progress_title,
 			    Q_("Writing out commit graph in %d pass",
 			       "Writing out commit graph in %d passes",
 			       num_chunks),
 			    num_chunks);
-		progress = start_delayed_progress(
+		ctx->progress = start_delayed_progress(
 			progress_title.buf,
-			num_chunks * commits.nr);
+			num_chunks * ctx->commits.nr);
 	}
-	write_graph_chunk_fanout(f, commits.list, commits.nr, progress, &progress_cnt);
-	write_graph_chunk_oids(f, hashsz, commits.list, commits.nr, progress, &progress_cnt);
-	write_graph_chunk_data(f, hashsz, commits.list, commits.nr, progress, &progress_cnt);
-	if (num_extra_edges)
-		write_graph_chunk_extra_edges(f, commits.list, commits.nr, progress, &progress_cnt);
-	stop_progress(&progress);
+	write_graph_chunk_fanout(f, ctx);
+	write_graph_chunk_oids(f, hashsz, ctx);
+	write_graph_chunk_data(f, hashsz, ctx);
+	if (ctx->num_extra_edges)
+		write_graph_chunk_extra_edges(f, ctx);
+	stop_progress(&ctx->progress);
 	strbuf_release(&progress_title);
 
-	close_commit_graph(the_repository);
+	close_commit_graph(ctx->r->objects);
 	finalize_hashfile(f, NULL, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
 	commit_lock_file(&lk);
 
-	free(graph_name);
-	free(commits.list);
-	free(oids.list);
+	return 0;
+}
+
+int write_commit_graph(const char *obj_dir,
+		       struct string_list *pack_indexes,
+		       struct string_list *commit_hex,
+		       unsigned int flags)
+{
+	struct write_commit_graph_context *ctx;
+	uint32_t i, count_distinct = 0;
+	int res = 0;
+
+	if (!commit_graph_compatible(the_repository))
+		return 0;
+
+	ctx = xcalloc(1, sizeof(struct write_commit_graph_context));
+	ctx->r = the_repository;
+	ctx->obj_dir = obj_dir;
+	ctx->append = flags & COMMIT_GRAPH_APPEND ? 1 : 0;
+	ctx->report_progress = flags & COMMIT_GRAPH_PROGRESS ? 1 : 0;
+
+	ctx->approx_nr_objects = approximate_object_count();
+	ctx->oids.alloc = ctx->approx_nr_objects / 32;
+
+	if (ctx->append) {
+		prepare_commit_graph_one(ctx->r, ctx->obj_dir);
+		if (ctx->r->objects->commit_graph)
+			ctx->oids.alloc += ctx->r->objects->commit_graph->num_commits;
+	}
+
+	if (ctx->oids.alloc < 1024)
+		ctx->oids.alloc = 1024;
+	ALLOC_ARRAY(ctx->oids.list, ctx->oids.alloc);
+
+	if (ctx->append && ctx->r->objects->commit_graph) {
+		struct commit_graph *g = ctx->r->objects->commit_graph;
+		for (i = 0; i < g->num_commits; i++) {
+			const unsigned char *hash = g->chunk_oid_lookup + g->hash_len * i;
+			hashcpy(ctx->oids.list[ctx->oids.nr++].hash, hash);
+		}
+	}
+
+	if (pack_indexes) {
+		if ((res = fill_oids_from_packs(ctx, pack_indexes)))
+			goto cleanup;
+	}
+
+	if (commit_hex)
+		fill_oids_from_commit_hex(ctx, commit_hex);
+
+	if (!pack_indexes && !commit_hex)
+		fill_oids_from_all_packs(ctx);
+
+	close_reachable(ctx);
+
+	count_distinct = count_distinct_commits(ctx);
+
+	if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
+		error(_("the commit graph format cannot write %d commits"), count_distinct);
+		res = -1;
+		goto cleanup;
+	}
+
+	ctx->commits.alloc = count_distinct;
+	ALLOC_ARRAY(ctx->commits.list, ctx->commits.alloc);
+
+	copy_oids_to_commits(ctx);
+
+	if (ctx->commits.nr >= GRAPH_EDGE_LAST_MASK) {
+		error(_("too many commits to write graph"));
+		res = -1;
+		goto cleanup;
+	}
+
+	compute_generation_numbers(ctx);
+
+	res = write_commit_graph_file(ctx);
+
+cleanup:
+	free(ctx->graph_name);
+	free(ctx->commits.list);
+	free(ctx->oids.list);
+	free(ctx);
+
+	return res;
 }
 
 #define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
@@ -1214,7 +1279,7 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g)
 		hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
 
 		graph_commit = lookup_commit(r, &cur_oid);
-		odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
+		odb_commit = (struct commit *)create_object(r, &cur_oid, alloc_commit_node(r));
 		if (parse_commit_internal(odb_commit, 0, 0)) {
 			graph_report(_("failed to parse commit %s from object database for commit-graph"),
 				     oid_to_hex(&cur_oid));
diff --git a/commit-graph.h b/commit-graph.h
index 7dfb8c896f..390c7f6961 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -65,16 +65,24 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
  */
 int generation_numbers_enabled(struct repository *r);
 
-void write_commit_graph_reachable(const char *obj_dir, int append,
-				  int report_progress);
-void write_commit_graph(const char *obj_dir,
-			struct string_list *pack_indexes,
-			struct string_list *commit_hex,
-			int append, int report_progress);
+#define COMMIT_GRAPH_APPEND     (1 << 0)
+#define COMMIT_GRAPH_PROGRESS   (1 << 1)
+
+/*
+ * The write_commit_graph* methods return zero on success
+ * and a negative value on failure. Note that if the repository
+ * is not compatible with the commit-graph feature, then the
+ * methods will return 0 without writing a commit-graph.
+ */
+int write_commit_graph_reachable(const char *obj_dir, unsigned int flags);
+int write_commit_graph(const char *obj_dir,
+		       struct string_list *pack_indexes,
+		       struct string_list *commit_hex,
+		       unsigned int flags);
 
 int verify_commit_graph(struct repository *r, struct commit_graph *g);
 
-void close_commit_graph(struct repository *);
+void close_commit_graph(struct raw_object_store *);
 void free_commit_graph(struct commit_graph *);
 
 #endif
diff --git a/commit.c b/commit.c
index 8fa1883c61..a98de16e3d 100644
--- a/commit.c
+++ b/commit.c
@@ -57,10 +57,9 @@ struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref
 
 struct commit *lookup_commit(struct repository *r, const struct object_id *oid)
 {
-	struct object *obj = lookup_object(r, oid->hash);
+	struct object *obj = lookup_object(r, oid);
 	if (!obj)
-		return create_object(r, oid->hash,
-				     alloc_commit_node(r));
+		return create_object(r, oid, alloc_commit_node(r));
 	return object_as_type(r, obj, OBJ_COMMIT, 0);
 }
 
@@ -449,7 +448,7 @@ int parse_commit_buffer(struct repository *r, struct commit *item, const void *b
 	item->date = parse_commit_date(bufptr, tail);
 
 	if (check_graph)
-		load_commit_graph_info(the_repository, item);
+		load_commit_graph_info(r, item);
 
 	return 0;
 }
diff --git a/compat/mingw.c b/compat/mingw.c
index 9b6d2400e1..433838391f 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1553,7 +1553,10 @@ static int try_shell_exec(const char *cmd, char *const *argv)
 	if (prog) {
 		int exec_id;
 		int argc = 0;
-		const char **argv2;
+#ifndef _MSC_VER
+		const
+#endif
+		char **argv2;
 		while (argv[argc]) argc++;
 		ALLOC_ARRAY(argv2, argc + 1);
 		argv2[0] = (char *)cmd;	/* full path to the script file */
@@ -2116,8 +2119,33 @@ int mingw_raise(int sig)
 			sigint_fn(SIGINT);
 		return 0;
 
+#if defined(_MSC_VER)
+	case SIGILL:
+	case SIGFPE:
+	case SIGSEGV:
+	case SIGTERM:
+	case SIGBREAK:
+	case SIGABRT:
+	case SIGABRT_COMPAT:
+		/*
+		 * The <signal.h> header in the MS C Runtime defines 8 signals
+		 * as being supported on the platform. Anything else causes an
+		 * "Invalid signal or error" (which in DEBUG builds causes the
+		 * Abort/Retry/Ignore dialog). We by-pass the CRT for things we
+		 * already know will fail.
+		 */
+		return raise(sig);
+	default:
+		errno = EINVAL;
+		return -1;
+
+#else
+
 	default:
 		return raise(sig);
+
+#endif
+
 	}
 }
 
@@ -2301,18 +2329,13 @@ static void setup_windows_environment(void)
 		setenv("TERM", "cygwin", 1);
 }
 
+#if !defined(_MSC_VER)
 /*
  * Disable MSVCRT command line wildcard expansion (__getmainargs called from
  * mingw startup code, see init.c in mingw runtime).
  */
 int _CRT_glob = 0;
-
-typedef struct {
-	int newmode;
-} _startupinfo;
-
-extern int __wgetmainargs(int *argc, wchar_t ***argv, wchar_t ***env, int glob,
-		_startupinfo *si);
+#endif
 
 static NORETURN void die_startup(void)
 {
@@ -2390,21 +2413,40 @@ static void maybe_redirect_std_handles(void)
 				  GENERIC_WRITE, FILE_FLAG_NO_BUFFERING);
 }
 
-void mingw_startup(void)
+#ifdef _MSC_VER
+#ifdef _DEBUG
+#include <crtdbg.h>
+#endif
+#endif
+
+/*
+ * We implement wmain() and compile with -municode, which would
+ * normally ignore main(), but we call the latter from the former
+ * so that we can handle non-ASCII command-line parameters
+ * appropriately.
+ *
+ * To be more compatible with the core git code, we convert
+ * argv into UTF8 and pass them directly to main().
+ */
+int wmain(int argc, const wchar_t **wargv)
 {
-	int i, maxlen, argc;
-	char *buffer;
-	wchar_t **wenv, **wargv;
-	_startupinfo si;
+	int i, maxlen, exit_status;
+	char *buffer, **save;
+	const char **argv;
 
 	trace2_initialize_clock();
 
-	maybe_redirect_std_handles();
+#ifdef _MSC_VER
+#ifdef _DEBUG
+	_CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_DEBUG);
+#endif
 
-	/* get wide char arguments and environment */
-	si.newmode = 0;
-	if (__wgetmainargs(&argc, &wargv, &wenv, _CRT_glob, &si) < 0)
-		die_startup();
+#ifdef USE_MSVC_CRTDBG
+	_CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);
+#endif
+#endif
+
+	maybe_redirect_std_handles();
 
 	/* determine size of argv and environ conversion buffer */
 	maxlen = wcslen(wargv[0]);
@@ -2415,9 +2457,16 @@ void mingw_startup(void)
 	maxlen = 3 * maxlen + 1;
 	buffer = malloc_startup(maxlen);
 
-	/* convert command line arguments and environment to UTF-8 */
+	/*
+	 * Create a UTF-8 version of w_argv. Also create a "save" copy
+	 * to remember all the string pointers because parse_options()
+	 * will remove claimed items from the argv that we pass down.
+	 */
+	ALLOC_ARRAY(argv, argc + 1);
+	ALLOC_ARRAY(save, argc + 1);
 	for (i = 0; i < argc; i++)
-		__argv[i] = wcstoutfdup_startup(buffer, wargv[i], maxlen);
+		argv[i] = save[i] = wcstoutfdup_startup(buffer, wargv[i], maxlen);
+	argv[i] = save[i] = NULL;
 	free(buffer);
 
 	/* fix Windows specific environment settings */
@@ -2436,6 +2485,16 @@ void mingw_startup(void)
 
 	/* initialize Unicode console */
 	winansi_init();
+
+	/* invoke the real main() using our utf8 version of argv. */
+	exit_status = main(argc, argv);
+
+	for (i = 0; i < argc; i++)
+		free(save[i]);
+	free(save);
+	free(argv);
+
+	return exit_status;
 }
 
 int uname(struct utsname *buf)
diff --git a/compat/mingw.h b/compat/mingw.h
index 593bdbffe6..a03e40e6e2 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -352,11 +352,13 @@ static inline int getrlimit(int resource, struct rlimit *rlp)
 #ifndef __MINGW64_VERSION_MAJOR
 #define off_t off64_t
 #define lseek _lseeki64
+#ifndef _MSC_VER
 struct timespec {
 	time_t tv_sec;
 	long tv_nsec;
 };
 #endif
+#endif
 
 struct mingw_stat {
     _dev_t st_dev;
@@ -562,18 +564,18 @@ int xwcstoutf(char *utf, const wchar_t *wcs, size_t utflen);
 extern CRITICAL_SECTION pinfo_cs;
 
 /*
- * A replacement of main() that adds win32 specific initialization.
+ * Git, like most portable C applications, implements a main() function. On
+ * Windows, this main() function would receive parameters encoded in the
+ * current locale, but Git for Windows would prefer UTF-8 encoded  parameters.
+ *
+ * To make that happen, we still declare main() here, and then declare and
+ * implement wmain() (which is the Unicode variant of main()) and compile with
+ * -municode. This wmain() function reencodes the parameters from UTF-16 to
+ * UTF-8 format, sets up a couple of other things as required on Windows, and
+ * then hands off to the main() function.
  */
-
-void mingw_startup(void);
-#define main(c,v) dummy_decl_mingw_main(void); \
-static int mingw_main(c,v); \
-int main(int argc, const char **argv) \
-{ \
-	mingw_startup(); \
-	return mingw_main(__argc, (void *)__argv); \
-} \
-static int mingw_main(c,v)
+int wmain(int argc, const wchar_t **w_argv);
+int main(int argc, const char **argv);
 
 /*
  * Used by Pthread API implementation for Windows
diff --git a/compat/msvc.h b/compat/msvc.h
index 29a8ce8204..1d7a8c6145 100644
--- a/compat/msvc.h
+++ b/compat/msvc.h
@@ -6,6 +6,10 @@
 #include <malloc.h>
 #include <io.h>
 
+#pragma warning(disable: 4018) /* signed/unsigned comparison */
+#pragma warning(disable: 4244) /* type conversion, possible loss of data */
+#pragma warning(disable: 4090) /* 'function' : different 'const' qualifiers (ALLOC_GROW etc.)*/
+
 /* porting function */
 #define inline __inline
 #define __inline__ __inline
@@ -18,6 +22,12 @@
 
 #undef ERROR
 
+#define ftello _ftelli64
+
+typedef int sigset_t;
+/* open for reading, writing, or both (not in fcntl.h) */
+#define O_ACCMODE     (_O_RDONLY | _O_WRONLY | _O_RDWR)
+
 #include "compat/mingw.h"
 
 #endif
diff --git a/compat/obstack.h b/compat/obstack.h
index ced94d0118..ae36ed6a66 100644
--- a/compat/obstack.h
+++ b/compat/obstack.h
@@ -496,7 +496,7 @@ __extension__								\
 ( (h)->temp.tempint = (char *) (obj) - (char *) (h)->chunk,		\
   ((((h)->temp.tempint > 0						\
     && (h)->temp.tempint < (h)->chunk_limit - (char *) (h)->chunk))	\
-   ? (int) ((h)->next_free = (h)->object_base				\
+   ? (ptrdiff_t) ((h)->next_free = (h)->object_base				\
 	    = (h)->temp.tempint + (char *) (h)->chunk)			\
    : (((obstack_free) ((h), (h)->temp.tempint + (char *) (h)->chunk), 0), 0)))
 
diff --git a/compat/poll/poll.c b/compat/poll/poll.c
index 4459408c7d..8b07edb0fe 100644
--- a/compat/poll/poll.c
+++ b/compat/poll/poll.c
@@ -149,7 +149,7 @@ win32_compute_revents (HANDLE h, int *p_sought)
     case FILE_TYPE_PIPE:
       if (!once_only)
 	{
-	  NtQueryInformationFile = (PNtQueryInformationFile)
+	  NtQueryInformationFile = (PNtQueryInformationFile)(void (*)(void))
 	    GetProcAddress (GetModuleHandle ("ntdll.dll"),
 			    "NtQueryInformationFile");
 	  once_only = TRUE;
diff --git a/compat/vcbuild/.gitignore b/compat/vcbuild/.gitignore
new file mode 100644
index 0000000000..8f8b794ef3
--- /dev/null
+++ b/compat/vcbuild/.gitignore
@@ -0,0 +1,3 @@
+/vcpkg/
+/MSVC-DEFS-GEN
+/VCPKG-DEFS
diff --git a/compat/vcbuild/README b/compat/vcbuild/README
index 60fd873fe8..b633e7db98 100644
--- a/compat/vcbuild/README
+++ b/compat/vcbuild/README
@@ -1,3 +1,42 @@
+The Steps to Build Git with VS2015 or VS2017 from the command line.
+
+1. Install the "vcpkg" open source package manager and build essential
+   third-party libraries.  The steps for this have been captured in a
+   set of convenience scripts.  These can be run from a stock Command
+   Prompt or from an SDK bash window:
+
+   $ cd <repo_root>
+   $ ./compat/vcbuild/vcpkg_install.bat
+
+   The vcpkg tools and all of the third-party sources will be installed
+   in this folder:
+      <repo_root>/compat/vcbuild/vcpkg/
+
+   A file will be created with a set of Makefile macros pointing to a
+   unified "include", "lib", and "bin" directory (release and debug) for
+   all of the required packages.  This file will be included by the main
+   Makefile:
+      <repo_root>/compat/vcbuild/MSVC-DEFS-GEN
+
+2. OPTIONALLY copy the third-party *.dll and *.pdb files into the repo
+   root to make it easier to run and debug git.exe without having to
+   manipulate your PATH.  This is especially true for debug sessions in
+   Visual Studio.
+
+   Use ONE of the following forms which should match how you want to
+   compile git.exe.
+
+   $ ./compat/vcbuild/vcpkg_copy_packages.bat debug
+   $ ./compat/vcbuild/vcpkg_copy_packages.bat release
+
+3. Build git using MSVC from an SDK bash window using one of the
+   following commands:
+
+   $ make MSVC=1
+   $ make MSVC=1 DEBUG=1
+
+================================================================
+
 The Steps of Build Git with VS2008
 
 1. You need the build environment, which contains the Git dependencies
diff --git a/compat/vcbuild/find_vs_env.bat b/compat/vcbuild/find_vs_env.bat
new file mode 100644
index 0000000000..40194dd230
--- /dev/null
+++ b/compat/vcbuild/find_vs_env.bat
@@ -0,0 +1,168 @@
+@ECHO OFF
+REM ================================================================
+REM You can use either GCC (the default) or MSVC to build git
+REM using the GIT-SDK command line tools.
+REM        $ make
+REM        $ make MSVC=1
+REM
+REM GIT-SDK BASH windows inherit environment variables with all of
+REM the bin/lib/include paths for GCC.  It DOES NOT inherit values
+REM for the corresponding MSVC tools.
+REM
+REM During normal (non-git) Windows development, you launch one
+REM of the provided "developer command prompts" to set environment
+REM variables for the MSVC tools.
+REM
+REM Therefore, to allow MSVC command line builds of git from BASH
+REM and MAKE, we must blend these two different worlds.  This script
+REM attempts to do that.
+REM ================================================================
+REM This BAT file starts in a plain (non-developer) command prompt,
+REM searches for the "best" commmand prompt setup script, installs
+REM it into the current CMD process, and exports the various MSVC
+REM environment variables for use by MAKE.
+REM
+REM The output of this script should be written to a make "include
+REM file" and referenced by the top-level Makefile.
+REM
+REM See "config.mak.uname" (look for compat/vcbuild/MSVC-DEFS-GEN).
+REM ================================================================
+REM The provided command prompts are custom to each VS release and
+REM filled with lots of internal knowledge (such as Registry settings);
+REM even their names vary by release, so it is not appropriate for us
+REM to look inside them.  Rather, just run them in a subordinate
+REM process and extract the settings we need.
+REM ================================================================
+REM
+REM Current (VS2017 and beyond)
+REM -------------------
+REM Visual Studio 2017 introduced a new installation layout and
+REM support for side-by-side installation of multiple versions of
+REM VS2017.  Furthermore, these can all coexist with installations
+REM of previous versions of VS (which have a completely different
+REM layout on disk).
+REM
+REM VS2017 Update 2 introduced a "vswhere.exe" command:
+REM https://github.com/Microsoft/vswhere
+REM https://blogs.msdn.microsoft.com/heaths/2017/02/25/vswhere-available/
+REM https://blogs.msdn.microsoft.com/vcblog/2017/03/06/finding-the-visual-c-compiler-tools-in-visual-studio-2017/
+REM
+REM VS2015
+REM ------
+REM Visual Studio 2015 uses the traditional VcVarsAll.
+REM
+REM Earlier Versions
+REM ----------------
+REM Currently unsupported.
+REM
+REM ================================================================
+REM Note: Throughout this script we use "dir <path> && <cmd>" rather
+REM than "if exist <path>" because of script problems with pathnames
+REM containing spaces.
+REM ================================================================
+
+REM Sanitize PATH to prevent git-sdk paths from confusing "wmic.exe"
+REM (called internally in some of the system BAT files).
+SET PATH=%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;
+
+REM ================================================================
+
+:current
+   SET vs_where=C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe
+   dir "%vs_where%" >nul 2>nul && GOTO have_vs_where
+   GOTO not_2017
+
+:have_vs_where
+   REM Try to use VsWhere to get the location of VsDevCmd.
+
+   REM Keep VsDevCmd from cd'ing away.
+   SET VSCMD_START_DIR=.
+
+   REM Get the root of the VS product installation.
+   FOR /F "usebackq tokens=*" %%i IN (`"%vs_where%" -latest -requires Microsoft.VisualStudio.Workload.NativeDesktop -property installationPath`) DO @SET vs_ip=%%i
+
+   SET vs_devcmd=%vs_ip%\Common7\Tools\VsDevCmd.bat
+   dir "%vs_devcmd%" >nul 2>nul && GOTO have_vs_devcmd
+   GOTO not_2017
+
+:have_vs_devcmd
+   REM Use VsDevCmd to setup the environment of this process.
+   REM Setup CL for building 64-bit apps using 64-bit tools.
+   @call "%vs_devcmd%" -no_logo -arch=x64 -host_arch=x64
+
+   SET tgt=%VSCMD_ARG_TGT_ARCH%
+
+   SET mn=%VCToolsInstallDir%
+   SET msvc_includes=-I"%mn%INCLUDE"
+   SET msvc_libs=-L"%mn%lib\%tgt%"
+   SET msvc_bin_dir=%mn%bin\Host%VSCMD_ARG_HOST_ARCH%\%tgt%
+
+   SET sdk_dir=%WindowsSdkDir%
+   SET sdk_ver=%WindowsSDKVersion%
+   SET si=%sdk_dir%Include\%sdk_ver%
+   SET sdk_includes=-I"%si%ucrt" -I"%si%um" -I"%si%shared"
+   SET sl=%sdk_dir%lib\%sdk_ver%
+   SET sdk_libs=-L"%sl%ucrt\%tgt%" -L"%sl%um\%tgt%"
+
+   SET vs_ver=%VisualStudioVersion%
+
+   GOTO print_vars
+
+REM ================================================================
+
+:not_2017
+   REM See if VS2015 is installed.
+
+   SET vs_2015_bat=C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat
+   dir "%vs_2015_bat%" >nul 2>nul && GOTO have_vs_2015
+   GOTO not_2015
+
+:have_vs_2015
+   REM Use VcVarsAll like the "x64 Native" command prompt.
+   REM Setup CL for building 64-bit apps using 64-bit tools.
+   @call "%vs_2015_bat%" amd64
+
+   REM Note that in VS2015 they use "x64" in some contexts and "amd64" in others.
+   SET mn=C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\
+   SET msvc_includes=-I"%mn%INCLUDE"
+   SET msvc_libs=-L"%mn%lib\amd64"
+   SET msvc_bin_dir=%mn%bin\amd64
+
+   SET sdk_dir=%WindowsSdkDir%
+   SET sdk_ver=%WindowsSDKVersion%
+   SET si=%sdk_dir%Include\%sdk_ver%
+   SET sdk_includes=-I"%si%ucrt" -I"%si%um" -I"%si%shared" -I"%si%winrt"
+   SET sl=%sdk_dir%lib\%sdk_ver%
+   SET sdk_libs=-L"%sl%ucrt\x64" -L"%sl%um\x64"
+
+   SET vs_ver=%VisualStudioVersion%
+
+   GOTO print_vars
+
+REM ================================================================
+
+:not_2015
+   echo "ERROR: unsupported VS version (older than VS2015)" >&2
+   EXIT /B 1
+
+REM ================================================================
+
+:print_vars
+   REM Dump the essential vars to stdout to allow the main
+   REM Makefile to include it.  See config.mak.uname.
+   REM Include DOS-style and BASH-style path for bin dir.
+
+   echo msvc_bin_dir=%msvc_bin_dir%
+   SET X1=%msvc_bin_dir:C:=/C%
+   SET X2=%X1:\=/%
+   echo msvc_bin_dir_msys=%X2%
+
+   echo msvc_includes=%msvc_includes%
+   echo msvc_libs=%msvc_libs%
+
+   echo sdk_includes=%sdk_includes%
+   echo sdk_libs=%sdk_libs%
+
+   echo vs_ver=%vs_ver%
+
+   EXIT /B 0
diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl
index a87d0da512..c7b021bfac 100755
--- a/compat/vcbuild/scripts/clink.pl
+++ b/compat/vcbuild/scripts/clink.pl
@@ -12,32 +12,62 @@
 use strict;
 my @args = ();
 my @cflags = ();
+my @lflags = ();
 my $is_linking = 0;
+my $is_debug = 0;
 while (@ARGV) {
 	my $arg = shift @ARGV;
-	if ("$arg" =~ /^-[DIMGO]/) {
+	if ("$arg" eq "-DDEBUG") {
+	    # Some vcpkg-based libraries have different names for release
+	    # and debug versions.  This hack assumes that -DDEBUG comes
+	    # before any "-l*" flags.
+	    $is_debug = 1;
+	}
+	if ("$arg" =~ /^-[DIMGOZ]/) {
 		push(@cflags, $arg);
 	} elsif ("$arg" eq "-o") {
 		my $file_out = shift @ARGV;
 		if ("$file_out" =~ /exe$/) {
 			$is_linking = 1;
+			# Create foo.exe and foo.pdb
 			push(@args, "-OUT:$file_out");
 		} else {
+			# Create foo.o and foo.o.pdb
 			push(@args, "-Fo$file_out");
+			push(@args, "-Fd$file_out.pdb");
 		}
 	} elsif ("$arg" eq "-lz") {
+	    if ($is_debug) {
+		push(@args, "zlibd.lib");
+	    } else{
 		push(@args, "zlib.lib");
+	    }
 	} elsif ("$arg" eq "-liconv") {
-		push(@args, "iconv.lib");
+		push(@args, "libiconv.lib");
 	} elsif ("$arg" eq "-lcrypto") {
 		push(@args, "libeay32.lib");
 	} elsif ("$arg" eq "-lssl") {
 		push(@args, "ssleay32.lib");
 	} elsif ("$arg" eq "-lcurl") {
-		push(@args, "libcurl.lib");
+		my $lib = "";
+		# Newer vcpkg definitions call this libcurl_imp.lib; Do we
+		# need to use that instead?
+		foreach my $flag (@lflags) {
+			if ($flag =~ /^-LIBPATH:(.*)/) {
+				foreach my $l ("libcurl_imp.lib", "libcurl.lib") {
+					if (-f "$1/$l") {
+						$lib = $l;
+						last;
+					}
+				}
+			}
+		}
+		push(@args, $lib);
+	} elsif ("$arg" eq "-lexpat") {
+		push(@args, "expat.lib");
 	} elsif ("$arg" =~ /^-L/ && "$arg" ne "-LTCG") {
 		$arg =~ s/^-L/-LIBPATH:/;
-		push(@args, $arg);
+		push(@lflags, $arg);
 	} elsif ("$arg" =~ /^-R/) {
 		# eat
 	} else {
@@ -45,10 +75,11 @@
 	}
 }
 if ($is_linking) {
+	push(@args, @lflags);
 	unshift(@args, "link.exe");
 } else {
 	unshift(@args, "cl.exe");
 	push(@args, @cflags);
 }
-#printf("**** @args\n");
+printf(STDERR "**** @args\n\n\n") if (!defined($ENV{'QUIET_GEN'}));
 exit (system(@args) != 0);
diff --git a/compat/vcbuild/vcpkg_copy_dlls.bat b/compat/vcbuild/vcpkg_copy_dlls.bat
new file mode 100644
index 0000000000..13661c14f8
--- /dev/null
+++ b/compat/vcbuild/vcpkg_copy_dlls.bat
@@ -0,0 +1,39 @@
+@ECHO OFF
+REM ================================================================
+REM This script is an optional step. It copies the *.dll and *.pdb
+REM files (created by vcpkg_install.bat) into the top-level directory
+REM of the repo so that you can type "./git.exe" and find them without
+REM having to fixup your PATH.
+REM
+REM NOTE: Because the names of some DLL files change between DEBUG and
+REM NOTE: RELEASE builds when built using "vcpkg.exe", you will need
+REM NOTE: to copy up the corresponding version.
+REM ================================================================
+
+	SETLOCAL EnableDelayedExpansion
+
+	@FOR /F "delims=" %%D IN ("%~dp0") DO @SET cwd=%%~fD
+	cd %cwd%
+
+	SET arch=x64-windows
+	SET inst=%cwd%vcpkg\installed\%arch%
+
+	IF [%1]==[release] (
+		echo Copying RELEASE mode DLLs to repo root...
+	) ELSE IF [%1]==[debug] (
+		SET inst=%inst%\debug
+		echo Copying DEBUG mode DLLs to repo root...
+	) ELSE (
+		echo ERROR: Invalid argument.
+		echo Usage: %~0 release
+		echo Usage: %~0 debug
+		EXIT /B 1
+	)
+
+	xcopy /e/s/v/y %inst%\bin\*.dll ..\..\
+	xcopy /e/s/v/y %inst%\bin\*.pdb ..\..\
+
+	xcopy /e/s/v/y %inst%\bin\*.dll ..\..\t\helper\
+	xcopy /e/s/v/y %inst%\bin\*.pdb ..\..\t\helper\
+
+	EXIT /B 0
diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
new file mode 100644
index 0000000000..ebd0bad242
--- /dev/null
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -0,0 +1,80 @@
+@ECHO OFF
+REM ================================================================
+REM This script installs the "vcpkg" source package manager and uses
+REM it to build the third-party libraries that git requires when it
+REM is built using MSVC.
+REM
+REM [1] Install VCPKG.
+REM     [a] Create <root>/compat/vcbuild/vcpkg/
+REM     [b] Download "vcpkg".
+REM     [c] Compile using the currently installed version of VS.
+REM     [d] Create <root>/compat/vcbuild/vcpkg/vcpkg.exe
+REM
+REM [2] Install third-party libraries.
+REM     [a] Download each (which may also install CMAKE).
+REM     [b] Compile in RELEASE mode and install in:
+REM         vcpkg/installed/<arch>/{bin,lib}
+REM     [c] Compile in DEBUG mode and install in:
+REM         vcpkg/installed/<arch>/debug/{bin,lib}
+REM     [d] Install headers in:
+REM         vcpkg/installed/<arch>/include
+REM
+REM [3] Create a set of MAKE definitions for the top-level
+REM     Makefile to allow "make MSVC=1" to find the above
+REM     third-party libraries.
+REM     [a] Write vcpkg/VCPGK-DEFS
+REM
+REM https://blogs.msdn.microsoft.com/vcblog/2016/09/19/vcpkg-a-tool-to-acquire-and-build-c-open-source-libraries-on-windows/
+REM https://github.com/Microsoft/vcpkg
+REM https://vcpkg.readthedocs.io/en/latest/
+REM ================================================================
+
+	SETLOCAL EnableDelayedExpansion
+
+	@FOR /F "delims=" %%D IN ("%~dp0") DO @SET cwd=%%~fD
+	cd %cwd%
+
+	dir vcpkg\vcpkg.exe >nul 2>nul && GOTO :install_libraries
+
+	echo Fetching vcpkg in %cwd%vcpkg
+	git.exe clone https://github.com/Microsoft/vcpkg vcpkg
+	IF ERRORLEVEL 1 ( EXIT /B 1 )
+
+	cd vcpkg
+	echo Building vcpkg
+	powershell -exec bypass scripts\bootstrap.ps1
+	IF ERRORLEVEL 1 ( EXIT /B 1 )
+
+	echo Successfully installed %cwd%vcpkg\vcpkg.exe
+
+:install_libraries
+	SET arch=x64-windows
+
+	echo Installing third-party libraries...
+	FOR %%i IN (zlib expat libiconv openssl libssh2 curl) DO (
+	    cd %cwd%vcpkg
+	    IF NOT EXIST "packages\%%i_%arch%" CALL :sub__install_one %%i
+	    IF ERRORLEVEL 1 ( EXIT /B 1 )
+	)
+
+:install_defines
+	cd %cwd%
+	SET inst=%cwd%vcpkg\installed\%arch%
+
+	echo vcpkg_inc=-I"%inst%\include">VCPKG-DEFS
+	echo vcpkg_rel_lib=-L"%inst%\lib">>VCPKG-DEFS
+	echo vcpkg_rel_bin="%inst%\bin">>VCPKG-DEFS
+	echo vcpkg_dbg_lib=-L"%inst%\debug\lib">>VCPKG-DEFS
+	echo vcpkg_dbg_bin="%inst%\debug\bin">>VCPKG-DEFS
+
+	EXIT /B 0
+
+
+:sub__install_one
+	echo     Installing package %1...
+
+	.\vcpkg.exe install %1:%arch%
+	IF ERRORLEVEL 1 ( EXIT /B 1 )
+
+	echo     Finished %1
+	goto :EOF
diff --git a/compat/winansi.c b/compat/winansi.c
index f4f08237f9..efc0abcdac 100644
--- a/compat/winansi.c
+++ b/compat/winansi.c
@@ -7,6 +7,7 @@
 #include <wingdi.h>
 #include <winreg.h>
 #include "win32.h"
+#include "win32/lazyload.h"
 
 static int fd_is_interactive[3] = { 0, 0, 0 };
 #define FD_CONSOLE 0x1
@@ -41,26 +42,21 @@ typedef struct _CONSOLE_FONT_INFOEX {
 #endif
 #endif
 
-typedef BOOL (WINAPI *PGETCURRENTCONSOLEFONTEX)(HANDLE, BOOL,
-		PCONSOLE_FONT_INFOEX);
-
 static void warn_if_raster_font(void)
 {
 	DWORD fontFamily = 0;
-	PGETCURRENTCONSOLEFONTEX pGetCurrentConsoleFontEx;
+	DECLARE_PROC_ADDR(kernel32.dll, BOOL, GetCurrentConsoleFontEx,
+			HANDLE, BOOL, PCONSOLE_FONT_INFOEX);
 
 	/* don't bother if output was ascii only */
 	if (!non_ascii_used)
 		return;
 
 	/* GetCurrentConsoleFontEx is available since Vista */
-	pGetCurrentConsoleFontEx = (PGETCURRENTCONSOLEFONTEX) GetProcAddress(
-			GetModuleHandle("kernel32.dll"),
-			"GetCurrentConsoleFontEx");
-	if (pGetCurrentConsoleFontEx) {
+	if (INIT_PROC_ADDR(GetCurrentConsoleFontEx)) {
 		CONSOLE_FONT_INFOEX cfi;
 		cfi.cbSize = sizeof(cfi);
-		if (pGetCurrentConsoleFontEx(console, 0, &cfi))
+		if (GetCurrentConsoleFontEx(console, 0, &cfi))
 			fontFamily = cfi.FontFamily;
 	} else {
 		/* pre-Vista: check default console font in registry */
@@ -544,7 +540,20 @@ static HANDLE swap_osfhnd(int fd, HANDLE new_handle)
 #ifdef DETECT_MSYS_TTY
 
 #include <winternl.h>
+
+#if defined(_MSC_VER)
+
+typedef struct _OBJECT_NAME_INFORMATION
+{
+	UNICODE_STRING Name;
+	WCHAR NameBuffer[0];
+} OBJECT_NAME_INFORMATION, *POBJECT_NAME_INFORMATION;
+
+#define ObjectNameInformation 1
+
+#else
 #include <ntstatus.h>
+#endif
 
 static void detect_msys_tty(int fd)
 {
diff --git a/config.c b/config.c
index 296a6d9cc4..faa57e436c 100644
--- a/config.c
+++ b/config.c
@@ -19,6 +19,7 @@
 #include "utf8.h"
 #include "dir.h"
 #include "color.h"
+#include "refs.h"
 
 struct config_source {
 	struct config_source *prev;
@@ -170,6 +171,12 @@ static int handle_path_include(const char *path, struct config_include_data *inc
 	return ret;
 }
 
+static void add_trailing_starstar_for_dir(struct strbuf *pat)
+{
+	if (pat->len && is_dir_sep(pat->buf[pat->len - 1]))
+		strbuf_addstr(pat, "**");
+}
+
 static int prepare_include_condition_pattern(struct strbuf *pat)
 {
 	struct strbuf path = STRBUF_INIT;
@@ -199,8 +206,7 @@ static int prepare_include_condition_pattern(struct strbuf *pat)
 	} else if (!is_absolute_path(pat->buf))
 		strbuf_insert(pat, 0, "**/", 3);
 
-	if (pat->len && is_dir_sep(pat->buf[pat->len - 1]))
-		strbuf_addstr(pat, "**");
+	add_trailing_starstar_for_dir(pat);
 
 	strbuf_release(&path);
 	return prefix;
@@ -264,6 +270,25 @@ static int include_by_gitdir(const struct config_options *opts,
 	return ret;
 }
 
+static int include_by_branch(const char *cond, size_t cond_len)
+{
+	int flags;
+	int ret;
+	struct strbuf pattern = STRBUF_INIT;
+	const char *refname = resolve_ref_unsafe("HEAD", 0, NULL, &flags);
+	const char *shortname;
+
+	if (!refname || !(flags & REF_ISSYMREF)	||
+			!skip_prefix(refname, "refs/heads/", &shortname))
+		return 0;
+
+	strbuf_add(&pattern, cond, cond_len);
+	add_trailing_starstar_for_dir(&pattern);
+	ret = !wildmatch(pattern.buf, shortname, WM_PATHNAME);
+	strbuf_release(&pattern);
+	return ret;
+}
+
 static int include_condition_is_true(const struct config_options *opts,
 				     const char *cond, size_t cond_len)
 {
@@ -272,6 +297,8 @@ static int include_condition_is_true(const struct config_options *opts,
 		return include_by_gitdir(opts, cond, cond_len, 0);
 	else if (skip_prefix_mem(cond, cond_len, "gitdir/i:", &cond, &cond_len))
 		return include_by_gitdir(opts, cond, cond_len, 1);
+	else if (skip_prefix_mem(cond, cond_len, "onbranch:", &cond, &cond_len))
+		return include_by_branch(cond, cond_len);
 
 	/* unknown conditionals are always false */
 	return 0;
@@ -834,22 +861,16 @@ static int git_parse_source(config_fn_t fn, void *data,
 	return error_return;
 }
 
-static int parse_unit_factor(const char *end, uintmax_t *val)
+static uintmax_t get_unit_factor(const char *end)
 {
 	if (!*end)
 		return 1;
-	else if (!strcasecmp(end, "k")) {
-		*val *= 1024;
-		return 1;
-	}
-	else if (!strcasecmp(end, "m")) {
-		*val *= 1024 * 1024;
-		return 1;
-	}
-	else if (!strcasecmp(end, "g")) {
-		*val *= 1024 * 1024 * 1024;
-		return 1;
-	}
+	else if (!strcasecmp(end, "k"))
+		return 1024;
+	else if (!strcasecmp(end, "m"))
+		return 1024 * 1024;
+	else if (!strcasecmp(end, "g"))
+		return 1024 * 1024 * 1024;
 	return 0;
 }
 
@@ -859,19 +880,20 @@ static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 		char *end;
 		intmax_t val;
 		uintmax_t uval;
-		uintmax_t factor = 1;
+		uintmax_t factor;
 
 		errno = 0;
 		val = strtoimax(value, &end, 0);
 		if (errno == ERANGE)
 			return 0;
-		if (!parse_unit_factor(end, &factor)) {
+		factor = get_unit_factor(end);
+		if (!factor) {
 			errno = EINVAL;
 			return 0;
 		}
-		uval = labs(val);
-		uval *= factor;
-		if (uval > max || labs(val) > uval) {
+		uval = val < 0 ? -val : val;
+		if (unsigned_mult_overflows(factor, uval) ||
+		    factor * uval > max) {
 			errno = ERANGE;
 			return 0;
 		}
@@ -888,21 +910,23 @@ static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 	if (value && *value) {
 		char *end;
 		uintmax_t val;
-		uintmax_t oldval;
+		uintmax_t factor;
 
 		errno = 0;
 		val = strtoumax(value, &end, 0);
 		if (errno == ERANGE)
 			return 0;
-		oldval = val;
-		if (!parse_unit_factor(end, &val)) {
+		factor = get_unit_factor(end);
+		if (!factor) {
 			errno = EINVAL;
 			return 0;
 		}
-		if (val > max || oldval > val) {
+		if (unsigned_mult_overflows(factor, val) ||
+		    factor * val > max) {
 			errno = ERANGE;
 			return 0;
 		}
+		val *= factor;
 		*ret = val;
 		return 1;
 	}
diff --git a/config.mak.uname b/config.mak.uname
index b71688eeb7..3fde48c64d 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -1,5 +1,9 @@
 # Platform specific Makefile tweaks based on uname detection
 
+# Define NO_SAFESEH if you need MSVC/Visual Studio to ignore the lack of
+# Microsoft's Safe Exception Handling in libraries (such as zlib).
+# Typically required for VS2013+/32-bit compilation on Vista+ versions.
+
 uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
 uname_M := $(shell sh -c 'uname -m 2>/dev/null || echo not')
 uname_O := $(shell sh -c 'uname -o 2>/dev/null || echo not')
@@ -11,6 +15,19 @@ ifdef MSVC
 	# avoid the MingW and Cygwin configuration sections
 	uname_S := Windows
 	uname_O := Windows
+
+	# Generate and include makefile variables that point to the
+	# currently installed set of MSVC command line tools.
+compat/vcbuild/MSVC-DEFS-GEN: compat/vcbuild/find_vs_env.bat
+	@"$<" | tr '\\' / >"$@"
+include compat/vcbuild/MSVC-DEFS-GEN
+
+	# See if vcpkg and the vcpkg-build versions of the third-party
+	# libraries that we use are installed.  We include the result
+	# to get $(vcpkg_*) variables defined for the Makefile.
+compat/vcbuild/VCPKG-DEFS: compat/vcbuild/vcpkg_install.bat
+	@"$<"
+include compat/vcbuild/VCPKG-DEFS
 endif
 
 # We choose to avoid "if .. else if .. else .. endif endif"
@@ -356,6 +373,19 @@ endif
 ifeq ($(uname_S),Windows)
 	GIT_VERSION := $(GIT_VERSION).MSVC
 	pathsep = ;
+	# Assume that this is built in Git for Windows' SDK
+	ifeq (MINGW32,$(MSYSTEM))
+		prefix = /mingw32
+	else
+		prefix = /mingw64
+	endif
+	# Prepend MSVC 64-bit tool-chain to PATH.
+	#
+	# A regular Git Bash *does not* have cl.exe in its $PATH. As there is a
+	# link.exe next to, and required by, cl.exe, we have to prepend this
+	# onto the existing $PATH.
+	#
+	SANE_TOOL_PATH ?= $(msvc_bin_dir_msys)
 	HAVE_ALLOCA_H = YesPlease
 	NO_PREAD = YesPlease
 	NEEDS_CRYPTO_WITH_SSL = YesPlease
@@ -368,11 +398,14 @@ ifeq ($(uname_S),Windows)
 	NO_STRCASESTR = YesPlease
 	NO_STRLCPY = YesPlease
 	NO_MEMMEM = YesPlease
-	# NEEDS_LIBICONV = YesPlease
-	NO_ICONV = YesPlease
+	NEEDS_LIBICONV = YesPlease
 	NO_STRTOUMAX = YesPlease
 	NO_MKDTEMP = YesPlease
-	SNPRINTF_RETURNS_BOGUS = YesPlease
+	NO_INTTYPES_H = YesPlease
+	# VS2015 with UCRT claims that snprintf and friends are C99 compliant,
+	# so we don't need this:
+	#
+	#   SNPRINTF_RETURNS_BOGUS = YesPlease
 	NO_SVN_TESTS = YesPlease
 	RUNTIME_PREFIX = YesPlease
 	HAVE_WPGMPTR = YesWeDo
@@ -385,7 +418,6 @@ ifeq ($(uname_S),Windows)
 	NO_REGEX = YesPlease
 	NO_GETTEXT = YesPlease
 	NO_PYTHON = YesPlease
-	BLK_SHA1 = YesPlease
 	ETAGS_TARGET = ETAGS
 	NO_POSIX_GOODIES = UnfortunatelyYes
 	NATIVE_CRLF = YesPlease
@@ -394,26 +426,52 @@ ifeq ($(uname_S),Windows)
 	CC = compat/vcbuild/scripts/clink.pl
 	AR = compat/vcbuild/scripts/lib.pl
 	CFLAGS =
-	BASIC_CFLAGS = -nologo -I. -I../zlib -Icompat/vcbuild -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
+	BASIC_CFLAGS = -nologo -I. -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
 	COMPAT_OBJS = compat/msvc.o compat/winansi.o \
 		compat/win32/path-utils.o \
 		compat/win32/pthread.o compat/win32/syslog.o \
 		compat/win32/trace2_win32_process_info.o \
 		compat/win32/dirent.o
-	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
-	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -SUBSYSTEM:CONSOLE
-	EXTLIBS = user32.lib advapi32.lib shell32.lib wininet.lib ws2_32.lib invalidcontinue.obj
+	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
+	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -ENTRY:wmainCRTStartup -SUBSYSTEM:CONSOLE
+	# invalidcontinue.obj allows Git's source code to close the same file
+	# handle twice, or to access the osfhandle of an already-closed stdout
+	# See https://msdn.microsoft.com/en-us/library/ms235330.aspx
+	EXTLIBS = user32.lib advapi32.lib shell32.lib wininet.lib ws2_32.lib invalidcontinue.obj kernel32.lib ntdll.lib
 	PTHREAD_LIBS =
 	lib =
+	BASIC_CFLAGS += $(vcpkg_inc) $(sdk_includes) $(msvc_includes)
+ifndef DEBUG
+	BASIC_CFLAGS += $(vcpkg_rel_lib)
+else
+	BASIC_CFLAGS += $(vcpkg_dbg_lib)
+endif
+	BASIC_CFLAGS += $(sdk_libs) $(msvc_libs)
+
+ifneq ($(USE_MSVC_CRTDBG),)
+	# Optionally enable memory leak reporting.
+	BASIC_CFLAGS += -DUSE_MSVC_CRTDBG
+endif
 	BASIC_CFLAGS += -DPROTECT_NTFS_DEFAULT=1
+	# Always give "-Zi" to the compiler and "-debug" to linker (even in
+	# release mode) to force a PDB to be generated (like RelWithDebInfo).
+	BASIC_CFLAGS += -Zi
+	BASIC_LDFLAGS += -debug -Zf
+
+ifdef NO_SAFESEH
+	LDFLAGS += -SAFESEH:NO
+endif
+
 ifndef DEBUG
-	BASIC_CFLAGS += -GL -Os -MD
-	BASIC_LDFLAGS += -LTCG
+	BASIC_CFLAGS += -GL -Gy -O2 -Oy- -MD -DNDEBUG
+	BASIC_LDFLAGS += -release -LTCG /OPT:REF /OPT:ICF /INCREMENTAL:NO /DEBUGTYPE:CV,FIXUP
 	AR += -LTCG
 else
-	BASIC_CFLAGS += -Zi -MDd
+	BASIC_CFLAGS += -MDd -DDEBUG -D_DEBUG
 endif
 	X = .exe
+
+compat/msvc.o: compat/msvc.c compat/mingw.c GIT-CFLAGS
 endif
 ifeq ($(uname_S),Interix)
 	NO_INITGROUPS = YesPlease
@@ -548,6 +606,7 @@ ifneq (,$(findstring MINGW,$(uname_S)))
 	ETAGS_TARGET = ETAGS
 	NO_POSIX_GOODIES = UnfortunatelyYes
 	DEFAULT_HELP_FORMAT = html
+	BASIC_LDFLAGS += -municode
 	COMPAT_CFLAGS += -DNOGDI -Icompat -Icompat/win32
 	COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
 	COMPAT_OBJS += compat/mingw.o compat/winansi.o \
@@ -571,7 +630,7 @@ ifneq (,$(wildcard ../THIS_IS_MSYSGIT))
 	INTERNAL_QSORT = YesPlease
 	HAVE_LIBCHARSET_H = YesPlease
 	NO_GETTEXT = YesPlease
-	COMPAT_CLFAGS += -D__USE_MINGW_ACCESS
+	COMPAT_CFLAGS += -D__USE_MINGW_ACCESS
 else
 	ifneq ($(shell expr "$(uname_R)" : '1\.'),2)
 		# MSys2
diff --git a/configure.ac b/configure.ac
index be3b55f1cc..a43b476402 100644
--- a/configure.ac
+++ b/configure.ac
@@ -475,8 +475,18 @@ else
       if test "$git_cv_ld_rpath" = "yes"; then
          CC_LD_DYNPATH=-rpath
       else
-         CC_LD_DYNPATH=
-         AC_MSG_WARN([linker does not support runtime path to dynamic libraries])
+         AC_CACHE_CHECK([if linker supports -Wl,+b,], git_cv_ld_wl_b, [
+            SAVE_LDFLAGS="${LDFLAGS}"
+            LDFLAGS="${SAVE_LDFLAGS} -Wl,+b,/"
+            AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])], [git_cv_ld_wl_b=yes], [git_cv_ld_wl_b=no])
+            LDFLAGS="${SAVE_LDFLAGS}"
+         ])
+         if test "$git_cv_ld_wl_b" = "yes"; then
+            CC_LD_DYNPATH=-Wl,+b,
+          else
+             CC_LD_DYNPATH=
+             AC_MSG_WARN([linker does not support runtime path to dynamic libraries])
+          fi
       fi
    fi
 fi
diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
index 01586821dc..46b8d2ee11 100644
--- a/contrib/coccinelle/array.cocci
+++ b/contrib/coccinelle/array.cocci
@@ -1,29 +1,60 @@
 @@
-type T;
-T *dst;
-T *src;
-expression n;
+expression dst, src, n, E;
 @@
-- memcpy(dst, src, (n) * sizeof(*dst));
-+ COPY_ARRAY(dst, src, n);
+  memcpy(dst, src, n * sizeof(
+- E[...]
++ *(E)
+  ))
 
 @@
 type T;
-T *dst;
-T *src;
-expression n;
+T *ptr;
+T[] arr;
+expression E, n;
 @@
-- memcpy(dst, src, (n) * sizeof(*src));
-+ COPY_ARRAY(dst, src, n);
+(
+  memcpy(ptr, E,
+- n * sizeof(*(ptr))
++ n * sizeof(T)
+  )
+|
+  memcpy(arr, E,
+- n * sizeof(*(arr))
++ n * sizeof(T)
+  )
+|
+  memcpy(E, ptr,
+- n * sizeof(*(ptr))
++ n * sizeof(T)
+  )
+|
+  memcpy(E, arr,
+- n * sizeof(*(arr))
++ n * sizeof(T)
+  )
+)
 
 @@
 type T;
-T *dst;
-T *src;
+T *dst_ptr;
+T *src_ptr;
+T[] dst_arr;
+T[] src_arr;
 expression n;
 @@
-- memcpy(dst, src, (n) * sizeof(T));
-+ COPY_ARRAY(dst, src, n);
+(
+- memcpy(dst_ptr, src_ptr, (n) * sizeof(T))
++ COPY_ARRAY(dst_ptr, src_ptr, n)
+|
+- memcpy(dst_ptr, src_arr, (n) * sizeof(T))
++ COPY_ARRAY(dst_ptr, src_arr, n)
+|
+- memcpy(dst_arr, src_ptr, (n) * sizeof(T))
++ COPY_ARRAY(dst_arr, src_ptr, n)
+|
+- memcpy(dst_arr, src_arr, (n) * sizeof(T))
++ COPY_ARRAY(dst_arr, src_arr, n)
+)
 
 @@
 type T;
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 9f71bcde96..e087c4bf00 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -37,7 +37,8 @@
 #   GIT_COMPLETION_CHECKOUT_NO_GUESS
 #
 #     When set to "1", do not include "DWIM" suggestions in git-checkout
-#     completion (e.g., completing "foo" when "origin/foo" exists).
+#     and git-switch completion (e.g., completing "foo" when "origin/foo"
+#     exists).
 
 case "$COMP_WORDBREAKS" in
 *:*) : great ;;
@@ -400,7 +401,8 @@ __gitcomp_builtin ()
 	if [ -z "$options" ]; then
 		# leading and trailing spaces are significant to make
 		# option removal work correctly.
-		options=" $incl $(__git ${cmd/_/ } --git-completion-helper) "
+		options=" $incl $(__git ${cmd/_/ } --git-completion-helper) " || return
+
 		for i in $excl; do
 			options="${options/ $i / }"
 		done
@@ -2159,6 +2161,44 @@ _git_status ()
 	__git_complete_index_file "$complete_opt"
 }
 
+_git_switch ()
+{
+	case "$cur" in
+	--conflict=*)
+		__gitcomp "diff3 merge" "" "${cur##--conflict=}"
+		;;
+	--*)
+		__gitcomp_builtin switch
+		;;
+	*)
+		# check if --track, --no-track, or --no-guess was specified
+		# if so, disable DWIM mode
+		local track_opt="--track" only_local_ref=n
+		if [ "$GIT_COMPLETION_CHECKOUT_NO_GUESS" = "1" ] ||
+		   [ -n "$(__git_find_on_cmdline "--track --no-track --no-guess")" ]; then
+			track_opt=''
+		fi
+		# explicit --guess enables DWIM mode regardless of
+		# $GIT_COMPLETION_CHECKOUT_NO_GUESS
+		if [ -n "$(__git_find_on_cmdline "--guess")" ]; then
+			track_opt='--track'
+		fi
+		if [ -z "$(__git_find_on_cmdline "-d --detach")" ]; then
+			only_local_ref=y
+		else
+			# --guess --detach is invalid combination, no
+			# dwim will be done when --detach is specified
+			track_opt=
+		fi
+		if [ $only_local_ref = y -a -z "$track_opt" ]; then
+			__gitcomp_direct "$(__git_heads "" "$cur" " ")"
+		else
+			__git_complete_refs $track_opt
+		fi
+		;;
+	esac
+}
+
 __git_config_get_set_variables ()
 {
 	local prevword word config_file= c=$cword
@@ -2457,6 +2497,21 @@ _git_reset ()
 	__git_complete_refs
 }
 
+_git_restore ()
+{
+	case "$cur" in
+	--conflict=*)
+		__gitcomp "diff3 merge" "" "${cur##--conflict=}"
+		;;
+	--source=*)
+		__git_complete_refs --cur="${cur##--source=}"
+		;;
+	--*)
+		__gitcomp_builtin restore
+		;;
+	esac
+}
+
 __git_revert_inprogress_options="--continue --quit --abort"
 
 _git_revert ()
diff --git a/decorate.c b/decorate.c
index de31331fa4..a605b1b5f4 100644
--- a/decorate.c
+++ b/decorate.c
@@ -8,7 +8,7 @@
 
 static unsigned int hash_obj(const struct object *obj, unsigned int n)
 {
-	return sha1hash(obj->oid.hash) % n;
+	return oidhash(&obj->oid) % n;
 }
 
 static void *insert_decoration(struct decoration *n, const struct object *base, void *decoration)
diff --git a/delta-islands.c b/delta-islands.c
index 2186bd0738..09dbd3cf72 100644
--- a/delta-islands.c
+++ b/delta-islands.c
@@ -22,7 +22,7 @@
 
 KHASH_INIT(str, const char *, void *, 1, kh_str_hash_func, kh_str_hash_equal)
 
-static khash_sha1 *island_marks;
+static kh_oid_map_t *island_marks;
 static unsigned island_counter;
 static unsigned island_counter_core;
 
@@ -105,7 +105,7 @@ int in_same_island(const struct object_id *trg_oid, const struct object_id *src_
 	 * If we don't have a bitmap for the target, we can delta it
 	 * against anything -- it's not an important object
 	 */
-	trg_pos = kh_get_sha1(island_marks, trg_oid->hash);
+	trg_pos = kh_get_oid_map(island_marks, *trg_oid);
 	if (trg_pos >= kh_end(island_marks))
 		return 1;
 
@@ -113,7 +113,7 @@ int in_same_island(const struct object_id *trg_oid, const struct object_id *src_
 	 * if the source (our delta base) doesn't have a bitmap,
 	 * we don't want to base any deltas on it!
 	 */
-	src_pos = kh_get_sha1(island_marks, src_oid->hash);
+	src_pos = kh_get_oid_map(island_marks, *src_oid);
 	if (src_pos >= kh_end(island_marks))
 		return 0;
 
@@ -129,11 +129,11 @@ int island_delta_cmp(const struct object_id *a, const struct object_id *b)
 	if (!island_marks)
 		return 0;
 
-	a_pos = kh_get_sha1(island_marks, a->hash);
+	a_pos = kh_get_oid_map(island_marks, *a);
 	if (a_pos < kh_end(island_marks))
 		a_bitmap = kh_value(island_marks, a_pos);
 
-	b_pos = kh_get_sha1(island_marks, b->hash);
+	b_pos = kh_get_oid_map(island_marks, *b);
 	if (b_pos < kh_end(island_marks))
 		b_bitmap = kh_value(island_marks, b_pos);
 
@@ -154,7 +154,7 @@ static struct island_bitmap *create_or_get_island_marks(struct object *obj)
 	khiter_t pos;
 	int hash_ret;
 
-	pos = kh_put_sha1(island_marks, obj->oid.hash, &hash_ret);
+	pos = kh_put_oid_map(island_marks, obj->oid, &hash_ret);
 	if (hash_ret)
 		kh_value(island_marks, pos) = island_bitmap_new(NULL);
 
@@ -167,7 +167,7 @@ static void set_island_marks(struct object *obj, struct island_bitmap *marks)
 	khiter_t pos;
 	int hash_ret;
 
-	pos = kh_put_sha1(island_marks, obj->oid.hash, &hash_ret);
+	pos = kh_put_oid_map(island_marks, obj->oid, &hash_ret);
 	if (hash_ret) {
 		/*
 		 * We don't have one yet; make a copy-on-write of the
@@ -279,7 +279,7 @@ void resolve_tree_islands(struct repository *r,
 		struct name_entry entry;
 		khiter_t pos;
 
-		pos = kh_get_sha1(island_marks, ent->idx.oid.hash);
+		pos = kh_get_oid_map(island_marks, ent->idx.oid);
 		if (pos >= kh_end(island_marks))
 			continue;
 
@@ -296,7 +296,7 @@ void resolve_tree_islands(struct repository *r,
 			if (S_ISGITLINK(entry.mode))
 				continue;
 
-			obj = lookup_object(r, entry.oid.hash);
+			obj = lookup_object(r, &entry.oid);
 			if (!obj)
 				continue;
 
@@ -454,21 +454,22 @@ static void deduplicate_islands(struct repository *r)
 	free(list);
 }
 
-void load_delta_islands(struct repository *r)
+void load_delta_islands(struct repository *r, int progress)
 {
-	island_marks = kh_init_sha1();
+	island_marks = kh_init_oid_map();
 	remote_islands = kh_init_str();
 
 	git_config(island_config_callback, NULL);
 	for_each_ref(find_island_for_ref, NULL);
 	deduplicate_islands(r);
 
-	fprintf(stderr, _("Marked %d islands, done.\n"), island_counter);
+	if (progress)
+		fprintf(stderr, _("Marked %d islands, done.\n"), island_counter);
 }
 
 void propagate_island_marks(struct commit *commit)
 {
-	khiter_t pos = kh_get_sha1(island_marks, commit->object.oid.hash);
+	khiter_t pos = kh_get_oid_map(island_marks, commit->object.oid);
 
 	if (pos < kh_end(island_marks)) {
 		struct commit_list *p;
@@ -490,7 +491,7 @@ int compute_pack_layers(struct packing_data *to_pack)
 
 	for (i = 0; i < to_pack->nr_objects; ++i) {
 		struct object_entry *entry = &to_pack->objects[i];
-		khiter_t pos = kh_get_sha1(island_marks, entry->idx.oid.hash);
+		khiter_t pos = kh_get_oid_map(island_marks, entry->idx.oid);
 
 		oe_set_layer(to_pack, entry, 1);
 
diff --git a/delta-islands.h b/delta-islands.h
index 3ac8045d8c..eb0f952629 100644
--- a/delta-islands.h
+++ b/delta-islands.h
@@ -11,7 +11,7 @@ int in_same_island(const struct object_id *, const struct object_id *);
 void resolve_tree_islands(struct repository *r,
 			  int progress,
 			  struct packing_data *to_pack);
-void load_delta_islands(struct repository *r);
+void load_delta_islands(struct repository *r, int progress);
 void propagate_island_marks(struct commit *commit);
 int compute_pack_layers(struct packing_data *to_pack);
 
diff --git a/diffcore-rename.c b/diffcore-rename.c
index 07bd34b631..9624864858 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -23,7 +23,7 @@ static int find_rename_dst(struct diff_filespec *two)
 	first = 0;
 	last = rename_dst_nr;
 	while (last > first) {
-		int next = (last + first) >> 1;
+		int next = first + ((last - first) >> 1);
 		struct diff_rename_dst *dst = &(rename_dst[next]);
 		int cmp = strcmp(two->path, dst->two->path);
 		if (!cmp)
@@ -83,7 +83,7 @@ static struct diff_rename_src *register_rename_src(struct diff_filepair *p)
 	first = 0;
 	last = rename_src_nr;
 	while (last > first) {
-		int next = (last + first) >> 1;
+		int next = first + ((last - first) >> 1);
 		struct diff_rename_src *src = &(rename_src[next]);
 		int cmp = strcmp(one->path, src->p->one->path);
 		if (!cmp)
@@ -266,7 +266,7 @@ static unsigned int hash_filespec(struct repository *r,
 		hash_object_file(filespec->data, filespec->size, "blob",
 				 &filespec->oid);
 	}
-	return sha1hash(filespec->oid.hash);
+	return oidhash(&filespec->oid);
 }
 
 static int find_identical_files(struct hashmap *srcs,
diff --git a/dir.c b/dir.c
index ba4a51c296..d021c908e5 100644
--- a/dir.c
+++ b/dir.c
@@ -701,7 +701,7 @@ static struct untracked_cache_dir *lookup_untracked(struct untracked_cache *uc,
 	first = 0;
 	last = dir->dirs_nr;
 	while (last > first) {
-		int cmp, next = (last + first) >> 1;
+		int cmp, next = first + ((last - first) >> 1);
 		d = dir->dirs[next];
 		cmp = strncmp(name, d->name, len);
 		if (!cmp && strlen(d->name) > len)
diff --git a/editor.c b/editor.c
index 71547674ab..f079abbf11 100644
--- a/editor.c
+++ b/editor.c
@@ -96,10 +96,10 @@ static int launch_specified_editor(const char *editor, const char *path,
 
 		if (print_waiting_for_editor && !is_terminal_dumb())
 			/*
-			 * Go back to the beginning and erase the entire line to
-			 * avoid wasting the vertical space.
+			 * Erase the entire line to avoid wasting the
+			 * vertical space.
 			 */
-			fputs("\r\033[K", stderr);
+			term_clear_line();
 	}
 
 	if (!buffer)
diff --git a/fast-import.c b/fast-import.c
index 76a7bd3699..6dfdd6801c 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -644,7 +644,7 @@ static struct tree_content *grow_tree_content(
 	struct tree_content *r = new_tree_content(t->entry_count + amt);
 	r->entry_count = t->entry_count;
 	r->delta_depth = t->delta_depth;
-	memcpy(r->entries,t->entries,t->entry_count*sizeof(t->entries[0]));
+	COPY_ARRAY(r->entries, t->entries, t->entry_count);
 	release_tree_content(t);
 	return r;
 }
diff --git a/fetch-pack.c b/fetch-pack.c
index 1c10f54e78..65be043f2a 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -286,7 +286,7 @@ static int find_common(struct fetch_negotiator *negotiator,
 		 * we cannot trust the object flags).
 		 */
 		if (!args->no_dependents &&
-		    ((o = lookup_object(the_repository, remote->hash)) != NULL) &&
+		    ((o = lookup_object(the_repository, remote)) != NULL) &&
 				(o->flags & COMPLETE)) {
 			continue;
 		}
@@ -364,7 +364,7 @@ static int find_common(struct fetch_negotiator *negotiator,
 			if (skip_prefix(reader.line, "unshallow ", &arg)) {
 				if (get_oid_hex(arg, &oid))
 					die(_("invalid unshallow line: %s"), reader.line);
-				if (!lookup_object(the_repository, oid.hash))
+				if (!lookup_object(the_repository, &oid))
 					die(_("object not found: %s"), reader.line);
 				/* make sure that it is parsed as shallow */
 				if (!parse_object(the_repository, &oid))
@@ -707,7 +707,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 	for (ref = *refs; ref; ref = ref->next) {
 		struct object *o = deref_tag(the_repository,
 					     lookup_object(the_repository,
-					     ref->old_oid.hash),
+					     &ref->old_oid),
 					     NULL, 0);
 
 		if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
@@ -734,7 +734,7 @@ static int everything_local(struct fetch_pack_args *args,
 		const struct object_id *remote = &ref->old_oid;
 		struct object *o;
 
-		o = lookup_object(the_repository, remote->hash);
+		o = lookup_object(the_repository, remote);
 		if (!o || !(o->flags & COMPLETE)) {
 			retval = 0;
 			print_verbose(args, "want %s (%s)", oid_to_hex(remote),
@@ -902,72 +902,85 @@ static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 	sort_ref_list(&ref, ref_compare_name);
 	QSORT(sought, nr_sought, cmp_ref_by_name);
 
-	if ((args->depth > 0 || is_repository_shallow(the_repository)) && !server_supports("shallow"))
+	if ((agent_feature = server_feature_value("agent", &agent_len))) {
+		agent_supported = 1;
+		if (agent_len)
+			print_verbose(args, _("Server version is %.*s"),
+				      agent_len, agent_feature);
+	}
+
+	if (server_supports("shallow"))
+		print_verbose(args, _("Server supports %s"), "shallow");
+	else if (args->depth > 0 || is_repository_shallow(the_repository))
 		die(_("Server does not support shallow clients"));
 	if (args->depth > 0 || args->deepen_since || args->deepen_not)
 		args->deepen = 1;
 	if (server_supports("multi_ack_detailed")) {
-		print_verbose(args, _("Server supports multi_ack_detailed"));
+		print_verbose(args, _("Server supports %s"), "multi_ack_detailed");
 		multi_ack = 2;
 		if (server_supports("no-done")) {
-			print_verbose(args, _("Server supports no-done"));
+			print_verbose(args, _("Server supports %s"), "no-done");
 			if (args->stateless_rpc)
 				no_done = 1;
 		}
 	}
 	else if (server_supports("multi_ack")) {
-		print_verbose(args, _("Server supports multi_ack"));
+		print_verbose(args, _("Server supports %s"), "multi_ack");
 		multi_ack = 1;
 	}
 	if (server_supports("side-band-64k")) {
-		print_verbose(args, _("Server supports side-band-64k"));
+		print_verbose(args, _("Server supports %s"), "side-band-64k");
 		use_sideband = 2;
 	}
 	else if (server_supports("side-band")) {
-		print_verbose(args, _("Server supports side-band"));
+		print_verbose(args, _("Server supports %s"), "side-band");
 		use_sideband = 1;
 	}
 	if (server_supports("allow-tip-sha1-in-want")) {
-		print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
+		print_verbose(args, _("Server supports %s"), "allow-tip-sha1-in-want");
 		allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 	}
 	if (server_supports("allow-reachable-sha1-in-want")) {
-		print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
+		print_verbose(args, _("Server supports %s"), "allow-reachable-sha1-in-want");
 		allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 	}
-	if (!server_supports("thin-pack"))
+	if (server_supports("thin-pack"))
+		print_verbose(args, _("Server supports %s"), "thin-pack");
+	else
 		args->use_thin_pack = 0;
-	if (!server_supports("no-progress"))
+	if (server_supports("no-progress"))
+		print_verbose(args, _("Server supports %s"), "no-progress");
+	else
 		args->no_progress = 0;
-	if (!server_supports("include-tag"))
+	if (server_supports("include-tag"))
+		print_verbose(args, _("Server supports %s"), "include-tag");
+	else
 		args->include_tag = 0;
 	if (server_supports("ofs-delta"))
-		print_verbose(args, _("Server supports ofs-delta"));
+		print_verbose(args, _("Server supports %s"), "ofs-delta");
 	else
 		prefer_ofs_delta = 0;
 
 	if (server_supports("filter")) {
 		server_supports_filtering = 1;
-		print_verbose(args, _("Server supports filter"));
+		print_verbose(args, _("Server supports %s"), "filter");
 	} else if (args->filter_options.choice) {
 		warning("filtering not recognized by server, ignoring");
 	}
 
-	if ((agent_feature = server_feature_value("agent", &agent_len))) {
-		agent_supported = 1;
-		if (agent_len)
-			print_verbose(args, _("Server version is %.*s"),
-				      agent_len, agent_feature);
-	}
-	if (server_supports("deepen-since"))
+	if (server_supports("deepen-since")) {
+		print_verbose(args, _("Server supports %s"), "deepen-since");
 		deepen_since_ok = 1;
-	else if (args->deepen_since)
+	} else if (args->deepen_since)
 		die(_("Server does not support --shallow-since"));
-	if (server_supports("deepen-not"))
+	if (server_supports("deepen-not")) {
+		print_verbose(args, _("Server supports %s"), "deepen-not");
 		deepen_not_ok = 1;
-	else if (args->deepen_not)
+	} else if (args->deepen_not)
 		die(_("Server does not support --shallow-exclude"));
-	if (!server_supports("deepen-relative") && args->deepen_relative)
+	if (server_supports("deepen-relative"))
+		print_verbose(args, _("Server supports %s"), "deepen-relative");
+	else if (args->deepen_relative)
 		die(_("Server does not support --deepen"));
 
 	if (!args->no_dependents) {
@@ -1048,7 +1061,7 @@ static void add_wants(int no_dependents, const struct ref *wants, struct strbuf
 		 * we cannot trust the object flags).
 		 */
 		if (!no_dependents &&
-		    ((o = lookup_object(the_repository, remote->hash)) != NULL) &&
+		    ((o = lookup_object(the_repository, remote)) != NULL) &&
 		    (o->flags & COMPLETE)) {
 			continue;
 		}
@@ -1275,7 +1288,7 @@ static void receive_shallow_info(struct fetch_pack_args *args,
 		if (skip_prefix(reader->line, "unshallow ", &arg)) {
 			if (get_oid_hex(arg, &oid))
 				die(_("invalid unshallow line: %s"), reader->line);
-			if (!lookup_object(the_repository, oid.hash))
+			if (!lookup_object(the_repository, &oid))
 				die(_("object not found: %s"), reader->line);
 			/* make sure that it is parsed as shallow */
 			if (!parse_object(the_repository, &oid))
diff --git a/fsck.c b/fsck.c
index 4703f55561..117c4a978f 100644
--- a/fsck.c
+++ b/fsck.c
@@ -1092,7 +1092,7 @@ int fsck_finish(struct fsck_options *options)
 
 		blob = lookup_blob(the_repository, oid);
 		if (!blob) {
-			struct object *obj = lookup_unknown_object(oid->hash);
+			struct object *obj = lookup_unknown_object(oid);
 			ret |= report(options, obj,
 				      FSCK_MSG_GITMODULES_BLOB,
 				      "non-blob found at .gitmodules");
diff --git a/fsmonitor.c b/fsmonitor.c
index 1dee0aded1..231e83a94d 100644
--- a/fsmonitor.c
+++ b/fsmonitor.c
@@ -56,7 +56,7 @@ int read_fsmonitor_extension(struct index_state *istate, const void *data,
 
 void fill_fsmonitor_bitmap(struct index_state *istate)
 {
-	int i;
+	unsigned int i;
 	istate->fsmonitor_dirty = ewah_new();
 	for (i = 0; i < istate->cache_nr; i++)
 		if (!(istate->cache[i]->ce_flags & CE_FSMONITOR_VALID))
@@ -134,7 +134,7 @@ void refresh_fsmonitor(struct index_state *istate)
 	size_t bol; /* beginning of line */
 	uint64_t last_update;
 	char *buf;
-	int i;
+	unsigned int i;
 
 	if (!core_fsmonitor || istate->fsmonitor_has_run_once)
 		return;
@@ -192,7 +192,7 @@ void refresh_fsmonitor(struct index_state *istate)
 
 void add_fsmonitor(struct index_state *istate)
 {
-	int i;
+	unsigned int i;
 
 	if (!istate->fsmonitor_last_update) {
 		trace_printf_key(&trace_fsmonitor, "add fsmonitor");
@@ -225,7 +225,7 @@ void remove_fsmonitor(struct index_state *istate)
 
 void tweak_fsmonitor(struct index_state *istate)
 {
-	int i;
+	unsigned int i;
 	int fsmonitor_enabled = git_config_get_fsmonitor();
 
 	if (istate->fsmonitor_dirty) {
diff --git a/git-add--interactive.perl b/git-add--interactive.perl
index 20eb81cc92..c20ae9e210 100755
--- a/git-add--interactive.perl
+++ b/git-add--interactive.perl
@@ -149,6 +149,20 @@ sub colored {
 		FILTER => undef,
 		IS_REVERSE => 0,
 	},
+	'worktree_head' => {
+		DIFF => 'diff-index -p',
+		APPLY => sub { apply_patch 'apply -R', @_ },
+		APPLY_CHECK => 'apply -R',
+		FILTER => undef,
+		IS_REVERSE => 1,
+	},
+	'worktree_nothead' => {
+		DIFF => 'diff-index -R -p',
+		APPLY => sub { apply_patch 'apply', @_ },
+		APPLY_CHECK => 'apply',
+		FILTER => undef,
+		IS_REVERSE => 0,
+	},
 );
 
 $patch_mode = 'stage';
@@ -972,7 +986,11 @@ sub coalesce_overlapping_hunks {
 			next;
 		}
 		if ($ofs_delta) {
-			$n_ofs += $ofs_delta;
+			if ($patch_mode_flavour{IS_REVERSE}) {
+				$o_ofs -= $ofs_delta;
+			} else {
+				$n_ofs += $ofs_delta;
+			}
 			$_->{TEXT}->[0] = format_hunk_header($o_ofs, $o_cnt,
 							     $n_ofs, $n_cnt);
 		}
@@ -1049,6 +1067,12 @@ sub color_diff {
 marked for discarding."),
 	checkout_nothead => N__(
 "If the patch applies cleanly, the edited hunk will immediately be
+marked for applying."),
+	worktree_head => N__(
+"If the patch applies cleanly, the edited hunk will immediately be
+marked for discarding."),
+	worktree_nothead => N__(
+"If the patch applies cleanly, the edited hunk will immediately be
 marked for applying."),
 );
 
@@ -1259,6 +1283,18 @@ sub edit_hunk_loop {
 n - do not apply this hunk to index and worktree
 q - quit; do not apply this hunk or any of the remaining ones
 a - apply this hunk and all later hunks in the file
+d - do not apply this hunk or any of the later hunks in the file"),
+	worktree_head => N__(
+"y - discard this hunk from worktree
+n - do not discard this hunk from worktree
+q - quit; do not discard this hunk or any of the remaining ones
+a - discard this hunk and all later hunks in the file
+d - do not discard this hunk or any of the later hunks in the file"),
+	worktree_nothead => N__(
+"y - apply this hunk to worktree
+n - do not apply this hunk to worktree
+q - quit; do not apply this hunk or any of the remaining ones
+a - apply this hunk and all later hunks in the file
 d - do not apply this hunk or any of the later hunks in the file"),
 );
 
@@ -1421,6 +1457,16 @@ sub display_hunks {
 		deletion => N__("Apply deletion to index and worktree [y,n,q,a,d%s,?]? "),
 		hunk => N__("Apply this hunk to index and worktree [y,n,q,a,d%s,?]? "),
 	},
+	worktree_head => {
+		mode => N__("Discard mode change from worktree [y,n,q,a,d%s,?]? "),
+		deletion => N__("Discard deletion from worktree [y,n,q,a,d%s,?]? "),
+		hunk => N__("Discard this hunk from worktree [y,n,q,a,d%s,?]? "),
+	},
+	worktree_nothead => {
+		mode => N__("Apply mode change to worktree [y,n,q,a,d%s,?]? "),
+		deletion => N__("Apply deletion to worktree [y,n,q,a,d%s,?]? "),
+		hunk => N__("Apply this hunk to worktree [y,n,q,a,d%s,?]? "),
+	},
 );
 
 sub patch_update_file {
@@ -1756,6 +1802,16 @@ sub process_args {
 						       'checkout_head' : 'checkout_nothead');
 					$arg = shift @ARGV or die __("missing --");
 				}
+			} elsif ($1 eq 'worktree') {
+				$arg = shift @ARGV or die __("missing --");
+				if ($arg eq '--') {
+					$patch_mode = 'checkout_index';
+				} else {
+					$patch_mode_revision = $arg;
+					$patch_mode = ($arg eq 'HEAD' ?
+						       'worktree_head' : 'worktree_nothead');
+					$arg = shift @ARGV or die __("missing --");
+				}
 			} elsif ($1 eq 'stage' or $1 eq 'stash') {
 				$patch_mode = $1;
 				$arg = shift @ARGV or die __("missing --");
diff --git a/git-compat-util.h b/git-compat-util.h
index cc0e7e9733..83be89de0a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1,6 +1,15 @@
 #ifndef GIT_COMPAT_UTIL_H
 #define GIT_COMPAT_UTIL_H
 
+#ifdef USE_MSVC_CRTDBG
+/*
+ * For these to work they must appear very early in each
+ * file -- before most of the standard header files.
+ */
+#include <stdlib.h>
+#include <crtdbg.h>
+#endif
+
 #define _FILE_OFFSET_BITS 64
 
 
diff --git a/git-mergetool.sh b/git-mergetool.sh
index 88fa6a914a..e3f6d543fb 100755
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -228,9 +228,8 @@ stage_submodule () {
 }
 
 checkout_staged_file () {
-	tmpfile=$(expr \
-		"$(git checkout-index --temp --stage="$1" "$2" 2>/dev/null)" \
-		: '\([^	]*\)	')
+	tmpfile="$(git checkout-index --temp --stage="$1" "$2" 2>/dev/null)" &&
+	tmpfile=${tmpfile%%'	'*}
 
 	if test $? -eq 0 && test -n "$tmpfile"
 	then
@@ -255,13 +254,16 @@ merge_file () {
 		return 1
 	fi
 
-	if BASE=$(expr "$MERGED" : '\(.*\)\.[^/]*$')
-	then
-		ext=$(expr "$MERGED" : '.*\(\.[^/]*\)$')
-	else
+	# extract file extension from the last path component
+	case "${MERGED##*/}" in
+	*.*)
+		ext=.${MERGED##*.}
+		BASE=${MERGED%"$ext"}
+		;;
+	*)
 		BASE=$MERGED
 		ext=
-	fi
+	esac
 
 	mergetool_tmpdir_init
 
@@ -277,15 +279,30 @@ merge_file () {
 	REMOTE="$MERGETOOL_TMPDIR/${BASE}_REMOTE_$$$ext"
 	BASE="$MERGETOOL_TMPDIR/${BASE}_BASE_$$$ext"
 
-	base_mode=$(git ls-files -u -- "$MERGED" | awk '{if ($3==1) print $1;}')
-	local_mode=$(git ls-files -u -- "$MERGED" | awk '{if ($3==2) print $1;}')
-	remote_mode=$(git ls-files -u -- "$MERGED" | awk '{if ($3==3) print $1;}')
+	base_mode= local_mode= remote_mode=
+
+	# here, $IFS is just a LF
+	for line in $f
+	do
+		mode=${line%% *}		# 1st word
+		sha1=${line#"$mode "}
+		sha1=${sha1%% *}		# 2nd word
+		case "${line#$mode $sha1 }" in	# remainder
+		'1	'*)
+			base_mode=$mode
+			;;
+		'2	'*)
+			local_mode=$mode local_sha1=$sha1
+			;;
+		'3	'*)
+			remote_mode=$mode remote_sha1=$sha1
+			;;
+		esac
+	done
 
 	if is_submodule "$local_mode" || is_submodule "$remote_mode"
 	then
 		echo "Submodule merge conflict for '$MERGED':"
-		local_sha1=$(git ls-files -u -- "$MERGED" | awk '{if ($3==2) print $2;}')
-		remote_sha1=$(git ls-files -u -- "$MERGED" | awk '{if ($3==3) print $2;}')
 		describe_file "$local_mode" "local" "$local_sha1"
 		describe_file "$remote_mode" "remote" "$remote_sha1"
 		resolve_submodule_merge
@@ -406,7 +423,7 @@ main () {
 		-t|--tool*)
 			case "$#,$1" in
 			*,*=*)
-				merge_tool=$(expr "z$1" : 'z-[^=]*=\(.*\)')
+				merge_tool=${1#*=}
 				;;
 			1,*)
 				usage ;;
diff --git a/git-p4.py b/git-p4.py
index c71a6832e2..3991e7d1a7 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -1316,7 +1316,7 @@ def __init__(self):
         self.needsGit = True
         self.verbose = False
 
-    # This is required for the "append" cloneExclude action
+    # This is required for the "append" update_shelve action
     def ensure_value(self, attr, value):
         if not hasattr(self, attr) or getattr(self, attr) is None:
             setattr(self, attr, value)
@@ -2530,6 +2530,11 @@ def map_in_client(self, depot_path):
         die( "Error: %s is not found in client spec path" % depot_path )
         return ""
 
+def cloneExcludeCallback(option, opt_str, value, parser):
+    # prepend "/" because the first "/" was consumed as part of the option itself.
+    # ("-//depot/A/..." becomes "/depot/A/..." after option parsing)
+    parser.values.cloneExclude += ["/" + re.sub(r"\.\.\.$", "", value)]
+
 class P4Sync(Command, P4UserMap):
 
     def __init__(self):
@@ -2553,7 +2558,7 @@ def __init__(self):
                 optparse.make_option("--use-client-spec", dest="useClientSpec", action='store_true',
                                      help="Only sync files that are included in the Perforce Client Spec"),
                 optparse.make_option("-/", dest="cloneExclude",
-                                     action="append", type="string",
+                                     action="callback", callback=cloneExcludeCallback, type="string",
                                      help="exclude depot path"),
         ]
         self.description = """Imports from Perforce into a git repository.\n
@@ -2618,20 +2623,25 @@ def checkpoint(self):
         if self.verbose:
             print("checkpoint finished: " + out)
 
+    def isPathWanted(self, path):
+        for p in self.cloneExclude:
+            if p.endswith("/"):
+                if p4PathStartsWith(path, p):
+                    return False
+            # "-//depot/file1" without a trailing "/" should only exclude "file1", but not "file111" or "file1_dir/file2"
+            elif path.lower() == p.lower():
+                return False
+        for p in self.depotPaths:
+            if p4PathStartsWith(path, p):
+                return True
+        return False
+
     def extractFilesFromCommit(self, commit, shelved=False, shelved_cl = 0):
-        self.cloneExclude = [re.sub(r"\.\.\.$", "", path)
-                             for path in self.cloneExclude]
         files = []
         fnum = 0
         while "depotFile%s" % fnum in commit:
             path =  commit["depotFile%s" % fnum]
-
-            if [p for p in self.cloneExclude
-                if p4PathStartsWith(path, p)]:
-                found = False
-            else:
-                found = [p for p in self.depotPaths
-                         if p4PathStartsWith(path, p)]
+            found = self.isPathWanted(path)
             if not found:
                 fnum = fnum + 1
                 continue
@@ -2668,7 +2678,7 @@ def stripRepoPath(self, path, prefixes):
             path = self.clientSpecDirs.map_in_client(path)
             if self.detectBranches:
                 for b in self.knownBranches:
-                    if path.startswith(b + "/"):
+                    if p4PathStartsWith(path, b + "/"):
                         path = path[len(b)+1:]
 
         elif self.keepRepoPath:
@@ -2700,8 +2710,7 @@ def splitFilesIntoBranches(self, commit):
         fnum = 0
         while "depotFile%s" % fnum in commit:
             path =  commit["depotFile%s" % fnum]
-            found = [p for p in self.depotPaths
-                     if p4PathStartsWith(path, p)]
+            found = self.isPathWanted(path)
             if not found:
                 fnum = fnum + 1
                 continue
@@ -2723,7 +2732,7 @@ def splitFilesIntoBranches(self, commit):
             for branch in self.knownBranches.keys():
                 # add a trailing slash so that a commit into qt/4.2foo
                 # doesn't end up in qt/4.2, e.g.
-                if relPath.startswith(branch + "/"):
+                if p4PathStartsWith(relPath, branch + "/"):
                     if branch not in branches:
                         branches[branch] = []
                     branches[branch].append(file)
@@ -3325,7 +3334,9 @@ def gitCommitByP4Change(self, ref, change):
             if currentChange < change:
                 earliestCommit = "^%s" % next
             else:
-                latestCommit = "%s" % next
+                if next == latestCommit:
+                    die("Infinite loop while looking in ref %s for change %s. Check your branch mappings" % (ref, change))
+                latestCommit = "%s^@" % next
 
         return ""
 
@@ -3888,7 +3899,6 @@ def run(self, args):
             self.cloneDestination = depotPaths[-1]
             depotPaths = depotPaths[:-1]
 
-        self.cloneExclude = ["/"+p for p in self.cloneExclude]
         for p in depotPaths:
             if not p.startswith("//"):
                 sys.stderr.write('Depot paths must start with "//": %s\n' % p)
diff --git a/git.c b/git.c
index c2eec470c9..f4c0478f32 100644
--- a/git.c
+++ b/git.c
@@ -566,6 +566,7 @@ static struct cmd_struct commands[] = {
 	{ "replace", cmd_replace, RUN_SETUP },
 	{ "rerere", cmd_rerere, RUN_SETUP },
 	{ "reset", cmd_reset, RUN_SETUP },
+	{ "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
 	{ "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 	{ "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 	{ "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
@@ -586,6 +587,7 @@ static struct cmd_struct commands[] = {
 	{ "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 	{ "stripspace", cmd_stripspace },
 	{ "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
+	{ "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
 	{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 	{ "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 	{ "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
diff --git a/hash.h b/hash.h
index 661c9f2281..52a4f1a3f4 100644
--- a/hash.h
+++ b/hash.h
@@ -139,4 +139,28 @@ static inline int hash_algo_by_ptr(const struct git_hash_algo *p)
 	return p - hash_algos;
 }
 
+/* The length in bytes and in hex digits of an object name (SHA-1 value). */
+#define GIT_SHA1_RAWSZ 20
+#define GIT_SHA1_HEXSZ (2 * GIT_SHA1_RAWSZ)
+/* The block size of SHA-1. */
+#define GIT_SHA1_BLKSZ 64
+
+/* The length in bytes and in hex digits of an object name (SHA-256 value). */
+#define GIT_SHA256_RAWSZ 32
+#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
+/* The block size of SHA-256. */
+#define GIT_SHA256_BLKSZ 64
+
+/* The length in byte and in hex digits of the largest possible hash value. */
+#define GIT_MAX_RAWSZ GIT_SHA256_RAWSZ
+#define GIT_MAX_HEXSZ GIT_SHA256_HEXSZ
+/* The largest possible block size for any supported hash. */
+#define GIT_MAX_BLKSZ GIT_SHA256_BLKSZ
+
+struct object_id {
+	unsigned char hash[GIT_MAX_RAWSZ];
+};
+
+#define the_hash_algo the_repository->hash_algo
+
 #endif
diff --git a/hashmap.h b/hashmap.h
index f95593b6cf..8424911566 100644
--- a/hashmap.h
+++ b/hashmap.h
@@ -1,6 +1,8 @@
 #ifndef HASHMAP_H
 #define HASHMAP_H
 
+#include "hash.h"
+
 /*
  * Generic implementation of hash-based key-value mappings.
  *
@@ -118,14 +120,14 @@ unsigned int memihash_cont(unsigned int hash_seed, const void *buf, size_t len);
  * the results will be different on big-endian and little-endian
  * platforms, so they should not be stored or transferred over the net.
  */
-static inline unsigned int sha1hash(const unsigned char *sha1)
+static inline unsigned int oidhash(const struct object_id *oid)
 {
 	/*
-	 * Equivalent to 'return *(unsigned int *)sha1;', but safe on
+	 * Equivalent to 'return *(unsigned int *)oid->hash;', but safe on
 	 * platforms that don't support unaligned reads.
 	 */
 	unsigned int hash;
-	memcpy(&hash, sha1, sizeof(hash));
+	memcpy(&hash, oid->hash, sizeof(hash));
 	return hash;
 }
 
diff --git a/http-push.c b/http-push.c
index e36561a6db..0353f9f514 100644
--- a/http-push.c
+++ b/http-push.c
@@ -723,7 +723,7 @@ static void one_remote_object(const struct object_id *oid)
 {
 	struct object *obj;
 
-	obj = lookup_object(the_repository, oid->hash);
+	obj = lookup_object(the_repository, oid);
 	if (!obj)
 		obj = parse_object(the_repository, oid);
 
@@ -1432,7 +1432,7 @@ static void one_remote_ref(const char *refname)
 	 * may be required for updating server info later.
 	 */
 	if (repo->can_update_info_refs && !has_object_file(&ref->old_oid)) {
-		obj = lookup_unknown_object(ref->old_oid.hash);
+		obj = lookup_unknown_object(&ref->old_oid);
 		fprintf(stderr,	"  fetch %s for %s\n",
 			oid_to_hex(&ref->old_oid), refname);
 		add_fetch_request(obj);
diff --git a/khash.h b/khash.h
index af747a683f..21c2095216 100644
--- a/khash.h
+++ b/khash.h
@@ -324,30 +324,20 @@ static const double __ac_HASH_UPPER = 0.77;
 		code;												\
 	} }
 
-#define __kh_oid_cmp(a, b) (hashcmp(a, b) == 0)
-
-KHASH_INIT(sha1, const unsigned char *, void *, 1, sha1hash, __kh_oid_cmp)
-typedef kh_sha1_t khash_sha1;
-
-KHASH_INIT(sha1_pos, const unsigned char *, int, 1, sha1hash, __kh_oid_cmp)
-typedef kh_sha1_pos_t khash_sha1_pos;
-
-static inline unsigned int oid_hash(struct object_id oid)
+static inline unsigned int oidhash_by_value(struct object_id oid)
 {
-	return sha1hash(oid.hash);
+	return oidhash(&oid);
 }
 
-static inline int oid_equal(struct object_id a, struct object_id b)
+static inline int oideq_by_value(struct object_id a, struct object_id b)
 {
 	return oideq(&a, &b);
 }
 
-KHASH_INIT(oid, struct object_id, int, 0, oid_hash, oid_equal)
+KHASH_INIT(oid_set, struct object_id, int, 0, oidhash_by_value, oideq_by_value)
 
-KHASH_INIT(oid_map, struct object_id, void *, 1, oid_hash, oid_equal)
-typedef kh_oid_t khash_oid_map;
+KHASH_INIT(oid_map, struct object_id, void *, 1, oidhash_by_value, oideq_by_value)
 
-KHASH_INIT(oid_pos, struct object_id, int, 1, oid_hash, oid_equal)
-typedef kh_oid_pos_t khash_oid_pos;
+KHASH_INIT(oid_pos, struct object_id, int, 1, oidhash_by_value, oideq_by_value)
 
 #endif /* __AC_KHASH_H */
diff --git a/kwset.c b/kwset.c
index 4fb6455aca..fc439e0667 100644
--- a/kwset.c
+++ b/kwset.c
@@ -38,7 +38,13 @@
 #include "compat/obstack.h"
 
 #define NCHAR (UCHAR_MAX + 1)
-#define obstack_chunk_alloc xmalloc
+/* adapter for `xmalloc()`, which takes `size_t`, not `long` */
+static void *obstack_chunk_alloc(long size)
+{
+	if (size < 0)
+		BUG("Cannot allocate a negative amount: %ld", size);
+	return xmalloc(size);
+}
 #define obstack_chunk_free free
 
 #define U(c) ((unsigned char) (c))
@@ -475,7 +481,7 @@ kwsprep (kwset_t kws)
 	for (i = 0; i < NCHAR; ++i)
 	  kwset->next[i] = next[U(trans[i])];
       else
-	memcpy(kwset->next, next, NCHAR * sizeof(struct trie *));
+	COPY_ARRAY(kwset->next, next, NCHAR);
     }
 
   /* Fix things up for any translation table. */
diff --git a/list-objects-filter-options.c b/list-objects-filter-options.c
index a15d0f7829..1cb20c659c 100644
--- a/list-objects-filter-options.c
+++ b/list-objects-filter-options.c
@@ -91,7 +91,7 @@ static int gently_parse_list_objects_filter(
 	 */
 
 	if (errbuf)
-		strbuf_addf(errbuf, "invalid filter-spec '%s'", arg);
+		strbuf_addf(errbuf, _("invalid filter-spec '%s'"), arg);
 
 	memset(filter_options, 0, sizeof(*filter_options));
 	return 1;
diff --git a/list-objects-filter.c b/list-objects-filter.c
index 53f90442c5..36e1f774bc 100644
--- a/list-objects-filter.c
+++ b/list-objects-filter.c
@@ -356,13 +356,13 @@ static enum list_objects_filter_result filter_sparse(
 					    filename, &dtype, &filter_data->el,
 					    r->index);
 		if (val < 0)
-			val = filter_data->array_frame[filter_data->nr].defval;
+			val = filter_data->array_frame[filter_data->nr - 1].defval;
 
 		ALLOC_GROW(filter_data->array_frame, filter_data->nr + 1,
 			   filter_data->alloc);
-		filter_data->nr++;
 		filter_data->array_frame[filter_data->nr].defval = val;
 		filter_data->array_frame[filter_data->nr].child_prov_omit = 0;
+		filter_data->nr++;
 
 		/*
 		 * A directory with this tree OID may appear in multiple
@@ -387,16 +387,15 @@ static enum list_objects_filter_result filter_sparse(
 
 	case LOFS_END_TREE:
 		assert(obj->type == OBJ_TREE);
-		assert(filter_data->nr > 0);
+		assert(filter_data->nr > 1);
 
-		frame = &filter_data->array_frame[filter_data->nr];
-		filter_data->nr--;
+		frame = &filter_data->array_frame[--filter_data->nr];
 
 		/*
 		 * Tell our parent directory if any of our children were
 		 * provisionally omitted.
 		 */
-		filter_data->array_frame[filter_data->nr].child_prov_omit |=
+		filter_data->array_frame[filter_data->nr - 1].child_prov_omit |=
 			frame->child_prov_omit;
 
 		/*
@@ -412,7 +411,7 @@ static enum list_objects_filter_result filter_sparse(
 		assert(obj->type == OBJ_BLOB);
 		assert((obj->flags & SEEN) == 0);
 
-		frame = &filter_data->array_frame[filter_data->nr];
+		frame = &filter_data->array_frame[filter_data->nr - 1];
 
 		dtype = DT_REG;
 		val = is_excluded_from_list(pathname, strlen(pathname),
@@ -453,7 +452,7 @@ static enum list_objects_filter_result filter_sparse(
 static void filter_sparse_free(void *filter_data)
 {
 	struct filter_sparse_data *d = filter_data;
-	/* TODO free contents of 'd' */
+	free(d->array_frame);
 	free(d);
 }
 
@@ -472,6 +471,7 @@ static void *filter_sparse_oid__init(
 	ALLOC_GROW(d->array_frame, d->nr + 1, d->alloc);
 	d->array_frame[d->nr].defval = 0; /* default to include */
 	d->array_frame[d->nr].child_prov_omit = 0;
+	d->nr++;
 
 	*filter_fn = filter_sparse;
 	*filter_free_fn = filter_sparse_free;
diff --git a/name-hash.c b/name-hash.c
index b4861bc7b0..695908609f 100644
--- a/name-hash.c
+++ b/name-hash.c
@@ -345,8 +345,9 @@ static int handle_range_dir(
 	else {
 		int begin = k_start;
 		int end = k_end;
+		assert(begin >= 0);
 		while (begin < end) {
-			int mid = (begin + end) >> 1;
+			int mid = begin + ((end - begin) >> 1);
 			int cmp = strncmp(istate->cache[mid]->name, prefix->buf, prefix->len);
 			if (cmp == 0) /* mid has same prefix; look in second part */
 				begin = mid + 1;
diff --git a/object.c b/object.c
index e81d47a79c..07bdd5b26e 100644
--- a/object.c
+++ b/object.c
@@ -59,9 +59,9 @@ int type_from_string_gently(const char *str, ssize_t len, int gentle)
  * the specified sha1.  n must be a power of 2.  Please note that the
  * return value is *not* consistent across computer architectures.
  */
-static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
+static unsigned int hash_obj(const struct object_id *oid, unsigned int n)
 {
-	return sha1hash(sha1) & (n - 1);
+	return oidhash(oid) & (n - 1);
 }
 
 /*
@@ -71,7 +71,7 @@ static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
  */
 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
 {
-	unsigned int j = hash_obj(obj->oid.hash, size);
+	unsigned int j = hash_obj(&obj->oid, size);
 
 	while (hash[j]) {
 		j++;
@@ -85,7 +85,7 @@ static void insert_obj_hash(struct object *obj, struct object **hash, unsigned i
  * Look up the record for the given sha1 in the hash map stored in
  * obj_hash.  Return NULL if it was not found.
  */
-struct object *lookup_object(struct repository *r, const unsigned char *sha1)
+struct object *lookup_object(struct repository *r, const struct object_id *oid)
 {
 	unsigned int i, first;
 	struct object *obj;
@@ -93,9 +93,9 @@ struct object *lookup_object(struct repository *r, const unsigned char *sha1)
 	if (!r->parsed_objects->obj_hash)
 		return NULL;
 
-	first = i = hash_obj(sha1, r->parsed_objects->obj_hash_size);
+	first = i = hash_obj(oid, r->parsed_objects->obj_hash_size);
 	while ((obj = r->parsed_objects->obj_hash[i]) != NULL) {
-		if (hasheq(sha1, obj->oid.hash))
+		if (oideq(oid, &obj->oid))
 			break;
 		i++;
 		if (i == r->parsed_objects->obj_hash_size)
@@ -141,13 +141,13 @@ static void grow_object_hash(struct repository *r)
 	r->parsed_objects->obj_hash_size = new_hash_size;
 }
 
-void *create_object(struct repository *r, const unsigned char *sha1, void *o)
+void *create_object(struct repository *r, const struct object_id *oid, void *o)
 {
 	struct object *obj = o;
 
 	obj->parsed = 0;
 	obj->flags = 0;
-	hashcpy(obj->oid.hash, sha1);
+	oidcpy(&obj->oid, oid);
 
 	if (r->parsed_objects->obj_hash_size - 1 <= r->parsed_objects->nr_objs * 2)
 		grow_object_hash(r);
@@ -178,11 +178,11 @@ void *object_as_type(struct repository *r, struct object *obj, enum object_type
 	}
 }
 
-struct object *lookup_unknown_object(const unsigned char *sha1)
+struct object *lookup_unknown_object(const struct object_id *oid)
 {
-	struct object *obj = lookup_object(the_repository, sha1);
+	struct object *obj = lookup_object(the_repository, oid);
 	if (!obj)
-		obj = create_object(the_repository, sha1,
+		obj = create_object(the_repository, oid,
 				    alloc_object_node(the_repository));
 	return obj;
 }
@@ -256,7 +256,7 @@ struct object *parse_object(struct repository *r, const struct object_id *oid)
 	void *buffer;
 	struct object *obj;
 
-	obj = lookup_object(r, oid->hash);
+	obj = lookup_object(r, oid);
 	if (obj && obj->parsed)
 		return obj;
 
@@ -268,7 +268,7 @@ struct object *parse_object(struct repository *r, const struct object_id *oid)
 			return NULL;
 		}
 		parse_blob_buffer(lookup_blob(r, oid), NULL, 0);
-		return lookup_object(r, oid->hash);
+		return lookup_object(r, oid);
 	}
 
 	buffer = repo_read_object_file(r, oid, &type, &size);
@@ -517,7 +517,7 @@ void raw_object_store_clear(struct raw_object_store *o)
 	o->loaded_alternates = 0;
 
 	INIT_LIST_HEAD(&o->packed_git_mru);
-	close_all_packs(o);
+	close_object_store(o);
 	o->packed_git = NULL;
 }
 
diff --git a/object.h b/object.h
index 4526979ccf..0120892bbd 100644
--- a/object.h
+++ b/object.h
@@ -116,9 +116,9 @@ struct object *get_indexed_object(unsigned int);
  * half-initialised objects, the caller is expected to initialize them
  * by calling parse_object() on them.
  */
-struct object *lookup_object(struct repository *r, const unsigned char *sha1);
+struct object *lookup_object(struct repository *r, const struct object_id *oid);
 
-void *create_object(struct repository *r, const unsigned char *sha1, void *obj);
+void *create_object(struct repository *r, const struct object_id *oid, void *obj);
 
 void *object_as_type(struct repository *r, struct object *obj, enum object_type type, int quiet);
 
@@ -143,7 +143,7 @@ struct object *parse_object_or_die(const struct object_id *oid, const char *name
 struct object *parse_object_buffer(struct repository *r, const struct object_id *oid, enum object_type type, unsigned long size, void *buffer, int *eaten_p);
 
 /** Returns the object, with potentially excess memory allocated. **/
-struct object *lookup_unknown_object(const unsigned  char *sha1);
+struct object *lookup_unknown_object(const struct object_id *oid);
 
 struct object_list *object_list_insert(struct object *item,
 				       struct object_list **list_p);
diff --git a/oidset.c b/oidset.c
index fe4eb921df..8bdecb13de 100644
--- a/oidset.c
+++ b/oidset.c
@@ -5,33 +5,33 @@ void oidset_init(struct oidset *set, size_t initial_size)
 {
 	memset(&set->set, 0, sizeof(set->set));
 	if (initial_size)
-		kh_resize_oid(&set->set, initial_size);
+		kh_resize_oid_set(&set->set, initial_size);
 }
 
 int oidset_contains(const struct oidset *set, const struct object_id *oid)
 {
-	khiter_t pos = kh_get_oid(&set->set, *oid);
+	khiter_t pos = kh_get_oid_set(&set->set, *oid);
 	return pos != kh_end(&set->set);
 }
 
 int oidset_insert(struct oidset *set, const struct object_id *oid)
 {
 	int added;
-	kh_put_oid(&set->set, *oid, &added);
+	kh_put_oid_set(&set->set, *oid, &added);
 	return !added;
 }
 
 int oidset_remove(struct oidset *set, const struct object_id *oid)
 {
-	khiter_t pos = kh_get_oid(&set->set, *oid);
+	khiter_t pos = kh_get_oid_set(&set->set, *oid);
 	if (pos == kh_end(&set->set))
 		return 0;
-	kh_del_oid(&set->set, pos);
+	kh_del_oid_set(&set->set, pos);
 	return 1;
 }
 
 void oidset_clear(struct oidset *set)
 {
-	kh_release_oid(&set->set);
+	kh_release_oid_set(&set->set);
 	oidset_init(set, 0);
 }
diff --git a/oidset.h b/oidset.h
index 14f18f791f..505fad578b 100644
--- a/oidset.h
+++ b/oidset.h
@@ -20,7 +20,7 @@
  * A single oidset; should be zero-initialized (or use OIDSET_INIT).
  */
 struct oidset {
-	kh_oid_t set;
+	kh_oid_set_t set;
 };
 
 #define OIDSET_INIT { { 0 } }
@@ -62,7 +62,7 @@ int oidset_remove(struct oidset *set, const struct object_id *oid);
 void oidset_clear(struct oidset *set);
 
 struct oidset_iter {
-	kh_oid_t *set;
+	kh_oid_set_t *set;
 	khiter_t iter;
 };
 
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c
index 802ed62677..fa78a460c9 100644
--- a/pack-bitmap-write.c
+++ b/pack-bitmap-write.c
@@ -28,8 +28,8 @@ struct bitmap_writer {
 	struct ewah_bitmap *blobs;
 	struct ewah_bitmap *tags;
 
-	khash_sha1 *bitmaps;
-	khash_sha1 *reused;
+	kh_oid_map_t *bitmaps;
+	kh_oid_map_t *reused;
 	struct packing_data *to_pack;
 
 	struct bitmapped_commit *selected;
@@ -142,13 +142,13 @@ static inline void reset_all_seen(void)
 	seen_objects_nr = 0;
 }
 
-static uint32_t find_object_pos(const unsigned char *hash)
+static uint32_t find_object_pos(const struct object_id *oid)
 {
-	struct object_entry *entry = packlist_find(writer.to_pack, hash, NULL);
+	struct object_entry *entry = packlist_find(writer.to_pack, oid, NULL);
 
 	if (!entry) {
 		die("Failed to write bitmap index. Packfile doesn't have full closure "
-			"(object %s is missing)", hash_to_hex(hash));
+			"(object %s is missing)", oid_to_hex(oid));
 	}
 
 	return oe_in_pack_pos(writer.to_pack, entry);
@@ -157,7 +157,7 @@ static uint32_t find_object_pos(const unsigned char *hash)
 static void show_object(struct object *object, const char *name, void *data)
 {
 	struct bitmap *base = data;
-	bitmap_set(base, find_object_pos(object->oid.hash));
+	bitmap_set(base, find_object_pos(&object->oid));
 	mark_as_seen(object);
 }
 
@@ -170,12 +170,12 @@ static int
 add_to_include_set(struct bitmap *base, struct commit *commit)
 {
 	khiter_t hash_pos;
-	uint32_t bitmap_pos = find_object_pos(commit->object.oid.hash);
+	uint32_t bitmap_pos = find_object_pos(&commit->object.oid);
 
 	if (bitmap_get(base, bitmap_pos))
 		return 0;
 
-	hash_pos = kh_get_sha1(writer.bitmaps, commit->object.oid.hash);
+	hash_pos = kh_get_oid_map(writer.bitmaps, commit->object.oid);
 	if (hash_pos < kh_end(writer.bitmaps)) {
 		struct bitmapped_commit *bc = kh_value(writer.bitmaps, hash_pos);
 		bitmap_or_ewah(base, bc->bitmap);
@@ -256,7 +256,7 @@ void bitmap_writer_build(struct packing_data *to_pack)
 	struct bitmap *base = bitmap_new();
 	struct rev_info revs;
 
-	writer.bitmaps = kh_init_sha1();
+	writer.bitmaps = kh_init_oid_map();
 	writer.to_pack = to_pack;
 
 	if (writer.show_progress)
@@ -311,7 +311,7 @@ void bitmap_writer_build(struct packing_data *to_pack)
 		if (i >= reuse_after)
 			stored->flags |= BITMAP_FLAG_REUSE;
 
-		hash_pos = kh_put_sha1(writer.bitmaps, object->oid.hash, &hash_ret);
+		hash_pos = kh_put_oid_map(writer.bitmaps, object->oid, &hash_ret);
 		if (hash_ret == 0)
 			die("Duplicate entry when writing index: %s",
 			    oid_to_hex(&object->oid));
@@ -366,7 +366,7 @@ void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack)
 	if (!(bitmap_git = prepare_bitmap_git(to_pack->repo)))
 		return;
 
-	writer.reused = kh_init_sha1();
+	writer.reused = kh_init_oid_map();
 	rebuild_existing_bitmaps(bitmap_git, to_pack, writer.reused,
 				 writer.show_progress);
 	/*
@@ -375,14 +375,14 @@ void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack)
 	 */
 }
 
-static struct ewah_bitmap *find_reused_bitmap(const unsigned char *sha1)
+static struct ewah_bitmap *find_reused_bitmap(const struct object_id *oid)
 {
 	khiter_t hash_pos;
 
 	if (!writer.reused)
 		return NULL;
 
-	hash_pos = kh_get_sha1(writer.reused, sha1);
+	hash_pos = kh_get_oid_map(writer.reused, *oid);
 	if (hash_pos >= kh_end(writer.reused))
 		return NULL;
 
@@ -422,14 +422,14 @@ void bitmap_writer_select_commits(struct commit **indexed_commits,
 
 		if (next == 0) {
 			chosen = indexed_commits[i];
-			reused_bitmap = find_reused_bitmap(chosen->object.oid.hash);
+			reused_bitmap = find_reused_bitmap(&chosen->object.oid);
 		} else {
 			chosen = indexed_commits[i + next];
 
 			for (j = 0; j <= next; ++j) {
 				struct commit *cm = indexed_commits[i + j];
 
-				reused_bitmap = find_reused_bitmap(cm->object.oid.hash);
+				reused_bitmap = find_reused_bitmap(&cm->object.oid);
 				if (reused_bitmap || (cm->object.flags & NEEDS_BITMAP) != 0) {
 					chosen = cm;
 					break;
diff --git a/pack-bitmap.c b/pack-bitmap.c
index 6069b2fe55..ed2befaac6 100644
--- a/pack-bitmap.c
+++ b/pack-bitmap.c
@@ -365,7 +365,7 @@ struct include_data {
 static inline int bitmap_position_extended(struct bitmap_index *bitmap_git,
 					   const struct object_id *oid)
 {
-	khash_oid_pos *positions = bitmap_git->ext_index.positions;
+	kh_oid_pos_t *positions = bitmap_git->ext_index.positions;
 	khiter_t pos = kh_get_oid_pos(positions, *oid);
 
 	if (pos < kh_end(positions)) {
@@ -1041,7 +1041,7 @@ static int rebuild_bitmap(uint32_t *reposition,
 
 int rebuild_existing_bitmaps(struct bitmap_index *bitmap_git,
 			     struct packing_data *mapping,
-			     khash_sha1 *reused_bitmaps,
+			     kh_oid_map_t *reused_bitmaps,
 			     int show_progress)
 {
 	uint32_t i, num_objects;
@@ -1057,13 +1057,13 @@ int rebuild_existing_bitmaps(struct bitmap_index *bitmap_git,
 	reposition = xcalloc(num_objects, sizeof(uint32_t));
 
 	for (i = 0; i < num_objects; ++i) {
-		const unsigned char *sha1;
+		struct object_id oid;
 		struct revindex_entry *entry;
 		struct object_entry *oe;
 
 		entry = &bitmap_git->pack->revindex[i];
-		sha1 = nth_packed_object_sha1(bitmap_git->pack, entry->nr);
-		oe = packlist_find(mapping, sha1, NULL);
+		nth_packed_object_oid(&oid, bitmap_git->pack, entry->nr);
+		oe = packlist_find(mapping, &oid, NULL);
 
 		if (oe)
 			reposition[i] = oe_in_pack_pos(mapping, oe) + 1;
@@ -1080,9 +1080,9 @@ int rebuild_existing_bitmaps(struct bitmap_index *bitmap_git,
 			if (!rebuild_bitmap(reposition,
 					    lookup_stored_bitmap(stored),
 					    rebuild)) {
-				hash_pos = kh_put_sha1(reused_bitmaps,
-						       stored->oid.hash,
-						       &hash_ret);
+				hash_pos = kh_put_oid_map(reused_bitmaps,
+							  stored->oid,
+							  &hash_ret);
 				kh_value(reused_bitmaps, hash_pos) =
 					bitmap_to_ewah(rebuild);
 			}
diff --git a/pack-bitmap.h b/pack-bitmap.h
index ee9792264c..00de3ec8e4 100644
--- a/pack-bitmap.h
+++ b/pack-bitmap.h
@@ -51,7 +51,7 @@ int reuse_partial_packfile_from_bitmap(struct bitmap_index *,
 				       struct packed_git **packfile,
 				       uint32_t *entries, off_t *up_to);
 int rebuild_existing_bitmaps(struct bitmap_index *, struct packing_data *mapping,
-			     khash_sha1 *reused_bitmaps, int show_progress);
+			     kh_oid_map_t *reused_bitmaps, int show_progress);
 void free_bitmap_index(struct bitmap_index *);
 
 /*
diff --git a/pack-objects.c b/pack-objects.c
index ce33b8906e..52560293b6 100644
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -6,17 +6,17 @@
 #include "config.h"
 
 static uint32_t locate_object_entry_hash(struct packing_data *pdata,
-					 const unsigned char *sha1,
+					 const struct object_id *oid,
 					 int *found)
 {
 	uint32_t i, mask = (pdata->index_size - 1);
 
-	i = sha1hash(sha1) & mask;
+	i = oidhash(oid) & mask;
 
 	while (pdata->index[i] > 0) {
 		uint32_t pos = pdata->index[i] - 1;
 
-		if (hasheq(sha1, pdata->objects[pos].idx.oid.hash)) {
+		if (oideq(oid, &pdata->objects[pos].idx.oid)) {
 			*found = 1;
 			return i;
 		}
@@ -56,7 +56,7 @@ static void rehash_objects(struct packing_data *pdata)
 	for (i = 0; i < pdata->nr_objects; i++) {
 		int found;
 		uint32_t ix = locate_object_entry_hash(pdata,
-						       entry->idx.oid.hash,
+						       &entry->idx.oid,
 						       &found);
 
 		if (found)
@@ -68,7 +68,7 @@ static void rehash_objects(struct packing_data *pdata)
 }
 
 struct object_entry *packlist_find(struct packing_data *pdata,
-				   const unsigned char *sha1,
+				   const struct object_id *oid,
 				   uint32_t *index_pos)
 {
 	uint32_t i;
@@ -77,7 +77,7 @@ struct object_entry *packlist_find(struct packing_data *pdata,
 	if (!pdata->index_size)
 		return NULL;
 
-	i = locate_object_entry_hash(pdata, sha1, &found);
+	i = locate_object_entry_hash(pdata, oid, &found);
 
 	if (index_pos)
 		*index_pos = i;
diff --git a/pack-objects.h b/pack-objects.h
index 6fde7ce27c..857d43850b 100644
--- a/pack-objects.h
+++ b/pack-objects.h
@@ -187,7 +187,7 @@ struct object_entry *packlist_alloc(struct packing_data *pdata,
 				    uint32_t index_pos);
 
 struct object_entry *packlist_find(struct packing_data *pdata,
-				   const unsigned char *sha1,
+				   const struct object_id *oid,
 				   uint32_t *index_pos);
 
 static inline uint32_t pack_name_hash(const char *name)
diff --git a/packfile.c b/packfile.c
index d786ec7312..c0d83fdfed 100644
--- a/packfile.c
+++ b/packfile.c
@@ -16,6 +16,7 @@
 #include "tree.h"
 #include "object-store.h"
 #include "midx.h"
+#include "commit-graph.h"
 
 char *odb_pack_name(struct strbuf *buf,
 		    const unsigned char *sha1,
@@ -336,7 +337,7 @@ void close_pack(struct packed_git *p)
 	close_pack_index(p);
 }
 
-void close_all_packs(struct raw_object_store *o)
+void close_object_store(struct raw_object_store *o)
 {
 	struct packed_git *p;
 
@@ -350,6 +351,8 @@ void close_all_packs(struct raw_object_store *o)
 		close_midx(o->multi_pack_index);
 		o->multi_pack_index = NULL;
 	}
+
+	close_commit_graph(o);
 }
 
 /*
@@ -1269,7 +1272,7 @@ static enum object_type packed_to_object_type(struct repository *r,
 		if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) {
 			poi_stack_alloc = alloc_nr(poi_stack_nr);
 			ALLOC_ARRAY(poi_stack, poi_stack_alloc);
-			memcpy(poi_stack, small_poi_stack, sizeof(off_t)*poi_stack_nr);
+			COPY_ARRAY(poi_stack, small_poi_stack, poi_stack_nr);
 		} else {
 			ALLOC_GROW(poi_stack, poi_stack_nr+1, poi_stack_alloc);
 		}
@@ -1679,8 +1682,8 @@ void *unpack_entry(struct repository *r, struct packed_git *p, off_t obj_offset,
 		    && delta_stack == small_delta_stack) {
 			delta_stack_alloc = alloc_nr(delta_stack_nr);
 			ALLOC_ARRAY(delta_stack, delta_stack_alloc);
-			memcpy(delta_stack, small_delta_stack,
-			       sizeof(*delta_stack)*delta_stack_nr);
+			COPY_ARRAY(delta_stack, small_delta_stack,
+				   delta_stack_nr);
 		} else {
 			ALLOC_GROW(delta_stack, delta_stack_nr+1, delta_stack_alloc);
 		}
diff --git a/packfile.h b/packfile.h
index b678d35c0b..81e868d55a 100644
--- a/packfile.h
+++ b/packfile.h
@@ -90,7 +90,7 @@ uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
 unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
 void close_pack_windows(struct packed_git *);
 void close_pack(struct packed_git *);
-void close_all_packs(struct raw_object_store *o);
+void close_object_store(struct raw_object_store *o);
 void unuse_pack(struct pack_window **);
 void clear_delta_base_cache(void);
 struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
diff --git a/pager.c b/pager.c
index 4168460ae9..41446d4f05 100644
--- a/pager.c
+++ b/pager.c
@@ -177,6 +177,26 @@ int term_columns(void)
 	return term_columns_at_startup;
 }
 
+/*
+ * Clear the entire line, leave cursor in first column.
+ */
+void term_clear_line(void)
+{
+	if (is_terminal_dumb())
+		/*
+		 * Fall back to print a terminal width worth of space
+		 * characters (hoping that the terminal is still as wide
+		 * as it was upon the first call to term_columns()).
+		 */
+		fprintf(stderr, "\r%*s\r", term_columns(), "");
+	else
+		/*
+		 * On non-dumb terminals use an escape sequence to clear
+		 * the whole line, no matter how wide the terminal.
+		 */
+		fputs("\r\033[K", stderr);
+}
+
 /*
  * How many columns do we need to show this number in decimal?
  */
diff --git a/parse-options-cb.c b/parse-options-cb.c
index a3de795c58..1240a8514e 100644
--- a/parse-options-cb.c
+++ b/parse-options-cb.c
@@ -159,6 +159,23 @@ int parse_opt_tertiary(const struct option *opt, const char *arg, int unset)
 	return 0;
 }
 
+struct option *parse_options_dup(const struct option *o)
+{
+	struct option *opts;
+	int nr = 0;
+
+	while (o && o->type != OPTION_END) {
+		nr++;
+		o++;
+	}
+
+	ALLOC_ARRAY(opts, nr + 1);
+	memcpy(opts, o - nr, sizeof(*o) * nr);
+	memset(opts + nr, 0, sizeof(*opts));
+	opts[nr].type = OPTION_END;
+	return opts;
+}
+
 struct option *parse_options_concat(struct option *a, struct option *b)
 {
 	struct option *ret;
diff --git a/parse-options.h b/parse-options.h
index ac6ba8abf9..a4bd40bb6a 100644
--- a/parse-options.h
+++ b/parse-options.h
@@ -276,6 +276,7 @@ int parse_options_step(struct parse_opt_ctx_t *ctx,
 
 int parse_options_end(struct parse_opt_ctx_t *ctx);
 
+struct option *parse_options_dup(const struct option *a);
 struct option *parse_options_concat(struct option *a, struct option *b);
 
 /*----- some often used options -----*/
diff --git a/patch-ids.c b/patch-ids.c
index f70d396654..e8c150d0c9 100644
--- a/patch-ids.c
+++ b/patch-ids.c
@@ -83,7 +83,7 @@ static int init_patch_id_entry(struct patch_id *patch,
 	if (commit_patch_id(commit, &ids->diffopts, &header_only_patch_id, 1, 0))
 		return -1;
 
-	hashmap_entry_init(patch, sha1hash(header_only_patch_id.hash));
+	hashmap_entry_init(patch, oidhash(&header_only_patch_id));
 	return 0;
 }
 
diff --git a/pretty.c b/pretty.c
index ced0485257..e4ed14effe 100644
--- a/pretty.c
+++ b/pretty.c
@@ -106,8 +106,8 @@ static void setup_commit_formats(void)
 	commit_formats_len = ARRAY_SIZE(builtin_formats);
 	builtin_formats_len = commit_formats_len;
 	ALLOC_GROW(commit_formats, commit_formats_len, commit_formats_alloc);
-	memcpy(commit_formats, builtin_formats,
-	       sizeof(*builtin_formats)*ARRAY_SIZE(builtin_formats));
+	COPY_ARRAY(commit_formats, builtin_formats,
+		   ARRAY_SIZE(builtin_formats));
 
 	git_config(git_pretty_formats_config, NULL);
 }
diff --git a/progress.c b/progress.c
index a2e8cf64a8..095dcd0ddf 100644
--- a/progress.c
+++ b/progress.c
@@ -88,7 +88,6 @@ static void display(struct progress *progress, uint64_t n, const char *done)
 	const char *tp;
 	struct strbuf *counters_sb = &progress->counters_sb;
 	int show_update = 0;
-	int last_count_len = counters_sb->len;
 
 	if (progress->delay && (!progress_update || --progress->delay))
 		return;
@@ -116,26 +115,21 @@ static void display(struct progress *progress, uint64_t n, const char *done)
 	if (show_update) {
 		if (is_foreground_fd(fileno(stderr)) || done) {
 			const char *eol = done ? done : "\r";
-			size_t clear_len = counters_sb->len < last_count_len ?
-					last_count_len - counters_sb->len + 1 :
-					0;
-			size_t progress_line_len = progress->title_len +
-						counters_sb->len + 2;
-			int cols = term_columns();
 
+			term_clear_line();
 			if (progress->split) {
-				fprintf(stderr, "  %s%*s", counters_sb->buf,
-					(int) clear_len, eol);
-			} else if (!done && cols < progress_line_len) {
-				clear_len = progress->title_len + 1 < cols ?
-					    cols - progress->title_len - 1 : 0;
-				fprintf(stderr, "%s:%*s\n  %s%s",
-					progress->title, (int) clear_len, "",
-					counters_sb->buf, eol);
+				fprintf(stderr, "  %s%s", counters_sb->buf,
+					eol);
+			} else if (!done &&
+				   /* The "+ 2" accounts for the ": ". */
+				   term_columns() < progress->title_len +
+						    counters_sb->len + 2) {
+				fprintf(stderr, "%s:\n  %s%s",
+					progress->title, counters_sb->buf, eol);
 				progress->split = 1;
 			} else {
-				fprintf(stderr, "%s: %s%*s", progress->title,
-					counters_sb->buf, (int) clear_len, eol);
+				fprintf(stderr, "%s: %s%s", progress->title,
+					counters_sb->buf, eol);
 			}
 			fflush(stderr);
 		}
diff --git a/reachable.c b/reachable.c
index 0d00a91de4..8f50235b28 100644
--- a/reachable.c
+++ b/reachable.c
@@ -109,7 +109,7 @@ static int add_recent_loose(const struct object_id *oid,
 			    const char *path, void *data)
 {
 	struct stat st;
-	struct object *obj = lookup_object(the_repository, oid->hash);
+	struct object *obj = lookup_object(the_repository, oid);
 
 	if (obj && obj->flags & SEEN)
 		return 0;
@@ -134,7 +134,7 @@ static int add_recent_packed(const struct object_id *oid,
 			     struct packed_git *p, uint32_t pos,
 			     void *data)
 {
-	struct object *obj = lookup_object(the_repository, oid->hash);
+	struct object *obj = lookup_object(the_repository, oid);
 
 	if (obj && obj->flags & SEEN)
 		return 0;
diff --git a/read-cache.c b/read-cache.c
index 4dd22f4f6e..c701f7f8b8 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -549,7 +549,7 @@ static int index_name_stage_pos(const struct index_state *istate, const char *na
 	first = 0;
 	last = istate->cache_nr;
 	while (last > first) {
-		int next = (last + first) >> 1;
+		int next = first + ((last - first) >> 1);
 		struct cache_entry *ce = istate->cache[next];
 		int cmp = cache_name_stage_compare(name, namelen, stage, ce->name, ce_namelen(ce), ce_stage(ce));
 		if (!cmp)
diff --git a/ref-filter.c b/ref-filter.c
index 8500671bc6..791f0648a6 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -20,6 +20,8 @@
 #include "commit-slab.h"
 #include "commit-graph.h"
 #include "commit-reach.h"
+#include "worktree.h"
+#include "hashmap.h"
 
 static struct ref_msg {
 	const char *gone;
@@ -75,6 +77,27 @@ static struct expand_data {
 	struct object_info info;
 } oi, oi_deref;
 
+struct ref_to_worktree_entry {
+	struct hashmap_entry ent; /* must be the first member! */
+	struct worktree *wt; /* key is wt->head_ref */
+};
+
+static int ref_to_worktree_map_cmpfnc(const void *unused_lookupdata,
+				      const void *existing_hashmap_entry_to_test,
+				      const void *key,
+				      const void *keydata_aka_refname)
+{
+	const struct ref_to_worktree_entry *e = existing_hashmap_entry_to_test;
+	const struct ref_to_worktree_entry *k = key;
+	return strcmp(e->wt->head_ref,
+		keydata_aka_refname ? keydata_aka_refname : k->wt->head_ref);
+}
+
+static struct ref_to_worktree_map {
+	struct hashmap map;
+	struct worktree **worktrees;
+} ref_to_worktree_map;
+
 /*
  * An atom is a valid field atom listed below, possibly prefixed with
  * a "*" to denote deref_tag().
@@ -480,6 +503,7 @@ static struct {
 	{ "flag", SOURCE_NONE },
 	{ "HEAD", SOURCE_NONE, FIELD_STR, head_atom_parser },
 	{ "color", SOURCE_NONE, FIELD_STR, color_atom_parser },
+	{ "worktreepath", SOURCE_NONE },
 	{ "align", SOURCE_NONE, FIELD_STR, align_atom_parser },
 	{ "end", SOURCE_NONE },
 	{ "if", SOURCE_NONE, FIELD_STR, if_atom_parser },
@@ -1447,35 +1471,35 @@ char *get_head_description(void)
 	struct wt_status_state state;
 	memset(&state, 0, sizeof(state));
 	wt_status_get_state(the_repository, &state, 1);
+
+	/*
+	 * The ( character must be hard-coded and not part of a localizable
+	 * string, since the description is used as a sort key and compared
+	 * with ref names.
+	 */
+	strbuf_addch(&desc, '(');
 	if (state.rebase_in_progress ||
 	    state.rebase_interactive_in_progress) {
 		if (state.branch)
-			strbuf_addf(&desc, _("(no branch, rebasing %s)"),
+			strbuf_addf(&desc, _("no branch, rebasing %s"),
 				    state.branch);
 		else
-			strbuf_addf(&desc, _("(no branch, rebasing detached HEAD %s)"),
+			strbuf_addf(&desc, _("no branch, rebasing detached HEAD %s"),
 				    state.detached_from);
 	} else if (state.bisect_in_progress)
-		strbuf_addf(&desc, _("(no branch, bisect started on %s)"),
+		strbuf_addf(&desc, _("no branch, bisect started on %s"),
 			    state.branch);
 	else if (state.detached_from) {
 		if (state.detached_at)
-			/*
-			 * TRANSLATORS: make sure this matches "HEAD
-			 * detached at " in wt-status.c
-			 */
-			strbuf_addf(&desc, _("(HEAD detached at %s)"),
-				state.detached_from);
+			strbuf_addstr(&desc, HEAD_DETACHED_AT);
 		else
-			/*
-			 * TRANSLATORS: make sure this matches "HEAD
-			 * detached from " in wt-status.c
-			 */
-			strbuf_addf(&desc, _("(HEAD detached from %s)"),
-				state.detached_from);
+			strbuf_addstr(&desc, HEAD_DETACHED_FROM);
+		strbuf_addstr(&desc, state.detached_from);
 	}
 	else
-		strbuf_addstr(&desc, _("(no branch)"));
+		strbuf_addstr(&desc, _("no branch"));
+	strbuf_addch(&desc, ')');
+
 	free(state.branch);
 	free(state.onto);
 	free(state.detached_from);
@@ -1531,6 +1555,48 @@ static int get_object(struct ref_array_item *ref, int deref, struct object **obj
 	return 0;
 }
 
+static void populate_worktree_map(struct hashmap *map, struct worktree **worktrees)
+{
+	int i;
+
+	for (i = 0; worktrees[i]; i++) {
+		if (worktrees[i]->head_ref) {
+			struct ref_to_worktree_entry *entry;
+			entry = xmalloc(sizeof(*entry));
+			entry->wt = worktrees[i];
+			hashmap_entry_init(entry, strhash(worktrees[i]->head_ref));
+
+			hashmap_add(map, entry);
+		}
+	}
+}
+
+static void lazy_init_worktree_map(void)
+{
+	if (ref_to_worktree_map.worktrees)
+		return;
+
+	ref_to_worktree_map.worktrees = get_worktrees(0);
+	hashmap_init(&(ref_to_worktree_map.map), ref_to_worktree_map_cmpfnc, NULL, 0);
+	populate_worktree_map(&(ref_to_worktree_map.map), ref_to_worktree_map.worktrees);
+}
+
+static char *get_worktree_path(const struct used_atom *atom, const struct ref_array_item *ref)
+{
+	struct hashmap_entry entry;
+	struct ref_to_worktree_entry *lookup_result;
+
+	lazy_init_worktree_map();
+
+	hashmap_entry_init(&entry, strhash(ref->refname));
+	lookup_result = hashmap_get(&(ref_to_worktree_map.map), &entry, ref->refname);
+
+	if (lookup_result)
+		return xstrdup(lookup_result->wt->path);
+	else
+		return xstrdup("");
+}
+
 /*
  * Parse the object referred by ref, and grab needed value.
  */
@@ -1568,6 +1634,13 @@ static int populate_value(struct ref_array_item *ref, struct strbuf *err)
 
 		if (starts_with(name, "refname"))
 			refname = get_refname(atom, ref);
+		else if (!strcmp(name, "worktreepath")) {
+			if (ref->kind == FILTER_REFS_BRANCHES)
+				v->s = get_worktree_path(atom, ref);
+			else
+				v->s = xstrdup("");
+			continue;
+		}
 		else if (starts_with(name, "symref"))
 			refname = get_symref(atom, ref);
 		else if (starts_with(name, "upstream")) {
@@ -2051,6 +2124,11 @@ void ref_array_clear(struct ref_array *array)
 		free_array_item(array->items[i]);
 	FREE_AND_NULL(array->items);
 	array->nr = array->alloc = 0;
+	if (ref_to_worktree_map.worktrees) {
+		hashmap_free(&(ref_to_worktree_map.map), 1);
+		free_worktrees(ref_to_worktree_map.worktrees);
+		ref_to_worktree_map.worktrees = NULL;
+	}
 }
 
 static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
diff --git a/refs.c b/refs.c
index b8a8430c96..cd297ee4bd 100644
--- a/refs.c
+++ b/refs.c
@@ -379,7 +379,7 @@ static int filter_refs(const char *refname, const struct object_id *oid,
 
 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
 {
-	struct object *o = lookup_unknown_object(name->hash);
+	struct object *o = lookup_unknown_object(name);
 
 	if (o->type == OBJ_NONE) {
 		int type = oid_object_info(the_repository, name, NULL);
diff --git a/sequencer.c b/sequencer.c
index ab74b6baf1..cf262701e8 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -279,7 +279,7 @@ static const char *gpg_sign_opt_quoted(struct replay_opts *opts)
 int sequencer_remove_state(struct replay_opts *opts)
 {
 	struct strbuf buf = STRBUF_INIT;
-	int i;
+	int i, ret = 0;
 
 	if (is_rebase_i(opts) &&
 	    strbuf_read_file(&buf, rebase_path_refs_to_delete(), 0) > 0) {
@@ -288,8 +288,10 @@ int sequencer_remove_state(struct replay_opts *opts)
 			char *eol = strchr(p, '\n');
 			if (eol)
 				*eol = '\0';
-			if (delete_ref("(rebase -i) cleanup", p, NULL, 0) < 0)
+			if (delete_ref("(rebase -i) cleanup", p, NULL, 0) < 0) {
 				warning(_("could not delete '%s'"), p);
+				ret = -1;
+			}
 			if (!eol)
 				break;
 			p = eol + 1;
@@ -305,10 +307,11 @@ int sequencer_remove_state(struct replay_opts *opts)
 
 	strbuf_reset(&buf);
 	strbuf_addstr(&buf, get_dir(opts));
-	remove_dir_recursively(&buf, 0);
+	if (remove_dir_recursively(&buf, 0))
+		ret = error(_("could not remove '%s'"), buf.buf);
 	strbuf_release(&buf);
 
-	return 0;
+	return ret;
 }
 
 static const char *action_name(const struct replay_opts *opts)
@@ -2311,19 +2314,21 @@ static int have_finished_the_last_pick(void)
 	return ret;
 }
 
-void sequencer_post_commit_cleanup(struct repository *r)
+void sequencer_post_commit_cleanup(struct repository *r, int verbose)
 {
 	struct replay_opts opts = REPLAY_OPTS_INIT;
 	int need_cleanup = 0;
 
 	if (file_exists(git_path_cherry_pick_head(r))) {
-		unlink(git_path_cherry_pick_head(r));
+		if (!unlink(git_path_cherry_pick_head(r)) && verbose)
+			warning(_("cancelling a cherry picking in progress"));
 		opts.action = REPLAY_PICK;
 		need_cleanup = 1;
 	}
 
 	if (file_exists(git_path_revert_head(r))) {
-		unlink(git_path_revert_head(r));
+		if (!unlink(git_path_revert_head(r)) && verbose)
+			warning(_("cancelling a revert in progress"));
 		opts.action = REPLAY_REVERT;
 		need_cleanup = 1;
 	}
@@ -3736,8 +3741,11 @@ static int pick_commits(struct repository *r,
 			unlink(git_path_merge_head(the_repository));
 			delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 
-			if (item->command == TODO_BREAK)
+			if (item->command == TODO_BREAK) {
+				if (!opts->verbose)
+					term_clear_line();
 				return stopped_at_head(r);
+			}
 		}
 		if (item->command <= TODO_SQUASH) {
 			if (is_rebase_i(opts))
@@ -3759,11 +3767,14 @@ static int pick_commits(struct repository *r,
 			}
 			if (item->command == TODO_EDIT) {
 				struct commit *commit = item->commit;
-				if (!res)
+				if (!res) {
+					if (!opts->verbose)
+						term_clear_line();
 					fprintf(stderr,
 						_("Stopped at %s...  %.*s\n"),
 						short_commit_name(commit),
 						item->arg_len, arg);
+				}
 				return error_with_patch(r, commit,
 					arg, item->arg_len, opts, res, !res);
 			}
@@ -3801,6 +3812,8 @@ static int pick_commits(struct repository *r,
 			int saved = *end_of_arg;
 			struct stat st;
 
+			if (!opts->verbose)
+				term_clear_line();
 			*end_of_arg = '\0';
 			res = do_exec(r, arg);
 			*end_of_arg = saved;
@@ -3959,10 +3972,13 @@ static int pick_commits(struct repository *r,
 		}
 		apply_autostash(opts);
 
-		if (!opts->quiet)
+		if (!opts->quiet) {
+			if (!opts->verbose)
+				term_clear_line();
 			fprintf(stderr,
 				"Successfully rebased and updated %s.\n",
 				head_ref.buf);
+		}
 
 		strbuf_release(&buf);
 		strbuf_release(&head_ref);
diff --git a/sequencer.h b/sequencer.h
index 0c494b83d4..3d0b68c34c 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -200,6 +200,6 @@ int read_author_script(const char *path, char **name, char **email, char **date,
 void parse_strategy_opts(struct replay_opts *opts, char *raw_opts);
 int write_basic_state(struct replay_opts *opts, const char *head_name,
 		      struct commit *onto, const char *orig_head);
-void sequencer_post_commit_cleanup(struct repository *r);
+void sequencer_post_commit_cleanup(struct repository *r, int verbose);
 int sequencer_get_last_command(struct repository* r,
 			       enum replay_action *action);
diff --git a/sh-i18n--envsubst.c b/sh-i18n--envsubst.c
index cecfdd36c7..e7430b9aa8 100644
--- a/sh-i18n--envsubst.c
+++ b/sh-i18n--envsubst.c
@@ -249,7 +249,7 @@ sorted_string_list_member (const string_list_ty *slp, const char *s)
 	{
 	  /* Here we know that if s is in the list, it is at an index j
 	     with j1 <= j < j2.  */
-	  size_t j = (j1 + j2) >> 1;
+	  size_t j = j1 + ((j2 - j1) >> 1);
 	  int result = strcmp (slp->item[j], s);
 
 	  if (result > 0)
diff --git a/sha1-name.c b/sha1-name.c
index 728e6f1f61..49855ad24f 100644
--- a/sha1-name.c
+++ b/sha1-name.c
@@ -801,7 +801,7 @@ static int get_oid_basic(struct repository *r, const char *str, int len,
 	"because it will be ignored when you just specify 40-hex. These refs\n"
 	"may be created by mistake. For example,\n"
 	"\n"
-	"  git checkout -b $br $(git rev-parse ...)\n"
+	"  git switch -c $br $(git rev-parse ...)\n"
 	"\n"
 	"where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
 	"examine these refs and maybe delete them. Turn this message off by\n"
diff --git a/t/helper/test-example-decorate.c b/t/helper/test-example-decorate.c
index a20a6161e4..c8a1cde7d2 100644
--- a/t/helper/test-example-decorate.c
+++ b/t/helper/test-example-decorate.c
@@ -26,8 +26,8 @@ int cmd__example_decorate(int argc, const char **argv)
 	 * Add 2 objects, one with a non-NULL decoration and one with a NULL
 	 * decoration.
 	 */
-	one = lookup_unknown_object(one_oid.hash);
-	two = lookup_unknown_object(two_oid.hash);
+	one = lookup_unknown_object(&one_oid);
+	two = lookup_unknown_object(&two_oid);
 	ret = add_decoration(&n, one, &decoration_a);
 	if (ret)
 		BUG("when adding a brand-new object, NULL should be returned");
@@ -56,7 +56,7 @@ int cmd__example_decorate(int argc, const char **argv)
 	ret = lookup_decoration(&n, two);
 	if (ret != &decoration_b)
 		BUG("lookup should return added declaration");
-	three = lookup_unknown_object(three_oid.hash);
+	three = lookup_unknown_object(&three_oid);
 	ret = lookup_decoration(&n, three);
 	if (ret)
 		BUG("lookup for unknown object should return NULL");
diff --git a/t/lib-patch-mode.sh b/t/lib-patch-mode.sh
index 06c3c91762..cfd76bf987 100644
--- a/t/lib-patch-mode.sh
+++ b/t/lib-patch-mode.sh
@@ -2,28 +2,40 @@
 
 . ./test-lib.sh
 
+# set_state <path> <worktree-content> <index-content>
+#
+# Prepare the content for path in worktree and the index as specified.
 set_state () {
 	echo "$3" > "$1" &&
 	git add "$1" &&
 	echo "$2" > "$1"
 }
 
+# save_state <path>
+#
+# Save index/worktree content of <path> in the files _worktree_<path>
+# and _index_<path>
 save_state () {
 	noslash="$(echo "$1" | tr / _)" &&
 	cat "$1" > _worktree_"$noslash" &&
 	git show :"$1" > _index_"$noslash"
 }
 
+# set_and_save_state <path> <worktree-content> <index-content>
 set_and_save_state () {
 	set_state "$@" &&
 	save_state "$1"
 }
 
+# verify_state <path> <expected-worktree-content> <expected-index-content>
 verify_state () {
 	test "$(cat "$1")" = "$2" &&
 	test "$(git show :"$1")" = "$3"
 }
 
+# verify_saved_state <path>
+#
+# Call verify_state with expected contents from the last save_state
 verify_saved_state () {
 	noslash="$(echo "$1" | tr / _)" &&
 	verify_state "$1" "$(cat _worktree_"$noslash")" "$(cat _index_"$noslash")"
diff --git a/t/t0001-init.sh b/t/t0001-init.sh
index 0276d14a0b..26f8206326 100755
--- a/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@ -311,8 +311,8 @@ test_expect_success 'init prefers command line to GIT_DIR' '
 test_expect_success 'init with separate gitdir' '
 	rm -rf newdir &&
 	git init --separate-git-dir realgitdir newdir &&
-	echo "gitdir: $(pwd)/realgitdir" >expected &&
-	test_cmp expected newdir/.git &&
+	newdir_git="$(cat newdir/.git)" &&
+	test_cmp_fspath "$(pwd)/realgitdir" "${newdir_git#gitdir: }" &&
 	test_path_is_dir realgitdir/refs
 '
 
@@ -361,12 +361,9 @@ test_expect_success 're-init on .git file' '
 '
 
 test_expect_success 're-init to update git link' '
-	(
-	cd newdir &&
-	git init --separate-git-dir ../surrealgitdir
-	) &&
-	echo "gitdir: $(pwd)/surrealgitdir" >expected &&
-	test_cmp expected newdir/.git &&
+	git -C newdir init --separate-git-dir ../surrealgitdir &&
+	newdir_git="$(cat newdir/.git)" &&
+	test_cmp_fspath "$(pwd)/surrealgitdir" "${newdir_git#gitdir: }" &&
 	test_path_is_dir surrealgitdir/refs &&
 	test_path_is_missing realgitdir/refs
 '
@@ -374,12 +371,9 @@ test_expect_success 're-init to update git link' '
 test_expect_success 're-init to move gitdir' '
 	rm -rf newdir realgitdir surrealgitdir &&
 	git init newdir &&
-	(
-	cd newdir &&
-	git init --separate-git-dir ../realgitdir
-	) &&
-	echo "gitdir: $(pwd)/realgitdir" >expected &&
-	test_cmp expected newdir/.git &&
+	git -C newdir init --separate-git-dir ../realgitdir &&
+	newdir_git="$(cat newdir/.git)" &&
+	test_cmp_fspath "$(pwd)/realgitdir" "${newdir_git#gitdir: }" &&
 	test_path_is_dir realgitdir/refs
 '
 
@@ -473,8 +467,8 @@ test_expect_success MINGW 'redirect std handles' '
 		GIT_REDIRECT_STDOUT=output.txt \
 		GIT_REDIRECT_STDERR="2>&1" \
 		git rev-parse --git-dir --verify refs/invalid &&
-	printf ".git\nfatal: Needed a single revision\n" >expect &&
-	test_cmp expect output.txt
+	grep "^\\.git\$" output.txt &&
+	grep "Needed a single revision" output.txt
 '
 
 test_done
diff --git a/t/t0007-git-var.sh b/t/t0007-git-var.sh
index 5868a87352..1f600e2cae 100755
--- a/t/t0007-git-var.sh
+++ b/t/t0007-git-var.sh
@@ -17,7 +17,7 @@ test_expect_success 'get GIT_COMMITTER_IDENT' '
 	test_cmp expect actual
 '
 
-test_expect_success !AUTOIDENT 'requested identites are strict' '
+test_expect_success !FAIL_PREREQS,!AUTOIDENT 'requested identites are strict' '
 	(
 		sane_unset GIT_COMMITTER_NAME &&
 		sane_unset GIT_COMMITTER_EMAIL &&
diff --git a/t/t1090-sparse-checkout-scope.sh b/t/t1090-sparse-checkout-scope.sh
index 090b7fc3d3..40cc004326 100755
--- a/t/t1090-sparse-checkout-scope.sh
+++ b/t/t1090-sparse-checkout-scope.sh
@@ -31,20 +31,6 @@ test_expect_success 'perform sparse checkout of master' '
 	test_path_is_file c
 '
 
-test_expect_success 'checkout -b checkout.optimizeNewBranch interaction' '
-	cp .git/info/sparse-checkout .git/info/sparse-checkout.bak &&
-	test_when_finished "
-		mv -f .git/info/sparse-checkout.bak .git/info/sparse-checkout
-		git checkout master
-	" &&
-	echo "/b" >>.git/info/sparse-checkout &&
-	test "$(git ls-files -t b)" = "S b" &&
-	git -c checkout.optimizeNewBranch=true checkout -b fast &&
-	test "$(git ls-files -t b)" = "S b" &&
-	git checkout -b slow &&
-	test "$(git ls-files -t b)" = "H b"
-'
-
 test_expect_success 'merge feature branch into sparse checkout of master' '
 	git merge feature &&
 	test_path_is_file a &&
diff --git a/t/t1305-config-include.sh b/t/t1305-config-include.sh
index 579a86b7f8..9571e366f8 100755
--- a/t/t1305-config-include.sh
+++ b/t/t1305-config-include.sh
@@ -309,6 +309,45 @@ test_expect_success SYMLINKS 'conditional include, gitdir matching symlink, icas
 	)
 '
 
+test_expect_success 'conditional include, onbranch' '
+	echo "[includeIf \"onbranch:foo-branch\"]path=bar9" >>.git/config &&
+	echo "[test]nine=9" >.git/bar9 &&
+	git checkout -b master &&
+	test_must_fail git config test.nine &&
+	git checkout -b foo-branch &&
+	echo 9 >expect &&
+	git config test.nine >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'conditional include, onbranch, wildcard' '
+	echo "[includeIf \"onbranch:?oo-*/**\"]path=bar10" >>.git/config &&
+	echo "[test]ten=10" >.git/bar10 &&
+	git checkout -b not-foo-branch/a &&
+	test_must_fail git config test.ten &&
+
+	echo 10 >expect &&
+	git checkout -b foo-branch/a/b/c &&
+	git config test.ten >actual &&
+	test_cmp expect actual &&
+
+	git checkout -b moo-bar/a &&
+	git config test.ten >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'conditional include, onbranch, implicit /** for /' '
+	echo "[includeIf \"onbranch:foo-dir/\"]path=bar11" >>.git/config &&
+	echo "[test]eleven=11" >.git/bar11 &&
+	git checkout -b not-foo-dir/a &&
+	test_must_fail git config test.eleven &&
+
+	echo 11 >expect &&
+	git checkout -b foo-dir/a/b/c &&
+	git config test.eleven >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'include cycles are detected' '
 	cat >.gitconfig <<-\EOF &&
 	[test]value = gitconfig
diff --git a/t/t2014-checkout-switch.sh b/t/t2014-checkout-switch.sh
new file mode 100755
index 0000000000..ccfb147113
--- /dev/null
+++ b/t/t2014-checkout-switch.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+
+test_description='Peter MacMillan'
+. ./test-lib.sh
+
+test_expect_success setup '
+	echo Hello >file &&
+	git add file &&
+	test_tick &&
+	git commit -m V1 &&
+	echo Hello world >file &&
+	git add file &&
+	git checkout -b other
+'
+
+test_expect_success 'check all changes are staged' '
+	git diff --exit-code
+'
+
+test_expect_success 'second commit' '
+	git commit -m V2
+'
+
+test_expect_success 'check' '
+	git diff --cached --exit-code
+'
+
+test_done
diff --git a/t/t2014-switch.sh b/t/t2014-switch.sh
deleted file mode 100755
index ccfb147113..0000000000
--- a/t/t2014-switch.sh
+++ /dev/null
@@ -1,28 +0,0 @@
-#!/bin/sh
-
-test_description='Peter MacMillan'
-. ./test-lib.sh
-
-test_expect_success setup '
-	echo Hello >file &&
-	git add file &&
-	test_tick &&
-	git commit -m V1 &&
-	echo Hello world >file &&
-	git add file &&
-	git checkout -b other
-'
-
-test_expect_success 'check all changes are staged' '
-	git diff --exit-code
-'
-
-test_expect_success 'second commit' '
-	git commit -m V2
-'
-
-test_expect_success 'check' '
-	git diff --cached --exit-code
-'
-
-test_done
diff --git a/t/t2020-checkout-detach.sh b/t/t2020-checkout-detach.sh
index 1fa670625c..b748db9946 100755
--- a/t/t2020-checkout-detach.sh
+++ b/t/t2020-checkout-detach.sh
@@ -195,16 +195,22 @@ test_expect_success 'describe_detached_head prints no SHA-1 ellipsis when not as
 
 	# The first detach operation is more chatty than the following ones.
 	cat >1st_detach <<-EOF &&
-	Note: checking out 'HEAD^'.
+	Note: switching to 'HEAD^'.
 
 	You are in 'detached HEAD' state. You can look around, make experimental
 	changes and commit them, and you can discard any commits you make in this
-	state without impacting any branches by performing another checkout.
+	state without impacting any branches by switching back to a branch.
 
 	If you want to create a new branch to retain commits you create, you may
-	do so (now or later) by using -b with the checkout command again. Example:
+	do so (now or later) by using -c with the switch command. Example:
 
-	  git checkout -b <new-branch-name>
+	  git switch -c <new-branch-name>
+
+	Or undo this operation with:
+
+	  git switch -
+
+	Turn off this advice by setting config variable advice.detachedHead to false
 
 	HEAD is now at \$commit three
 	EOF
@@ -271,16 +277,22 @@ test_expect_success 'describe_detached_head does print SHA-1 ellipsis when asked
 
 	# The first detach operation is more chatty than the following ones.
 	cat >1st_detach <<-EOF &&
-	Note: checking out 'HEAD^'.
+	Note: switching to 'HEAD^'.
 
 	You are in 'detached HEAD' state. You can look around, make experimental
 	changes and commit them, and you can discard any commits you make in this
-	state without impacting any branches by performing another checkout.
+	state without impacting any branches by switching back to a branch.
 
 	If you want to create a new branch to retain commits you create, you may
-	do so (now or later) by using -b with the checkout command again. Example:
+	do so (now or later) by using -c with the switch command. Example:
+
+	  git switch -c <new-branch-name>
+
+	Or undo this operation with:
+
+	  git switch -
 
-	  git checkout -b <new-branch-name>
+	Turn off this advice by setting config variable advice.detachedHead to false
 
 	HEAD is now at \$commit... three
 	EOF
diff --git a/t/t2060-switch.sh b/t/t2060-switch.sh
new file mode 100755
index 0000000000..f9efa29dfb
--- /dev/null
+++ b/t/t2060-switch.sh
@@ -0,0 +1,96 @@
+#!/bin/sh
+
+test_description='switch basic functionality'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit first &&
+	git branch first-branch &&
+	test_commit second &&
+	test_commit third &&
+	git remote add origin nohost:/nopath &&
+	git update-ref refs/remotes/origin/foo first-branch
+'
+
+test_expect_success 'switch branch no arguments' '
+	test_must_fail git switch
+'
+
+test_expect_success 'switch branch' '
+	git switch first-branch &&
+	test_path_is_missing second.t
+'
+
+test_expect_success 'switch and detach' '
+	test_when_finished git switch master &&
+	test_must_fail git switch master^{commit} &&
+	git switch --detach master^{commit} &&
+	test_must_fail git symbolic-ref HEAD
+'
+
+test_expect_success 'switch and detach current branch' '
+	test_when_finished git switch master &&
+	git switch master &&
+	git switch --detach &&
+	test_must_fail git symbolic-ref HEAD
+'
+
+test_expect_success 'switch and create branch' '
+	test_when_finished git switch master &&
+	git switch -c temp master^ &&
+	test_cmp_rev master^ refs/heads/temp &&
+	echo refs/heads/temp >expected-branch &&
+	git symbolic-ref HEAD >actual-branch &&
+	test_cmp expected-branch actual-branch
+'
+
+test_expect_success 'force create branch from HEAD' '
+	test_when_finished git switch master &&
+	git switch --detach master &&
+	test_must_fail git switch -c temp &&
+	git switch -C temp &&
+	test_cmp_rev master refs/heads/temp &&
+	echo refs/heads/temp >expected-branch &&
+	git symbolic-ref HEAD >actual-branch &&
+	test_cmp expected-branch actual-branch
+'
+
+test_expect_success 'new orphan branch from empty' '
+	test_when_finished git switch master &&
+	test_must_fail git switch --orphan new-orphan HEAD &&
+	git switch --orphan new-orphan &&
+	test_commit orphan &&
+	git cat-file commit refs/heads/new-orphan >commit &&
+	! grep ^parent commit &&
+	git ls-files >tracked-files &&
+	echo orphan.t >expected &&
+	test_cmp expected tracked-files
+'
+
+test_expect_success 'switching ignores file of same branch name' '
+	test_when_finished git switch master &&
+	: >first-branch &&
+	git switch first-branch &&
+	echo refs/heads/first-branch >expected &&
+	git symbolic-ref HEAD >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'guess and create branch ' '
+	test_when_finished git switch master &&
+	test_must_fail git switch --no-guess foo &&
+	git switch foo &&
+	echo refs/heads/foo >expected &&
+	git symbolic-ref HEAD >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'not switching when something is in progress' '
+	test_when_finished rm -f .git/MERGE_HEAD &&
+	# fake a merge-in-progress
+	cp .git/HEAD .git/MERGE_HEAD &&
+	test_must_fail git switch -d @^
+'
+
+test_done
diff --git a/t/t2070-restore.sh b/t/t2070-restore.sh
new file mode 100755
index 0000000000..2650df1966
--- /dev/null
+++ b/t/t2070-restore.sh
@@ -0,0 +1,98 @@
+#!/bin/sh
+
+test_description='restore basic functionality'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit first &&
+	echo first-and-a-half >>first.t &&
+	git add first.t &&
+	test_commit second &&
+	echo one >one &&
+	echo two >two &&
+	echo untracked >untracked &&
+	echo ignored >ignored &&
+	echo /ignored >.gitignore &&
+	git add one two .gitignore &&
+	git update-ref refs/heads/one master
+'
+
+test_expect_success 'restore without pathspec is not ok' '
+	test_must_fail git restore &&
+	test_must_fail git restore --source=first
+'
+
+test_expect_success 'restore a file, ignoring branch of same name' '
+	cat one >expected &&
+	echo dirty >>one &&
+	git restore one &&
+	test_cmp expected one
+'
+
+test_expect_success 'restore a file on worktree from another ref' '
+	test_when_finished git reset --hard &&
+	git cat-file blob first:./first.t >expected &&
+	git restore --source=first first.t &&
+	test_cmp expected first.t &&
+	git cat-file blob HEAD:./first.t >expected &&
+	git show :first.t >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'restore a file in the index from another ref' '
+	test_when_finished git reset --hard &&
+	git cat-file blob first:./first.t >expected &&
+	git restore --source=first --staged first.t &&
+	git show :first.t >actual &&
+	test_cmp expected actual &&
+	git cat-file blob HEAD:./first.t >expected &&
+	test_cmp expected first.t
+'
+
+test_expect_success 'restore a file in both the index and worktree from another ref' '
+	test_when_finished git reset --hard &&
+	git cat-file blob first:./first.t >expected &&
+	git restore --source=first --staged --worktree first.t &&
+	git show :first.t >actual &&
+	test_cmp expected actual &&
+	test_cmp expected first.t
+'
+
+test_expect_success 'restore --staged uses HEAD as source' '
+	test_when_finished git reset --hard &&
+	git cat-file blob :./first.t >expected &&
+	echo index-dirty >>first.t &&
+	git add first.t &&
+	git restore --staged first.t &&
+	git cat-file blob :./first.t >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'restore --ignore-unmerged ignores unmerged entries' '
+	git init unmerged &&
+	(
+		cd unmerged &&
+		echo one >unmerged &&
+		echo one >common &&
+		git add unmerged common &&
+		git commit -m common &&
+		git switch -c first &&
+		echo first >unmerged &&
+		git commit -am first &&
+		git switch -c second master &&
+		echo second >unmerged &&
+		git commit -am second &&
+		test_must_fail git merge first &&
+
+		echo dirty >>common &&
+		test_must_fail git restore . &&
+
+		git restore --ignore-unmerged --quiet . >output 2>&1 &&
+		git diff common >diff-output &&
+		test_must_be_empty output &&
+		test_must_be_empty diff-output
+	)
+'
+
+test_done
diff --git a/t/t2071-restore-patch.sh b/t/t2071-restore-patch.sh
new file mode 100755
index 0000000000..98b2476e7c
--- /dev/null
+++ b/t/t2071-restore-patch.sh
@@ -0,0 +1,110 @@
+#!/bin/sh
+
+test_description='git restore --patch'
+
+. ./lib-patch-mode.sh
+
+test_expect_success PERL 'setup' '
+	mkdir dir &&
+	echo parent >dir/foo &&
+	echo dummy >bar &&
+	git add bar dir/foo &&
+	git commit -m initial &&
+	test_tick &&
+	test_commit second dir/foo head &&
+	set_and_save_state bar bar_work bar_index &&
+	save_head
+'
+
+test_expect_success PERL 'restore -p without pathspec is fine' '
+	echo q >cmd &&
+	git restore -p <cmd
+'
+
+# note: bar sorts before dir/foo, so the first 'n' is always to skip 'bar'
+
+test_expect_success PERL 'saying "n" does nothing' '
+	set_and_save_state dir/foo work head &&
+	test_write_lines n n | git restore -p &&
+	verify_saved_state bar &&
+	verify_saved_state dir/foo
+'
+
+test_expect_success PERL 'git restore -p' '
+	set_and_save_state dir/foo work head &&
+	test_write_lines n y | git restore -p &&
+	verify_saved_state bar &&
+	verify_state dir/foo head head
+'
+
+test_expect_success PERL 'git restore -p with staged changes' '
+	set_state dir/foo work index &&
+	test_write_lines n y | git restore -p &&
+	verify_saved_state bar &&
+	verify_state dir/foo index index
+'
+
+test_expect_success PERL 'git restore -p --source=HEAD' '
+	set_state dir/foo work index &&
+	# the third n is to get out in case it mistakenly does not apply
+	test_write_lines n y n | git restore -p --source=HEAD &&
+	verify_saved_state bar &&
+	verify_state dir/foo head index
+'
+
+test_expect_success PERL 'git restore -p --source=HEAD^' '
+	set_state dir/foo work index &&
+	# the third n is to get out in case it mistakenly does not apply
+	test_write_lines n y n | git restore -p --source=HEAD^ &&
+	verify_saved_state bar &&
+	verify_state dir/foo parent index
+'
+
+test_expect_success PERL 'git restore -p handles deletion' '
+	set_state dir/foo work index &&
+	rm dir/foo &&
+	test_write_lines n y | git restore -p &&
+	verify_saved_state bar &&
+	verify_state dir/foo index index
+'
+
+# The idea in the rest is that bar sorts first, so we always say 'y'
+# first and if the path limiter fails it'll apply to bar instead of
+# dir/foo.  There's always an extra 'n' to reject edits to dir/foo in
+# the failure case (and thus get out of the loop).
+
+test_expect_success PERL 'path limiting works: dir' '
+	set_state dir/foo work head &&
+	test_write_lines y n | git restore -p dir &&
+	verify_saved_state bar &&
+	verify_state dir/foo head head
+'
+
+test_expect_success PERL 'path limiting works: -- dir' '
+	set_state dir/foo work head &&
+	test_write_lines y n | git restore -p -- dir &&
+	verify_saved_state bar &&
+	verify_state dir/foo head head
+'
+
+test_expect_success PERL 'path limiting works: HEAD^ -- dir' '
+	set_state dir/foo work head &&
+	# the third n is to get out in case it mistakenly does not apply
+	test_write_lines y n n | git restore -p --source=HEAD^ -- dir &&
+	verify_saved_state bar &&
+	verify_state dir/foo parent head
+'
+
+test_expect_success PERL 'path limiting works: foo inside dir' '
+	set_state dir/foo work head &&
+	# the third n is to get out in case it mistakenly does not apply
+	test_write_lines y n n | (cd dir && git restore -p foo) &&
+	verify_saved_state bar &&
+	verify_state dir/foo head head
+'
+
+test_expect_success PERL 'none of this moved HEAD' '
+	verify_saved_head
+'
+
+test_done
diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index e9d7084d19..411a70b0ce 100755
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -206,18 +206,22 @@ test_expect_success 'git branch -M baz bam should succeed when baz is checked ou
 	git worktree add -f bazdir2 baz &&
 	git branch -M baz bam &&
 	test $(git -C bazdir rev-parse --abbrev-ref HEAD) = bam &&
-	test $(git -C bazdir2 rev-parse --abbrev-ref HEAD) = bam
+	test $(git -C bazdir2 rev-parse --abbrev-ref HEAD) = bam &&
+	rm -r bazdir bazdir2 &&
+	git worktree prune
 '
 
 test_expect_success 'git branch -M baz bam should succeed within a worktree in which baz is checked out' '
 	git checkout -b baz &&
-	git worktree add -f bazdir3 baz &&
+	git worktree add -f bazdir baz &&
 	(
-		cd bazdir3 &&
+		cd bazdir &&
 		git branch -M baz bam &&
 		test $(git rev-parse --abbrev-ref HEAD) = bam
 	) &&
-	test $(git rev-parse --abbrev-ref HEAD) = bam
+	test $(git rev-parse --abbrev-ref HEAD) = bam &&
+	rm -r bazdir &&
+	git worktree prune
 '
 
 test_expect_success 'git branch -M master should work when master is checked out' '
@@ -804,7 +808,9 @@ test_expect_success 'test deleting branch without config' '
 test_expect_success 'deleting currently checked out branch fails' '
 	git worktree add -b my7 my7 &&
 	test_must_fail git -C my7 branch -d my7 &&
-	test_must_fail git branch -d my7
+	test_must_fail git branch -d my7 &&
+	rm -r my7 &&
+	git worktree prune
 '
 
 test_expect_success 'test --track without .fetch entries' '
diff --git a/t/t3203-branch-output.sh b/t/t3203-branch-output.sh
index be55148930..71818b90f0 100755
--- a/t/t3203-branch-output.sh
+++ b/t/t3203-branch-output.sh
@@ -136,10 +136,13 @@ test_expect_success 'git branch `--show-current` works properly with worktrees'
 	branch-two
 	EOF
 	git checkout branch-one &&
-	git worktree add worktree branch-two &&
+	test_when_finished "
+		git worktree remove worktree_dir
+	" &&
+	git worktree add worktree_dir branch-two &&
 	{
 		git branch --show-current &&
-		git -C worktree branch --show-current
+		git -C worktree_dir branch --show-current
 	} >actual &&
 	test_cmp expect actual
 '
@@ -284,6 +287,24 @@ test_expect_success 'git branch --format option' '
 	test_i18ncmp expect actual
 '
 
+test_expect_success 'worktree colors correct' '
+	cat >expect <<-EOF &&
+	* <GREEN>(HEAD detached from fromtag)<RESET>
+	  ambiguous<RESET>
+	  branch-one<RESET>
+	+ <CYAN>branch-two<RESET>
+	  master<RESET>
+	  ref-to-branch<RESET> -> branch-one
+	  ref-to-remote<RESET> -> origin/branch-one
+	EOF
+	git worktree add worktree_dir branch-two &&
+	git branch --color >actual.raw &&
+	rm -r worktree_dir &&
+	git worktree prune &&
+	test_decode_color <actual.raw >actual &&
+	test_i18ncmp expect actual
+'
+
 test_expect_success "set up color tests" '
 	echo "<RED>master<RESET>" >expect.color &&
 	echo "master" >expect.bare &&
@@ -308,4 +329,23 @@ test_expect_success '--color overrides auto-color' '
 	test_cmp expect.color actual
 '
 
+test_expect_success 'verbose output lists worktree path' '
+	one=$(git rev-parse --short HEAD) &&
+	two=$(git rev-parse --short master) &&
+	cat >expect <<-EOF &&
+	* (HEAD detached from fromtag) $one one
+	  ambiguous                    $one one
+	  branch-one                   $two two
+	+ branch-two                   $one ($(pwd)/worktree_dir) one
+	  master                       $two two
+	  ref-to-branch                $two two
+	  ref-to-remote                $two two
+	EOF
+	git worktree add worktree_dir branch-two &&
+	git branch -vv >actual &&
+	rm -r worktree_dir &&
+	git worktree prune &&
+	test_i18ncmp expect actual
+'
+
 test_done
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 1723e1a858..461dd539ff 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -75,11 +75,10 @@ test_expect_success 'rebase --keep-empty' '
 	test_line_count = 6 actual
 '
 
-cat > expect <<EOF
-error: nothing to do
-EOF
-
 test_expect_success 'rebase -i with empty HEAD' '
+	cat >expect <<-\EOF &&
+	error: nothing to do
+	EOF
 	set_fake_editor &&
 	test_must_fail env FAKE_LINES="1 exec_true" git rebase -i HEAD^ >actual 2>&1 &&
 	test_i18ncmp expect actual
@@ -237,25 +236,23 @@ test_expect_success 'exchange two commits' '
 	test G = $(git cat-file commit HEAD | sed -ne \$p)
 '
 
-cat > expect << EOF
-diff --git a/file1 b/file1
-index f70f10e..fd79235 100644
---- a/file1
-+++ b/file1
-@@ -1 +1 @@
--A
-+G
-EOF
-
-cat > expect2 << EOF
-<<<<<<< HEAD
-D
-=======
-G
->>>>>>> 5d18e54... G
-EOF
-
 test_expect_success 'stop on conflicting pick' '
+	cat >expect <<-\EOF &&
+	diff --git a/file1 b/file1
+	index f70f10e..fd79235 100644
+	--- a/file1
+	+++ b/file1
+	@@ -1 +1 @@
+	-A
+	+G
+	EOF
+	cat >expect2 <<-\EOF &&
+	<<<<<<< HEAD
+	D
+	=======
+	G
+	>>>>>>> 5d18e54... G
+	EOF
 	git tag new-branch1 &&
 	set_fake_editor &&
 	test_must_fail git rebase -i master &&
@@ -495,15 +492,14 @@ test_expect_success 'commit message retained after conflict' '
 	git branch -D conflict-squash
 '
 
-cat > expect-squash-fixup << EOF
-B
-
-D
+test_expect_success C_LOCALE_OUTPUT 'squash and fixup generate correct log messages' '
+	cat >expect-squash-fixup <<-\EOF &&
+	B
 
-ONCE
-EOF
+	D
 
-test_expect_success C_LOCALE_OUTPUT 'squash and fixup generate correct log messages' '
+	ONCE
+	EOF
 	git checkout -b squash-fixup E &&
 	base=$(git rev-parse HEAD~4) &&
 	set_fake_editor &&
@@ -799,13 +795,12 @@ test_expect_success 'rebase -i can copy notes' '
 	test "a note" = "$(git notes show HEAD)"
 '
 
-cat >expect <<EOF
-an earlier note
-
-a note
-EOF
-
 test_expect_success 'rebase -i can copy notes over a fixup' '
+	cat >expect <<-\EOF &&
+	an earlier note
+
+	a note
+	EOF
 	git reset --hard n3 &&
 	git notes add -m"an earlier note" n2 &&
 	set_fake_editor &&
@@ -1031,7 +1026,7 @@ test_expect_success 'rebase -i --root reword root commit' '
 	test -z "$(git show -s --format=%p HEAD^)"
 '
 
-test_expect_success 'rebase -i --root when root has untracked file confilct' '
+test_expect_success 'rebase -i --root when root has untracked file conflict' '
 	test_when_finished "reset_rebase" &&
 	git checkout -b failing-root-pick A &&
 	echo x >file2 &&
@@ -1304,52 +1299,37 @@ test_expect_success 'rebase -i respects rebase.missingCommitsCheck = ignore' '
 		actual
 '
 
-cat >expect <<EOF
-Warning: some commits may have been dropped accidentally.
-Dropped commits (newer to older):
- - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
-To avoid this message, use "drop" to explicitly remove a commit.
-
-Use 'git config rebase.missingCommitsCheck' to change the level of warnings.
-The possible behaviours are: ignore, warn, error.
-
-Rebasing (1/4)
-Rebasing (2/4)
-Rebasing (3/4)
-Rebasing (4/4)
-Successfully rebased and updated refs/heads/missing-commit.
-EOF
-
-cr_to_nl () {
-	tr '\015' '\012'
-}
-
 test_expect_success 'rebase -i respects rebase.missingCommitsCheck = warn' '
+	cat >expect <<-EOF &&
+	Warning: some commits may have been dropped accidentally.
+	Dropped commits (newer to older):
+	 - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
+	To avoid this message, use "drop" to explicitly remove a commit.
+	EOF
 	test_config rebase.missingCommitsCheck warn &&
 	rebase_setup_and_clean missing-commit &&
 	set_fake_editor &&
 	FAKE_LINES="1 2 3 4" \
 		git rebase -i --root 2>actual.2 &&
-	cr_to_nl <actual.2 >actual &&
+	head -n4 actual.2 >actual &&
 	test_i18ncmp expect actual &&
 	test D = $(git cat-file commit HEAD | sed -ne \$p)
 '
 
-cat >expect <<EOF
-Warning: some commits may have been dropped accidentally.
-Dropped commits (newer to older):
- - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
- - $(git rev-list --pretty=oneline --abbrev-commit -1 master~2)
-To avoid this message, use "drop" to explicitly remove a commit.
-
-Use 'git config rebase.missingCommitsCheck' to change the level of warnings.
-The possible behaviours are: ignore, warn, error.
-
-You can fix this with 'git rebase --edit-todo' and then run 'git rebase --continue'.
-Or you can abort the rebase with 'git rebase --abort'.
-EOF
-
 test_expect_success 'rebase -i respects rebase.missingCommitsCheck = error' '
+	cat >expect <<-EOF &&
+	Warning: some commits may have been dropped accidentally.
+	Dropped commits (newer to older):
+	 - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
+	 - $(git rev-list --pretty=oneline --abbrev-commit -1 master~2)
+	To avoid this message, use "drop" to explicitly remove a commit.
+
+	Use '\''git config rebase.missingCommitsCheck'\'' to change the level of warnings.
+	The possible behaviours are: ignore, warn, error.
+
+	You can fix this with '\''git rebase --edit-todo'\'' and then run '\''git rebase --continue'\''.
+	Or you can abort the rebase with '\''git rebase --abort'\''.
+	EOF
 	test_config rebase.missingCommitsCheck error &&
 	rebase_setup_and_clean missing-commit &&
 	set_fake_editor &&
diff --git a/t/t3420-rebase-autostash.sh b/t/t3420-rebase-autostash.sh
index 2d1094e483..9186e90127 100755
--- a/t/t3420-rebase-autostash.sh
+++ b/t/t3420-rebase-autostash.sh
@@ -49,7 +49,7 @@ create_expected_success_interactive () {
 	$(grep "^Created autostash: [0-9a-f][0-9a-f]*\$" actual)
 	HEAD is now at $(git rev-parse --short feature-branch) third commit
 	Rebasing (1/2)QRebasing (2/2)QApplied autostash.
-	Successfully rebased and updated refs/heads/rebased-feature-branch.
+	Q                                                                                QSuccessfully rebased and updated refs/heads/rebased-feature-branch.
 	EOF
 }
 
@@ -73,7 +73,7 @@ create_expected_failure_interactive () {
 	Rebasing (1/2)QRebasing (2/2)QApplying autostash resulted in conflicts.
 	Your changes are safe in the stash.
 	You can run "git stash pop" or "git stash drop" at any time.
-	Successfully rebased and updated refs/heads/rebased-feature-branch.
+	Q                                                                                QSuccessfully rebased and updated refs/heads/rebased-feature-branch.
 	EOF
 }
 
diff --git a/t/t3430-rebase-merges.sh b/t/t3430-rebase-merges.sh
index 2315649f43..7b6c4847ad 100755
--- a/t/t3430-rebase-merges.sh
+++ b/t/t3430-rebase-merges.sh
@@ -237,8 +237,24 @@ test_expect_success 'refs/rewritten/* is worktree-local' '
 	test_cmp_rev HEAD "$(cat wt/b)"
 '
 
+test_expect_success '--abort cleans up refs/rewritten' '
+	git checkout -b abort-cleans-refs-rewritten H &&
+	GIT_SEQUENCE_EDITOR="echo break >>" git rebase -ir @^ &&
+	git rev-parse --verify refs/rewritten/onto &&
+	git rebase --abort &&
+	test_must_fail git rev-parse --verify refs/rewritten/onto
+'
+
+test_expect_success '--quit cleans up refs/rewritten' '
+	git checkout -b quit-cleans-refs-rewritten H &&
+	GIT_SEQUENCE_EDITOR="echo break >>" git rebase -ir @^ &&
+	git rev-parse --verify refs/rewritten/onto &&
+	git rebase --quit &&
+	test_must_fail git rev-parse --verify refs/rewritten/onto
+'
+
 test_expect_success 'post-rewrite hook and fixups work for merges' '
-	git checkout -b post-rewrite &&
+	git checkout -b post-rewrite H &&
 	test_commit same1 &&
 	git reset --hard HEAD^ &&
 	test_commit same2 &&
diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh
index 65dfbc033a..69991a3168 100755
--- a/t/t3701-add-interactive.sh
+++ b/t/t3701-add-interactive.sh
@@ -639,4 +639,12 @@ test_expect_success 'add -p patch editing works with pathological context lines'
 	test_cmp expected-2 actual
 '
 
+test_expect_success 'checkout -p works with pathological context lines' '
+	test_write_lines a a a a a a >a &&
+	git add a &&
+	test_write_lines a b a b a b a b a b a > a&&
+	test_write_lines s n n y q | git checkout -p &&
+	test_write_lines a b a b a a b a b a >expect &&
+	test_cmp expect a
+'
 test_done
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index ea30d5f6a0..b22e671608 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -708,6 +708,24 @@ test_expect_success 'invalid ref of the form "n", n >= N' '
 	git stash drop
 '
 
+test_expect_success 'valid ref of the form "n", n < N' '
+	git stash clear &&
+	echo bar5 >file &&
+	echo bar6 >file2 &&
+	git add file2 &&
+	git stash &&
+	git stash show 0 &&
+	git stash branch tmp 0 &&
+	git checkout master &&
+	git stash &&
+	git stash apply 0 &&
+	git reset --hard &&
+	git stash pop 0 &&
+	git stash &&
+	git stash drop 0 &&
+	test_must_fail git stash drop
+'
+
 test_expect_success 'branch: do not drop the stash if the branch exists' '
 	git stash clear &&
 	echo foo >file &&
diff --git a/t/t4018-diff-funcname.sh b/t/t4018-diff-funcname.sh
index 22f9f88f0a..9261d6d3a0 100755
--- a/t/t4018-diff-funcname.sh
+++ b/t/t4018-diff-funcname.sh
@@ -43,6 +43,7 @@ diffpatterns="
 	php
 	python
 	ruby
+	rust
 	tex
 	custom1
 	custom2
diff --git a/t/t4018/rust-fn b/t/t4018/rust-fn
new file mode 100644
index 0000000000..cbe02155f1
--- /dev/null
+++ b/t/t4018/rust-fn
@@ -0,0 +1,5 @@
+pub(self) fn RIGHT<T>(x: &[T]) where T: Debug {
+    let _ = x;
+    // a comment
+    let a = ChangeMe;
+}
diff --git a/t/t4018/rust-impl b/t/t4018/rust-impl
new file mode 100644
index 0000000000..09df3cd93b
--- /dev/null
+++ b/t/t4018/rust-impl
@@ -0,0 +1,5 @@
+impl<'a, T: AsRef<[u8]>>  std::RIGHT for Git<'a> {
+
+    pub fn ChangeMe(&self) -> () {
+    }
+}
diff --git a/t/t4018/rust-struct b/t/t4018/rust-struct
new file mode 100644
index 0000000000..76aff1c0d8
--- /dev/null
+++ b/t/t4018/rust-struct
@@ -0,0 +1,5 @@
+#[derive(Debug)]
+pub(super) struct RIGHT<'a> {
+    name: &'a str,
+    age: ChangeMe,
+}
diff --git a/t/t4018/rust-trait b/t/t4018/rust-trait
new file mode 100644
index 0000000000..ea397f09ed
--- /dev/null
+++ b/t/t4018/rust-trait
@@ -0,0 +1,5 @@
+unsafe trait RIGHT<T> {
+    fn len(&self) -> u32;
+    fn ChangeMe(&self, n: u32) -> T;
+    fn iter<F>(&self, f: F) where F: Fn(T);
+}
diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index 840ad4d8ac..5267c4be20 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -23,6 +23,14 @@ test_expect_success 'write graph with no packs' '
 	test_path_is_file info/commit-graph
 '
 
+test_expect_success 'close with correct error on bad input' '
+	cd "$TRASH_DIRECTORY/full" &&
+	echo doesnotexist >in &&
+	{ git commit-graph write --stdin-packs <in 2>stderr; ret=$?; } &&
+	test "$ret" = 1 &&
+	test_i18ngrep "error adding pack" stderr
+'
+
 test_expect_success 'create commits and repack' '
 	cd "$TRASH_DIRECTORY/full" &&
 	for i in $(test_seq 3)
diff --git a/t/t5514-fetch-multiple.sh b/t/t5514-fetch-multiple.sh
index 0030c92e1a..5426d4b5ab 100755
--- a/t/t5514-fetch-multiple.sh
+++ b/t/t5514-fetch-multiple.sh
@@ -105,9 +105,12 @@ test_expect_success 'git fetch --multiple (two remotes)' '
 	 git remote rm origin &&
 	 git remote add one ../one &&
 	 git remote add two ../two &&
-	 git fetch --multiple one two &&
+	 GIT_TRACE=1 git fetch --multiple one two 2>trace &&
 	 git branch -r > output &&
-	 test_cmp ../expect output)
+	 test_cmp ../expect output &&
+	 grep "built-in: git gc" trace >gc &&
+	 test_line_count = 1 gc
+	)
 '
 
 test_expect_success 'git fetch --multiple (bad remote names)' '
diff --git a/t/t5541-http-push-smart.sh b/t/t5541-http-push-smart.sh
index 8ef8763e06..2e4802e206 100755
--- a/t/t5541-http-push-smart.sh
+++ b/t/t5541-http-push-smart.sh
@@ -213,7 +213,7 @@ test_expect_success TTY 'push shows progress when stderr is a tty' '
 	cd "$ROOT_PATH"/test_repo_clone &&
 	test_commit noisy &&
 	test_terminal git push >output 2>&1 &&
-	test_i18ngrep "^Writing objects" output
+	test_i18ngrep "Writing objects" output
 '
 
 test_expect_success TTY 'push --quiet silences status and progress' '
@@ -228,7 +228,7 @@ test_expect_success TTY 'push --no-progress silences progress but not status' '
 	test_commit no-progress &&
 	test_terminal git push --no-progress >output 2>&1 &&
 	test_i18ngrep "^To http" output &&
-	test_i18ngrep ! "^Writing objects" output
+	test_i18ngrep ! "Writing objects" output
 '
 
 test_expect_success 'push --progress shows progress to non-tty' '
@@ -236,7 +236,7 @@ test_expect_success 'push --progress shows progress to non-tty' '
 	test_commit progress &&
 	git push --progress >output 2>&1 &&
 	test_i18ngrep "^To http" output &&
-	test_i18ngrep "^Writing objects" output
+	test_i18ngrep "Writing objects" output
 '
 
 test_expect_success 'http push gives sane defaults to reflog' '
diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index ac74626a7b..cb11f13d6d 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -199,7 +199,7 @@ test_expect_success 'GIT_SMART_HTTP can disable smart http' '
 
 test_expect_success 'invalid Content-Type rejected' '
 	test_must_fail git clone $HTTPD_URL/broken_smart/repo.git 2>actual &&
-	grep "not valid:" actual
+	test_i18ngrep "not valid:" actual
 '
 
 test_expect_success 'create namespaced refs' '
@@ -466,7 +466,7 @@ test_expect_success 'GIT_TRACE_CURL_NO_DATA prevents data from being traced' '
 
 test_expect_success 'server-side error detected' '
 	test_must_fail git clone $HTTPD_URL/error_smart/repo.git 2>actual &&
-	grep "server-side error" actual
+	test_i18ngrep "server-side error" actual
 '
 
 test_done
diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh
index 9a8f9886b3..b91ef548f8 100755
--- a/t/t5616-partial-clone.sh
+++ b/t/t5616-partial-clone.sh
@@ -244,11 +244,25 @@ test_expect_success 'fetch what is specified on CLI even if already promised' '
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd
 
-# Converts bytes into a form suitable for inclusion in a sed command. For
-# example, "printf 'ab\r\n' | hex_unpack" results in '\x61\x62\x0d\x0a'.
-sed_escape () {
-	perl -e '$/ = undef; $input = <>; print unpack("H2" x length($input), $input)' |
-		sed 's/\(..\)/\\x\1/g'
+# Converts bytes into their hexadecimal representation. For example,
+# "printf 'ab\r\n' | hex_unpack" results in '61620d0a'.
+hex_unpack () {
+	perl -e '$/ = undef; $input = <>; print unpack("H2" x length($input), $input)'
+}
+
+# Inserts $1 at the start of the string and every 2 characters thereafter.
+intersperse () {
+	sed 's/\(..\)/'$1'\1/g'
+}
+
+# Create a one-time-sed command to replace the existing packfile with $1.
+replace_packfile () {
+	# The protocol requires that the packfile be sent in sideband 1, hence
+	# the extra \x01 byte at the beginning.
+	printf "1,/packfile/!c %04x\\\\x01%s0000" \
+		"$(($(wc -c <$1) + 5))" \
+		"$(hex_unpack <$1 | intersperse '\\x')" \
+		>"$HTTPD_ROOT_PATH/one-time-sed"
 }
 
 test_expect_success 'upon cloning, check that all refs point to objects' '
@@ -270,10 +284,7 @@ test_expect_success 'upon cloning, check that all refs point to objects' '
 	# Replace the existing packfile with the crafted one. The protocol
 	# requires that the packfile be sent in sideband 1, hence the extra
 	# \x01 byte at the beginning.
-	printf "1,/packfile/!c %04x\\\\x01%s0000" \
-		"$(($(wc -c <incomplete.pack) + 5))" \
-		"$(sed_escape <incomplete.pack)" \
-		>"$HTTPD_ROOT_PATH/one-time-sed" &&
+	replace_packfile incomplete.pack &&
 
 	# Use protocol v2 because the sed command looks for the "packfile"
 	# section header.
@@ -313,10 +324,7 @@ test_expect_success 'when partial cloning, tolerate server not sending target of
 	# Replace the existing packfile with the crafted one. The protocol
 	# requires that the packfile be sent in sideband 1, hence the extra
 	# \x01 byte at the beginning.
-	printf "1,/packfile/!c %04x\\\\x01%s0000" \
-		"$(($(wc -c <incomplete.pack) + 5))" \
-		"$(sed_escape <incomplete.pack)" \
-		>"$HTTPD_ROOT_PATH/one-time-sed" &&
+	replace_packfile incomplete.pack &&
 
 	# Use protocol v2 because the sed command looks for the "packfile"
 	# section header.
@@ -331,4 +339,82 @@ test_expect_success 'when partial cloning, tolerate server not sending target of
 	! test -e "$HTTPD_ROOT_PATH/one-time-sed"
 '
 
+test_expect_success 'tolerate server sending REF_DELTA against missing promisor objects' '
+	SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
+	rm -rf "$SERVER" repo &&
+	test_create_repo "$SERVER" &&
+	test_config -C "$SERVER" uploadpack.allowfilter 1 &&
+	test_config -C "$SERVER" uploadpack.allowanysha1inwant 1 &&
+
+	# Create a commit with 2 blobs to be used as delta bases.
+	for i in $(test_seq 10)
+	do
+		echo "this is a line" >>"$SERVER/foo.txt" &&
+		echo "this is another line" >>"$SERVER/have.txt"
+	done &&
+	git -C "$SERVER" add foo.txt have.txt &&
+	git -C "$SERVER" commit -m bar &&
+	git -C "$SERVER" rev-parse HEAD:foo.txt >deltabase_missing &&
+	git -C "$SERVER" rev-parse HEAD:have.txt >deltabase_have &&
+
+	# Clone. The client has deltabase_have but not deltabase_missing.
+	git -c protocol.version=2 clone --no-checkout \
+		--filter=blob:none $HTTPD_URL/one_time_sed/server repo &&
+	git -C repo hash-object -w -- "$SERVER/have.txt" &&
+
+	# Sanity check to ensure that the client does not have
+	# deltabase_missing.
+	git -C repo rev-list --objects --ignore-missing \
+		-- $(cat deltabase_missing) >objlist &&
+	test_line_count = 0 objlist &&
+
+	# Another commit. This commit will be fetched by the client.
+	echo "abcdefghijklmnopqrstuvwxyz" >>"$SERVER/foo.txt" &&
+	echo "abcdefghijklmnopqrstuvwxyz" >>"$SERVER/have.txt" &&
+	git -C "$SERVER" add foo.txt have.txt &&
+	git -C "$SERVER" commit -m baz &&
+
+	# Pack a thin pack containing, among other things, HEAD:foo.txt
+	# delta-ed against HEAD^:foo.txt and HEAD:have.txt delta-ed against
+	# HEAD^:have.txt.
+	printf "%s\n--not\n%s\n" \
+		$(git -C "$SERVER" rev-parse HEAD) \
+		$(git -C "$SERVER" rev-parse HEAD^) |
+		git -C "$SERVER" pack-objects --thin --stdout >thin.pack &&
+
+	# Ensure that the pack contains one delta against HEAD^:foo.txt. Since
+	# the delta contains at least 26 novel characters, the size cannot be
+	# contained in 4 bits, so the object header will take up 2 bytes. The
+	# most significant nybble of the first byte is 0b1111 (0b1 to indicate
+	# that the header continues, and 0b111 to indicate REF_DELTA), followed
+	# by any 3 nybbles, then the OID of the delta base.
+	printf "f.,..%s" $(intersperse "," <deltabase_missing) >want &&
+	hex_unpack <thin.pack | intersperse "," >have &&
+	grep $(cat want) have &&
+
+	# Ensure that the pack contains one delta against HEAD^:have.txt,
+	# similar to the above.
+	printf "f.,..%s" $(intersperse "," <deltabase_have) >want &&
+	hex_unpack <thin.pack | intersperse "," >have &&
+	grep $(cat want) have &&
+
+	replace_packfile thin.pack &&
+
+	# Use protocol v2 because the sed command looks for the "packfile"
+	# section header.
+	test_config -C "$SERVER" protocol.version 2 &&
+
+	# Fetch the thin pack and ensure that index-pack is able to handle the
+	# REF_DELTA object with a missing promisor delta base.
+	GIT_TRACE_PACKET="$(pwd)/trace" git -C repo -c protocol.version=2 fetch &&
+
+	# Ensure that the missing delta base was directly fetched, but not the
+	# one that the client has.
+	grep "want $(cat deltabase_missing)" trace &&
+	! grep "want $(cat deltabase_have)" trace &&
+
+	# Ensure that the one-time-sed script was used.
+	! test -e "$HTTPD_ROOT_PATH/one-time-sed"
+'
+
 test_done
diff --git a/t/t5801-remote-helpers.sh b/t/t5801-remote-helpers.sh
index d04f8007e0..2d6c4a281e 100755
--- a/t/t5801-remote-helpers.sh
+++ b/t/t5801-remote-helpers.sh
@@ -126,7 +126,7 @@ test_expect_success 'forced push' '
 '
 
 test_expect_success 'cloning without refspec' '
-	GIT_REMOTE_TESTGIT_REFSPEC="" \
+	GIT_REMOTE_TESTGIT_NOREFSPEC=1 \
 	git clone "testgit::${PWD}/server" local2 2>error &&
 	test_i18ngrep "this remote helper should implement refspec capability" error &&
 	compare_refs local2 HEAD server HEAD
@@ -135,7 +135,7 @@ test_expect_success 'cloning without refspec' '
 test_expect_success 'pulling without refspecs' '
 	(cd local2 &&
 	git reset --hard &&
-	GIT_REMOTE_TESTGIT_REFSPEC="" git pull 2>../error) &&
+	GIT_REMOTE_TESTGIT_NOREFSPEC=1 git pull 2>../error) &&
 	test_i18ngrep "this remote helper should implement refspec capability" error &&
 	compare_refs local2 HEAD server HEAD
 '
@@ -145,8 +145,8 @@ test_expect_success 'pushing without refspecs' '
 	(cd local2 &&
 	echo content >>file &&
 	git commit -a -m ten &&
-	GIT_REMOTE_TESTGIT_REFSPEC="" &&
-	export GIT_REMOTE_TESTGIT_REFSPEC &&
+	GIT_REMOTE_TESTGIT_NOREFSPEC=1 &&
+	export GIT_REMOTE_TESTGIT_NOREFSPEC &&
 	test_must_fail git push 2>../error) &&
 	test_i18ngrep "remote-helper doesn.t support push; refspec needed" error
 '
@@ -303,4 +303,14 @@ test_expect_success 'fetch url' '
 	compare_refs server HEAD local FETCH_HEAD
 '
 
+test_expect_success 'fetch tag' '
+	(cd server &&
+	 git tag v1.0
+	) &&
+	(cd local &&
+	 git fetch
+	) &&
+	compare_refs local v1.0 server v1.0
+'
+
 test_done
diff --git a/t/t5801/git-remote-testgit b/t/t5801/git-remote-testgit
index 752c763eb6..6b9f0b5dc7 100755
--- a/t/t5801/git-remote-testgit
+++ b/t/t5801/git-remote-testgit
@@ -11,13 +11,15 @@ fi
 url=$2
 
 dir="$GIT_DIR/testgit/$alias"
-prefix="refs/testgit/$alias"
 
-default_refspec="refs/heads/*:${prefix}/heads/*"
+h_refspec="refs/heads/*:refs/testgit/$alias/heads/*"
+t_refspec="refs/tags/*:refs/testgit/$alias/tags/*"
 
-refspec="${GIT_REMOTE_TESTGIT_REFSPEC-$default_refspec}"
-
-test -z "$refspec" && prefix="refs"
+if test -n "$GIT_REMOTE_TESTGIT_NOREFSPEC"
+then
+	h_refspec=""
+	t_refspec=""
+fi
 
 GIT_DIR="$url/.git"
 export GIT_DIR
@@ -40,7 +42,8 @@ do
 	capabilities)
 		echo 'import'
 		echo 'export'
-		test -n "$refspec" && echo "refspec $refspec"
+		test -n "$h_refspec" && echo "refspec $h_refspec"
+		test -n "$t_refspec" && echo "refspec $t_refspec"
 		if test -n "$gitmarks"
 		then
 			echo "*import-marks $gitmarks"
@@ -52,7 +55,7 @@ do
 		echo
 		;;
 	list)
-		git for-each-ref --format='? %(refname)' 'refs/heads/'
+		git for-each-ref --format='? %(refname)' 'refs/heads/' 'refs/tags/'
 		head=$(git symbolic-ref HEAD)
 		echo "@$head HEAD"
 		echo
@@ -81,10 +84,11 @@ do
 
 		echo "feature done"
 		git fast-export \
+			${h_refspec:+"--refspec=$h_refspec"} \
+			${t_refspec:+"--refspec=$t_refspec"} \
 			${testgitmarks:+"--import-marks=$testgitmarks"} \
 			${testgitmarks:+"--export-marks=$testgitmarks"} \
-			$refs |
-		sed -e "s#refs/heads/#${prefix}/heads/#g"
+			$refs
 		echo "done"
 		;;
 	export)
diff --git a/t/t6000-rev-list-misc.sh b/t/t6000-rev-list-misc.sh
index 0507999729..52a9e38d66 100755
--- a/t/t6000-rev-list-misc.sh
+++ b/t/t6000-rev-list-misc.sh
@@ -48,6 +48,26 @@ test_expect_success 'rev-list --objects with pathspecs and copied files' '
 	! grep one output
 '
 
+test_expect_success 'rev-list --objects --no-object-names has no space/names' '
+	git rev-list --objects --no-object-names HEAD >output &&
+	! grep wanted_file output &&
+	! grep unwanted_file output &&
+	! grep " " output
+'
+
+test_expect_success 'rev-list --objects --no-object-names works with cat-file' '
+	git rev-list --objects --no-object-names --all >list-output &&
+	git cat-file --batch-check <list-output >cat-output &&
+	! grep missing cat-output
+'
+
+test_expect_success '--no-object-names and --object-names are last-one-wins' '
+	git rev-list --objects --no-object-names --object-names --all >output &&
+	grep wanted_file output &&
+	git rev-list --objects --object-names --no-object-names --all >output &&
+	! grep wanted_file output
+'
+
 test_expect_success 'rev-list A..B and rev-list ^A B are the same' '
 	git commit --allow-empty -m another &&
 	git tag -a -m "annotated" v1.0 &&
diff --git a/t/t6040-tracking-info.sh b/t/t6040-tracking-info.sh
index 716283b274..febf63f28a 100755
--- a/t/t6040-tracking-info.sh
+++ b/t/t6040-tracking-info.sh
@@ -159,6 +159,19 @@ test_expect_success 'status -s -b --no-ahead-behind (diverged from upstream)' '
 	test_i18ncmp expect actual
 '
 
+cat >expect <<\EOF
+## b1...origin/master [different]
+EOF
+
+test_expect_success 'status.aheadbehind=false status -s -b (diverged from upstream)' '
+	(
+		cd test &&
+		git checkout b1 >/dev/null &&
+		git -c status.aheadbehind=false status -s -b | head -1
+	) >actual &&
+	test_i18ncmp expect actual
+'
+
 cat >expect <<\EOF
 On branch b1
 Your branch and 'origin/master' have diverged,
@@ -174,6 +187,15 @@ test_expect_success 'status --long --branch' '
 	test_i18ncmp expect actual
 '
 
+test_expect_success 'status --long --branch' '
+	(
+		cd test &&
+		git checkout b1 >/dev/null &&
+		git -c status.aheadbehind=true status --long -b | head -3
+	) >actual &&
+	test_i18ncmp expect actual
+'
+
 cat >expect <<\EOF
 On branch b1
 Your branch and 'origin/master' refer to different commits.
@@ -188,6 +210,15 @@ test_expect_success 'status --long --branch --no-ahead-behind' '
 	test_i18ncmp expect actual
 '
 
+test_expect_success 'status.aheadbehind=false status --long --branch' '
+	(
+		cd test &&
+		git checkout b1 >/dev/null &&
+		git -c status.aheadbehind=false status --long -b | head -2
+	) >actual &&
+	test_i18ncmp expect actual
+'
+
 cat >expect <<\EOF
 ## b5...brokenbase [gone]
 EOF
diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh
index fc067ed672..35408d53fd 100755
--- a/t/t6302-for-each-ref-filter.sh
+++ b/t/t6302-for-each-ref-filter.sh
@@ -441,4 +441,17 @@ test_expect_success '--merged is incompatible with --no-merged' '
 	test_must_fail git for-each-ref --merged HEAD --no-merged HEAD
 '
 
+test_expect_success 'validate worktree atom' '
+	cat >expect <<-EOF &&
+	master: $(pwd)
+	master_worktree: $(pwd)/worktree_dir
+	side: not checked out
+	EOF
+	git worktree add -b master_worktree worktree_dir master &&
+	git for-each-ref --format="%(refname:short): %(if)%(worktreepath)%(then)%(worktreepath)%(else)not checked out%(end)" refs/heads/ >actual &&
+	rm -r worktree_dir &&
+	git worktree prune &&
+	test_cmp expect actual
+'
+
 test_done
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index 6aeeb279a0..80eb13d94e 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -932,6 +932,27 @@ test_expect_success GPG \
 	test_cmp expect actual
 '
 
+get_tag_header gpgsign-enabled $commit commit $time >expect
+echo "A message" >>expect
+echo '-----BEGIN PGP SIGNATURE-----' >>expect
+test_expect_success GPG \
+	'git tag configured tag.gpgsign enables GPG sign' \
+	'test_config tag.gpgsign true &&
+	git tag -m "A message" gpgsign-enabled &&
+	get_tag_msg gpgsign-enabled>actual &&
+	test_cmp expect actual
+'
+
+get_tag_header no-sign $commit commit $time >expect
+echo "A message" >>expect
+test_expect_success GPG \
+	'git tag --no-sign configured tag.gpgsign skip GPG sign' \
+	'test_config tag.gpgsign true &&
+	git tag -a --no-sign -m "A message" no-sign &&
+	get_tag_msg no-sign>actual &&
+	test_cmp expect actual
+'
+
 test_expect_success GPG \
 	'trying to create a signed tag with non-existing -F file should fail' '
 	! test -f nonexistingfile &&
diff --git a/t/t7064-wtstatus-pv2.sh b/t/t7064-wtstatus-pv2.sh
index 11eccc231a..537787e598 100755
--- a/t/t7064-wtstatus-pv2.sh
+++ b/t/t7064-wtstatus-pv2.sh
@@ -445,6 +445,14 @@ test_expect_success 'verify --[no-]ahead-behind with V2 format' '
 		EOF
 
 		git status --ahead-behind --porcelain=v2 --branch --untracked-files=all >actual &&
+		test_cmp expect actual &&
+
+		# Confirm that "status.aheadbehind" DOES NOT work on V2 format.
+		git -c status.aheadbehind=false status --porcelain=v2 --branch --untracked-files=all >actual &&
+		test_cmp expect actual &&
+
+		# Confirm that "status.aheadbehind" DOES NOT work on V2 format.
+		git -c status.aheadbehind=true status --porcelain=v2 --branch --untracked-files=all >actual &&
 		test_cmp expect actual
 	)
 '
diff --git a/t/t7407-submodule-foreach.sh b/t/t7407-submodule-foreach.sh
index 706ae762e0..6b2aa917e1 100755
--- a/t/t7407-submodule-foreach.sh
+++ b/t/t7407-submodule-foreach.sh
@@ -421,4 +421,11 @@ test_expect_success 'option-like arguments passed to foreach commands are not lo
 	test_cmp expected actual
 '
 
+test_expect_success 'option-like arguments passed to foreach recurse correctly' '
+	git -C clone2 submodule foreach --recursive "echo be --an-option" >expect &&
+	git -C clone2 submodule foreach --recursive echo be --an-option >actual &&
+	grep -e "--an-option" expect &&
+	test_cmp expect actual
+'
+
 test_done
diff --git a/t/t7502-commit-porcelain.sh b/t/t7502-commit-porcelain.sh
index 5733d9cd34..14c92e4c25 100755
--- a/t/t7502-commit-porcelain.sh
+++ b/t/t7502-commit-porcelain.sh
@@ -402,7 +402,7 @@ echo editor started >"$(pwd)/.git/result"
 exit 0
 EOF
 
-test_expect_success !AUTOIDENT 'do not fire editor when committer is bogus' '
+test_expect_success !FAIL_PREREQS,!AUTOIDENT 'do not fire editor when committer is bogus' '
 	>.git/result &&
 
 	echo >>negative &&
diff --git a/t/t7508-status.sh b/t/t7508-status.sh
index e1f11293e2..681bc314b4 100755
--- a/t/t7508-status.sh
+++ b/t/t7508-status.sh
@@ -94,13 +94,13 @@ test_expect_success 'status --column' '
 #   (use "git pull" to merge the remote branch into yours)
 #
 # Changes to be committed:
-#   (use "git reset HEAD <file>..." to unstage)
+#   (use "git restore --staged <file>..." to unstage)
 #
 #	new file:   dir2/added
 #
 # Changes not staged for commit:
 #   (use "git add <file>..." to update what will be committed)
-#   (use "git checkout -- <file>..." to discard changes in working directory)
+#   (use "git restore <file>..." to discard changes in working directory)
 #
 #	modified:   dir1/modified
 #
@@ -128,13 +128,13 @@ cat >expect <<\EOF
 #   (use "git pull" to merge the remote branch into yours)
 #
 # Changes to be committed:
-#   (use "git reset HEAD <file>..." to unstage)
+#   (use "git restore --staged <file>..." to unstage)
 #
 #	new file:   dir2/added
 #
 # Changes not staged for commit:
 #   (use "git add <file>..." to update what will be committed)
-#   (use "git checkout -- <file>..." to discard changes in working directory)
+#   (use "git restore <file>..." to discard changes in working directory)
 #
 #	modified:   dir1/modified
 #
@@ -278,13 +278,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -347,13 +347,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -420,13 +420,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -484,13 +484,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -542,13 +542,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -605,13 +605,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   ../dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   modified
 
@@ -676,13 +676,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	<GREEN>new file:   dir2/added<RESET>
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	<RED>modified:   dir1/modified<RESET>
 
@@ -802,13 +802,13 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -852,7 +852,7 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   dir1/modified
 
@@ -896,14 +896,14 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 	new file:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -956,14 +956,14 @@ and have 1 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	new file:   dir2/added
 	new file:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1019,7 +1019,7 @@ and have 2 and 2 different commits each, respectively.
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1068,14 +1068,14 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD^1 <file>..." to unstage)
+  (use "git restore --source=HEAD^1 --staged <file>..." to unstage)
 
 	new file:   dir2/added
 	new file:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1123,13 +1123,13 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1235,13 +1235,13 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
   (commit or discard the untracked or modified content in submodules)
 
 	modified:   dir1/modified
@@ -1295,13 +1295,13 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 	modified:   sm (new commits)
@@ -1379,13 +1379,13 @@ cat > expect << EOF
 ;   (use "git pull" to merge the remote branch into yours)
 ;
 ; Changes to be committed:
-;   (use "git reset HEAD <file>..." to unstage)
+;   (use "git restore --staged <file>..." to unstage)
 ;
 ;	modified:   sm
 ;
 ; Changes not staged for commit:
 ;   (use "git add <file>..." to update what will be committed)
-;   (use "git checkout -- <file>..." to discard changes in working directory)
+;   (use "git restore <file>..." to discard changes in working directory)
 ;
 ;	modified:   dir1/modified
 ;	modified:   sm (new commits)
@@ -1431,7 +1431,7 @@ and have 2 and 2 different commits each, respectively.
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1458,13 +1458,13 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
@@ -1581,13 +1581,13 @@ and have 2 and 2 different commits each, respectively.
   (use "git pull" to merge the remote branch into yours)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   sm
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   dir1/modified
 
diff --git a/t/t7512-status-help.sh b/t/t7512-status-help.sh
index c1eb72555d..b9f5d73423 100755
--- a/t/t7512-status-help.sh
+++ b/t/t7512-status-help.sh
@@ -85,7 +85,7 @@ You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
   (use "git rebase --abort" to check out the original branch)
 
 Unmerged paths:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
 	both modified:   main.txt
@@ -110,7 +110,7 @@ You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
   (all conflicts fixed: run "git rebase --continue")
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   main.txt
 
@@ -148,7 +148,7 @@ You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO
   (use "git rebase --abort" to check out the original branch)
 
 Unmerged paths:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
 	both modified:   main.txt
@@ -176,7 +176,7 @@ You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO
   (all conflicts fixed: run "git rebase --continue")
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   main.txt
 
@@ -246,7 +246,7 @@ You are currently splitting a commit while rebasing branch '\''split_commit'\''
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   main.txt
 
@@ -354,7 +354,7 @@ You are currently splitting a commit while rebasing branch '\''several_edits'\''
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   main.txt
 
@@ -453,7 +453,7 @@ You are currently splitting a commit while rebasing branch '\''several_edits'\''
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   main.txt
 
@@ -557,7 +557,7 @@ You are currently splitting a commit while rebasing branch '\''several_edits'\''
 
 Changes not staged for commit:
   (use "git add <file>..." to update what will be committed)
-  (use "git checkout -- <file>..." to discard changes in working directory)
+  (use "git restore <file>..." to discard changes in working directory)
 
 	modified:   main.txt
 
@@ -834,7 +834,7 @@ You are currently reverting commit $TO_REVERT.
   (use "git revert --abort" to cancel the revert operation)
 
 Unmerged paths:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
 	both modified:   to-revert.txt
@@ -855,7 +855,7 @@ You are currently reverting commit $TO_REVERT.
   (use "git revert --abort" to cancel the revert operation)
 
 Changes to be committed:
-  (use "git reset HEAD <file>..." to unstage)
+  (use "git restore --staged <file>..." to unstage)
 
 	modified:   to-revert.txt
 
diff --git a/t/t7513-interpret-trailers.sh b/t/t7513-interpret-trailers.sh
index c441861331..f19202b509 100755
--- a/t/t7513-interpret-trailers.sh
+++ b/t/t7513-interpret-trailers.sh
@@ -538,33 +538,50 @@ test_expect_success 'with 2 files arguments' '
 	test_cmp expected actual
 '
 
-test_expect_success 'with message that has comments' '
-	cat basic_message >message_with_comments &&
-	sed -e "s/ Z\$/ /" >>message_with_comments <<-\EOF &&
-		# comment
-
-		# other comment
-		Cc: Z
-		# yet another comment
-		Reviewed-by: Johan
-		Reviewed-by: Z
-		# last comment
-
-	EOF
-	cat basic_patch >>message_with_comments &&
-	cat basic_message >expected &&
-	cat >>expected <<-\EOF &&
-		# comment
-
-		Reviewed-by: Johan
-		Cc: Peff
-		# last comment
-
-	EOF
-	cat basic_patch >>expected &&
-	git interpret-trailers --trim-empty --trailer "Cc: Peff" message_with_comments >actual &&
-	test_cmp expected actual
-'
+# Cover multiple comment characters with the same test input.
+for char in "#" ";"
+do
+	case "$char" in
+	"#")
+		# This is the default, so let's explicitly _not_
+		# set any config to make sure it behaves as we expect.
+		;;
+	*)
+		config="-c core.commentChar=$char"
+		;;
+	esac
+
+	test_expect_success "with message that has comments ($char)" '
+		cat basic_message >message_with_comments &&
+		sed -e "s/ Z\$/ /" \
+		    -e "s/#/$char/g" >>message_with_comments <<-EOF &&
+			# comment
+
+			# other comment
+			Cc: Z
+			# yet another comment
+			Reviewed-by: Johan
+			Reviewed-by: Z
+			# last comment
+
+		EOF
+		cat basic_patch >>message_with_comments &&
+		cat basic_message >expected &&
+		sed -e "s/#/$char/g" >>expected <<-\EOF &&
+			# comment
+
+			Reviewed-by: Johan
+			Cc: Peff
+			# last comment
+
+		EOF
+		cat basic_patch >>expected &&
+		git $config interpret-trailers \
+			--trim-empty --trailer "Cc: Peff" \
+			message_with_comments >actual &&
+		test_cmp expected actual
+	'
+done
 
 test_expect_success 'with message that has an old style conflict block' '
 	cat basic_message >message_with_comments &&
diff --git a/t/t7610-mergetool.sh b/t/t7610-mergetool.sh
index 5b61c10a9c..ad288ddc69 100755
--- a/t/t7610-mergetool.sh
+++ b/t/t7610-mergetool.sh
@@ -131,17 +131,21 @@ test_expect_success 'custom mergetool' '
 	git checkout -b test$test_count branch1 &&
 	git submodule update -N &&
 	test_must_fail git merge master &&
-	( yes "" | git mergetool both ) &&
-	( yes "" | git mergetool file1 file1 ) &&
-	( yes "" | git mergetool file2 "spaced name" ) &&
-	( yes "" | git mergetool subdir/file3 ) &&
-	( yes "d" | git mergetool file11 ) &&
-	( yes "d" | git mergetool file12 ) &&
-	( yes "l" | git mergetool submod ) &&
-	test "$(cat file1)" = "master updated" &&
-	test "$(cat file2)" = "master new" &&
-	test "$(cat subdir/file3)" = "master new sub" &&
-	test "$(cat submod/bar)" = "branch1 submodule" &&
+	yes "" | git mergetool both &&
+	yes "" | git mergetool file1 file1 &&
+	yes "" | git mergetool file2 "spaced name" &&
+	yes "" | git mergetool subdir/file3 &&
+	yes "d" | git mergetool file11 &&
+	yes "d" | git mergetool file12 &&
+	yes "l" | git mergetool submod &&
+	echo "master updated" >expect &&
+	test_cmp expect file1 &&
+	echo "master new" >expect &&
+	test_cmp expect file2 &&
+	echo "master new sub" >expect &&
+	test_cmp expect subdir/file3 &&
+	echo "branch1 submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git commit -m "branch1 resolved with mergetool"
 '
 
@@ -153,17 +157,21 @@ test_expect_success 'gui mergetool' '
 	git checkout -b test$test_count branch1 &&
 	git submodule update -N &&
 	test_must_fail git merge master &&
-	( yes "" | git mergetool --gui both ) &&
-	( yes "" | git mergetool -g file1 file1 ) &&
-	( yes "" | git mergetool --gui file2 "spaced name" ) &&
-	( yes "" | git mergetool --gui subdir/file3 ) &&
-	( yes "d" | git mergetool --gui file11 ) &&
-	( yes "d" | git mergetool --gui file12 ) &&
-	( yes "l" | git mergetool --gui submod ) &&
-	test "$(cat file1)" = "gui master updated" &&
-	test "$(cat file2)" = "gui master new" &&
-	test "$(cat subdir/file3)" = "gui master new sub" &&
-	test "$(cat submod/bar)" = "branch1 submodule" &&
+	yes "" | git mergetool --gui both &&
+	yes "" | git mergetool -g file1 file1 &&
+	yes "" | git mergetool --gui file2 "spaced name" &&
+	yes "" | git mergetool --gui subdir/file3 &&
+	yes "d" | git mergetool --gui file11 &&
+	yes "d" | git mergetool --gui file12 &&
+	yes "l" | git mergetool --gui submod &&
+	echo "gui master updated" >expect &&
+	test_cmp expect file1 &&
+	echo "gui master new" >expect &&
+	test_cmp expect file2 &&
+	echo "gui master new sub" >expect &&
+	test_cmp expect subdir/file3 &&
+	echo "branch1 submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git commit -m "branch1 resolved with mergetool"
 '
 
@@ -172,17 +180,21 @@ test_expect_success 'gui mergetool without merge.guitool set falls back to merge
 	git checkout -b test$test_count branch1 &&
 	git submodule update -N &&
 	test_must_fail git merge master &&
-	( yes "" | git mergetool --gui both ) &&
-	( yes "" | git mergetool -g file1 file1 ) &&
-	( yes "" | git mergetool --gui file2 "spaced name" ) &&
-	( yes "" | git mergetool --gui subdir/file3 ) &&
-	( yes "d" | git mergetool --gui file11 ) &&
-	( yes "d" | git mergetool --gui file12 ) &&
-	( yes "l" | git mergetool --gui submod ) &&
-	test "$(cat file1)" = "master updated" &&
-	test "$(cat file2)" = "master new" &&
-	test "$(cat subdir/file3)" = "master new sub" &&
-	test "$(cat submod/bar)" = "branch1 submodule" &&
+	yes "" | git mergetool --gui both &&
+	yes "" | git mergetool -g file1 file1 &&
+	yes "" | git mergetool --gui file2 "spaced name" &&
+	yes "" | git mergetool --gui subdir/file3 &&
+	yes "d" | git mergetool --gui file11 &&
+	yes "d" | git mergetool --gui file12 &&
+	yes "l" | git mergetool --gui submod &&
+	echo "master updated" >expect &&
+	test_cmp expect file1 &&
+	echo "master new" >expect &&
+	test_cmp expect file2 &&
+	echo "master new sub" >expect &&
+	test_cmp expect subdir/file3 &&
+	echo "branch1 submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git commit -m "branch1 resolved with mergetool"
 '
 
@@ -195,19 +207,20 @@ test_expect_success 'mergetool crlf' '
 	test_config core.autocrlf true &&
 	git checkout -b test$test_count branch1 &&
 	test_must_fail git merge master &&
-	( yes "" | git mergetool file1 ) &&
-	( yes "" | git mergetool file2 ) &&
-	( yes "" | git mergetool "spaced name" ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "" | git mergetool subdir/file3 ) &&
-	( yes "d" | git mergetool file11 ) &&
-	( yes "d" | git mergetool file12 ) &&
-	( yes "r" | git mergetool submod ) &&
+	yes "" | git mergetool file1 &&
+	yes "" | git mergetool file2 &&
+	yes "" | git mergetool "spaced name" &&
+	yes "" | git mergetool both &&
+	yes "" | git mergetool subdir/file3 &&
+	yes "d" | git mergetool file11 &&
+	yes "d" | git mergetool file12 &&
+	yes "r" | git mergetool submod &&
 	test "$(printf x | cat file1 -)" = "$(printf "master updated\r\nx")" &&
 	test "$(printf x | cat file2 -)" = "$(printf "master new\r\nx")" &&
 	test "$(printf x | cat subdir/file3 -)" = "$(printf "master new sub\r\nx")" &&
 	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git commit -m "branch1 resolved with mergetool - autocrlf"
 '
 
@@ -218,8 +231,9 @@ test_expect_success 'mergetool in subdir' '
 	(
 		cd subdir &&
 		test_must_fail git merge master &&
-		( yes "" | git mergetool file3 ) &&
-		test "$(cat file3)" = "master new sub"
+		yes "" | git mergetool file3 &&
+		echo "master new sub" >expect &&
+		test_cmp expect file3
 	)
 '
 
@@ -230,16 +244,19 @@ test_expect_success 'mergetool on file in parent dir' '
 	(
 		cd subdir &&
 		test_must_fail git merge master &&
-		( yes "" | git mergetool file3 ) &&
-		( yes "" | git mergetool ../file1 ) &&
-		( yes "" | git mergetool ../file2 ../spaced\ name ) &&
-		( yes "" | git mergetool ../both ) &&
-		( yes "d" | git mergetool ../file11 ) &&
-		( yes "d" | git mergetool ../file12 ) &&
-		( yes "l" | git mergetool ../submod ) &&
-		test "$(cat ../file1)" = "master updated" &&
-		test "$(cat ../file2)" = "master new" &&
-		test "$(cat ../submod/bar)" = "branch1 submodule" &&
+		yes "" | git mergetool file3 &&
+		yes "" | git mergetool ../file1 &&
+		yes "" | git mergetool ../file2 ../spaced\ name &&
+		yes "" | git mergetool ../both &&
+		yes "d" | git mergetool ../file11 &&
+		yes "d" | git mergetool ../file12 &&
+		yes "l" | git mergetool ../submod &&
+		echo "master updated" >expect &&
+		test_cmp expect ../file1 &&
+		echo "master new" >expect &&
+		test_cmp expect ../file2 &&
+		echo "branch1 submodule" >expect &&
+		test_cmp expect ../submod/bar &&
 		git commit -m "branch1 resolved with mergetool - subdir"
 	)
 '
@@ -250,9 +267,9 @@ test_expect_success 'mergetool skips autoresolved' '
 	git submodule update -N &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "d" | git mergetool file11 ) &&
-	( yes "d" | git mergetool file12 ) &&
-	( yes "l" | git mergetool submod ) &&
+	yes "d" | git mergetool file11 &&
+	yes "d" | git mergetool file12 &&
+	yes "l" | git mergetool submod &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging"
 '
@@ -264,13 +281,17 @@ test_expect_success 'mergetool merges all from subdir (rerere disabled)' '
 	(
 		cd subdir &&
 		test_must_fail git merge master &&
-		( yes "r" | git mergetool ../submod ) &&
-		( yes "d" "d" | git mergetool --no-prompt ) &&
-		test "$(cat ../file1)" = "master updated" &&
-		test "$(cat ../file2)" = "master new" &&
-		test "$(cat file3)" = "master new sub" &&
+		yes "r" | git mergetool ../submod &&
+		yes "d" "d" | git mergetool --no-prompt &&
+		echo "master updated" >expect &&
+		test_cmp expect ../file1 &&
+		echo "master new" >expect &&
+		test_cmp expect ../file2 &&
+		echo "master new sub" >expect &&
+		test_cmp expect file3 &&
 		( cd .. && git submodule update -N ) &&
-		test "$(cat ../submod/bar)" = "master submodule" &&
+		echo "master submodule" >expect &&
+		test_cmp expect ../submod/bar &&
 		git commit -m "branch2 resolved by mergetool from subdir"
 	)
 '
@@ -283,13 +304,17 @@ test_expect_success 'mergetool merges all from subdir (rerere enabled)' '
 	(
 		cd subdir &&
 		test_must_fail git merge master &&
-		( yes "r" | git mergetool ../submod ) &&
-		( yes "d" "d" | git mergetool --no-prompt ) &&
-		test "$(cat ../file1)" = "master updated" &&
-		test "$(cat ../file2)" = "master new" &&
-		test "$(cat file3)" = "master new sub" &&
+		yes "r" | git mergetool ../submod &&
+		yes "d" "d" | git mergetool --no-prompt &&
+		echo "master updated" >expect &&
+		test_cmp expect ../file1 &&
+		echo "master new" >expect &&
+		test_cmp expect ../file2 &&
+		echo "master new sub" >expect &&
+		test_cmp expect file3 &&
 		( cd .. && git submodule update -N ) &&
-		test "$(cat ../submod/bar)" = "master submodule" &&
+		echo "master submodule" >expect &&
+		test_cmp expect ../submod/bar &&
 		git commit -m "branch2 resolved by mergetool from subdir"
 	)
 '
@@ -301,8 +326,8 @@ test_expect_success 'mergetool skips resolved paths when rerere is active' '
 	git checkout -b test$test_count branch1 &&
 	git submodule update -N &&
 	test_must_fail git merge master &&
-	( yes "l" | git mergetool --no-prompt submod ) &&
-	( yes "d" "d" | git mergetool --no-prompt ) &&
+	yes "l" | git mergetool --no-prompt submod &&
+	yes "d" "d" | git mergetool --no-prompt &&
 	git submodule update -N &&
 	output="$(yes "n" | git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging"
@@ -343,9 +368,10 @@ test_expect_success 'mergetool takes partial path' '
 	git submodule update -N &&
 	test_must_fail git merge master &&
 
-	( yes "" | git mergetool subdir ) &&
+	yes "" | git mergetool subdir &&
 
-	test "$(cat subdir/file3)" = "master new sub"
+	echo "master new sub" >expect &&
+	test_cmp expect subdir/file3
 '
 
 test_expect_success 'mergetool delete/delete conflict' '
@@ -410,14 +436,16 @@ test_expect_success 'deleted vs modified submodule' '
 	git checkout -b test$test_count.a test$test_count &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "r" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "r" | git mergetool submod &&
 	rmdir submod && mv submod-movedaside submod &&
-	test "$(cat submod/bar)" = "branch1 submodule" &&
+	echo "branch1 submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping module" &&
@@ -427,10 +455,10 @@ test_expect_success 'deleted vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "l" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "l" | git mergetool submod &&
 	test ! -e submod &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
@@ -441,10 +469,10 @@ test_expect_success 'deleted vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "r" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "r" | git mergetool submod &&
 	test ! -e submod &&
 	test -d submod.orig &&
 	git submodule update -N &&
@@ -457,13 +485,15 @@ test_expect_success 'deleted vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "l" | git mergetool submod ) &&
-	test "$(cat submod/bar)" = "master submodule" &&
-	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "l" | git mergetool submod &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
+	git submodule update -N &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping module"
@@ -481,14 +511,16 @@ test_expect_success 'file vs modified submodule' '
 	git checkout -b test$test_count.a branch1 &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "r" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "r" | git mergetool submod &&
 	rmdir submod && mv submod-movedaside submod &&
-	test "$(cat submod/bar)" = "branch1 submodule" &&
+	echo "branch1 submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping module" &&
@@ -497,12 +529,13 @@ test_expect_success 'file vs modified submodule' '
 	git checkout -b test$test_count.b test$test_count &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "l" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "l" | git mergetool submod &&
 	git submodule update -N &&
-	test "$(cat submod)" = "not a submodule" &&
+	echo "not a submodule" >expect &&
+	test_cmp expect submod &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping file" &&
@@ -513,13 +546,14 @@ test_expect_success 'file vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "r" | git mergetool submod ) &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "r" | git mergetool submod &&
 	test -d submod.orig &&
 	git submodule update -N &&
-	test "$(cat submod)" = "not a submodule" &&
+	echo "not a submodule" >expect &&
+	test_cmp expect submod &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping file" &&
@@ -529,13 +563,15 @@ test_expect_success 'file vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
-	( yes "" | git mergetool file1 file2 spaced\ name subdir/file3 ) &&
-	( yes "" | git mergetool both ) &&
-	( yes "d" | git mergetool file11 file12 ) &&
-	( yes "l" | git mergetool submod ) &&
-	test "$(cat submod/bar)" = "master submodule" &&
-	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	yes "" | git mergetool file1 file2 spaced\ name subdir/file3 &&
+	yes "" | git mergetool both &&
+	yes "d" | git mergetool file11 file12 &&
+	yes "l" | git mergetool submod &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
+	git submodule update -N &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	output="$(git mergetool --no-prompt)" &&
 	test "$output" = "No files need merging" &&
 	git commit -m "Merge resolved by keeping module"
@@ -587,19 +623,23 @@ test_expect_success 'submodule in subdirectory' '
 	test_must_fail git merge test$test_count.a &&
 	(
 		cd subdir &&
-		( yes "l" | git mergetool subdir_module )
+		yes "l" | git mergetool subdir_module
 	) &&
-	test "$(cat subdir/subdir_module/file15)" = "test$test_count.b" &&
+	echo "test$test_count.b" >expect &&
+	test_cmp expect subdir/subdir_module/file15 &&
 	git submodule update -N &&
-	test "$(cat subdir/subdir_module/file15)" = "test$test_count.b" &&
+	echo "test$test_count.b" >expect &&
+	test_cmp expect subdir/subdir_module/file15 &&
 	git reset --hard &&
 	git submodule update -N &&
 
 	test_must_fail git merge test$test_count.a &&
-	( yes "r" | git mergetool subdir/subdir_module ) &&
-	test "$(cat subdir/subdir_module/file15)" = "test$test_count.b" &&
+	yes "r" | git mergetool subdir/subdir_module &&
+	echo "test$test_count.b" >expect &&
+	test_cmp expect subdir/subdir_module/file15 &&
 	git submodule update -N &&
-	test "$(cat subdir/subdir_module/file15)" = "test$test_count.a" &&
+	echo "test$test_count.a" >expect &&
+	test_cmp expect subdir/subdir_module/file15 &&
 	git commit -m "branch1 resolved with mergetool"
 '
 
@@ -615,22 +655,25 @@ test_expect_success 'directory vs modified submodule' '
 
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
-	( yes "l" | git mergetool submod ) &&
-	test "$(cat submod/file16)" = "not a submodule" &&
+	yes "l" | git mergetool submod &&
+	echo "not a submodule" >expect &&
+	test_cmp expect submod/file16 &&
 	rm -rf submod.orig &&
 
 	git reset --hard &&
 	test_must_fail git merge master &&
 	test -n "$(git ls-files -u)" &&
 	test ! -e submod.orig &&
-	( yes "r" | git mergetool submod ) &&
+	yes "r" | git mergetool submod &&
 	test -d submod.orig &&
-	test "$(cat submod.orig/file16)" = "not a submodule" &&
+	echo "not a submodule" >expect &&
+	test_cmp expect submod.orig/file16 &&
 	rm -r submod.orig &&
 	mv submod-movedaside/.git submod &&
 	( cd submod && git clean -f && git reset --hard ) &&
 	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 	git reset --hard &&
 	rm -rf submod-movedaside &&
 
@@ -638,17 +681,19 @@ test_expect_success 'directory vs modified submodule' '
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
-	( yes "l" | git mergetool submod ) &&
+	yes "l" | git mergetool submod &&
 	git submodule update -N &&
-	test "$(cat submod/bar)" = "master submodule" &&
+	echo "master submodule" >expect &&
+	test_cmp expect submod/bar &&
 
 	git reset --hard &&
 	git submodule update -N &&
 	test_must_fail git merge test$test_count &&
 	test -n "$(git ls-files -u)" &&
 	test ! -e submod.orig &&
-	( yes "r" | git mergetool submod ) &&
-	test "$(cat submod/file16)" = "not a submodule" &&
+	yes "r" | git mergetool submod &&
+	echo "not a submodule" >expect &&
+	test_cmp expect submod/file16 &&
 
 	git reset --hard master &&
 	( cd submod && git clean -f && git reset --hard ) &&
diff --git a/t/t9801-git-p4-branch.sh b/t/t9801-git-p4-branch.sh
index 38d6b9043b..67ff2711f5 100755
--- a/t/t9801-git-p4-branch.sh
+++ b/t/t9801-git-p4-branch.sh
@@ -411,6 +411,46 @@ test_expect_failure 'git p4 clone file subset branch' '
 	)
 '
 
+# Check that excluded files are omitted during import
+test_expect_success 'git p4 clone complex branches with excluded files' '
+	test_when_finished cleanup_git &&
+	test_create_repo "$git" &&
+	(
+		cd "$git" &&
+		git config git-p4.branchList branch1:branch2 &&
+		git config --add git-p4.branchList branch1:branch3 &&
+		git config --add git-p4.branchList branch1:branch4 &&
+		git config --add git-p4.branchList branch1:branch5 &&
+		git config --add git-p4.branchList branch1:branch6 &&
+		git p4 clone --dest=. --detect-branches -//depot/branch1/file2 -//depot/branch2/file2 -//depot/branch3/file2 -//depot/branch4/file2 -//depot/branch5/file2 -//depot/branch6/file2 //depot@all &&
+		git log --all --graph --decorate --stat &&
+		git reset --hard p4/depot/branch1 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_file file3 &&
+		git reset --hard p4/depot/branch2 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_missing file3 &&
+		git reset --hard p4/depot/branch3 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_missing file3 &&
+		git reset --hard p4/depot/branch4 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_file file3 &&
+		git reset --hard p4/depot/branch5 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_file file3 &&
+		git reset --hard p4/depot/branch6 &&
+		test_path_is_file file1 &&
+		test_path_is_missing file2 &&
+		test_path_is_missing file3
+	)
+'
+
 # From a report in http://stackoverflow.com/questions/11893688
 # where --use-client-spec caused branch prefixes not to be removed;
 # every file in git appeared into a subdirectory of the branch name.
@@ -610,4 +650,96 @@ test_expect_success 'Update a file in git side and submit to P4 using client vie
 	)
 '
 
+test_expect_success 'restart p4d (case folding enabled)' '
+	stop_and_cleanup_p4d &&
+	start_p4d -C1
+'
+
+#
+# 1: //depot/main/mf1
+# 2: integrate //depot/main/... -> //depot/branch1/...
+# 3: //depot/main/mf2
+# 4: //depot/BRANCH1/B1f3
+# 5: //depot/branch1/b1f4
+#
+test_expect_success !CASE_INSENSITIVE_FS 'basic p4 branches for case folding' '
+	(
+		cd "$cli" &&
+		mkdir -p main &&
+
+		echo mf1 >main/mf1 &&
+		p4 add main/mf1 &&
+		p4 submit -d "main/mf1" &&
+
+		p4 integrate //depot/main/... //depot/branch1/... &&
+		p4 submit -d "integrate main to branch1" &&
+
+		echo mf2 >main/mf2 &&
+		p4 add main/mf2 &&
+		p4 submit -d "main/mf2" &&
+
+		mkdir BRANCH1 &&
+		echo B1f3 >BRANCH1/B1f3 &&
+		p4 add BRANCH1/B1f3 &&
+		p4 submit -d "BRANCH1/B1f3" &&
+
+		echo b1f4 >branch1/b1f4 &&
+		p4 add branch1/b1f4 &&
+		p4 submit -d "branch1/b1f4"
+	)
+'
+
+# Check that files are properly split across branches when ignorecase is set
+test_expect_success !CASE_INSENSITIVE_FS 'git p4 clone, branchList branch definition, ignorecase' '
+	test_when_finished cleanup_git &&
+	test_create_repo "$git" &&
+	(
+		cd "$git" &&
+		git config git-p4.branchList main:branch1 &&
+		git config --type=bool core.ignoreCase true &&
+		git p4 clone --dest=. --detect-branches //depot@all &&
+
+		git log --all --graph --decorate --stat &&
+
+		git reset --hard p4/master &&
+		test_path_is_file mf1 &&
+		test_path_is_file mf2 &&
+		test_path_is_missing B1f3 &&
+		test_path_is_missing b1f4 &&
+
+		git reset --hard p4/depot/branch1 &&
+		test_path_is_file mf1 &&
+		test_path_is_missing mf2 &&
+		test_path_is_file B1f3 &&
+		test_path_is_file b1f4
+	)
+'
+
+# Check that files are properly split across branches when ignorecase is set, use-client-spec case
+test_expect_success !CASE_INSENSITIVE_FS 'git p4 clone with client-spec, branchList branch definition, ignorecase' '
+	client_view "//depot/... //client/..." &&
+	test_when_finished cleanup_git &&
+	test_create_repo "$git" &&
+	(
+		cd "$git" &&
+		git config git-p4.branchList main:branch1 &&
+		git config --type=bool core.ignoreCase true &&
+		git p4 clone --dest=. --use-client-spec --detect-branches //depot@all &&
+
+		git log --all --graph --decorate --stat &&
+
+		git reset --hard p4/master &&
+		test_path_is_file mf1 &&
+		test_path_is_file mf2 &&
+		test_path_is_missing B1f3 &&
+		test_path_is_missing b1f4 &&
+
+		git reset --hard p4/depot/branch1 &&
+		test_path_is_file mf1 &&
+		test_path_is_missing mf2 &&
+		test_path_is_file B1f3 &&
+		test_path_is_file b1f4
+	)
+'
+
 test_done
diff --git a/t/t9817-git-p4-exclude.sh b/t/t9817-git-p4-exclude.sh
index 96d25f0c02..ec3d937c6a 100755
--- a/t/t9817-git-p4-exclude.sh
+++ b/t/t9817-git-p4-exclude.sh
@@ -22,7 +22,9 @@ test_expect_success 'create exclude repo' '
 		mkdir -p wanted discard &&
 		echo wanted >wanted/foo &&
 		echo discard >discard/foo &&
-		p4 add wanted/foo discard/foo &&
+		echo discard_file >discard_file &&
+		echo discard_file_not >discard_file_not &&
+		p4 add wanted/foo discard/foo discard_file discard_file_not &&
 		p4 submit -d "initial revision"
 	)
 '
@@ -33,7 +35,9 @@ test_expect_success 'check the repo was created correctly' '
 	(
 		cd "$git" &&
 		test_path_is_file wanted/foo &&
-		test_path_is_file discard/foo
+		test_path_is_file discard/foo &&
+		test_path_is_file discard_file &&
+		test_path_is_file discard_file_not
 	)
 '
 
@@ -43,7 +47,21 @@ test_expect_success 'clone, excluding part of repo' '
 	(
 		cd "$git" &&
 		test_path_is_file wanted/foo &&
-		test_path_is_missing discard/foo
+		test_path_is_missing discard/foo &&
+		test_path_is_file discard_file &&
+		test_path_is_file discard_file_not
+	)
+'
+
+test_expect_success 'clone, excluding single file, no trailing /' '
+	test_when_finished cleanup_git &&
+	git p4 clone -//depot/discard_file --dest="$git" //depot/...@all &&
+	(
+		cd "$git" &&
+		test_path_is_file wanted/foo &&
+		test_path_is_file discard/foo &&
+		test_path_is_missing discard_file &&
+		test_path_is_file discard_file_not
 	)
 '
 
@@ -52,15 +70,38 @@ test_expect_success 'clone, then sync with exclude' '
 	git p4 clone -//depot/discard/... --dest="$git" //depot/...@all &&
 	(
 		cd "$cli" &&
-		p4 edit wanted/foo discard/foo &&
+		p4 edit wanted/foo discard/foo discard_file_not &&
 		date >>wanted/foo &&
 		date >>discard/foo &&
+		date >>discard_file_not &&
 		p4 submit -d "updating" &&
 
 		cd "$git" &&
 		git p4 sync -//depot/discard/... &&
 		test_path_is_file wanted/foo &&
-		test_path_is_missing discard/foo
+		test_path_is_missing discard/foo &&
+		test_path_is_file discard_file &&
+		test_path_is_file discard_file_not
+	)
+'
+
+test_expect_success 'clone, then sync with exclude, no trailing /' '
+	test_when_finished cleanup_git &&
+	git p4 clone -//depot/discard/... -//depot/discard_file --dest="$git" //depot/...@all &&
+	(
+		cd "$cli" &&
+		p4 edit wanted/foo discard/foo discard_file_not &&
+		date >>wanted/foo &&
+		date >>discard/foo &&
+		date >>discard_file_not &&
+		p4 submit -d "updating" &&
+
+		cd "$git" &&
+		git p4 sync -//depot/discard/... -//depot/discard_file &&
+		test_path_is_file wanted/foo &&
+		test_path_is_missing discard/foo &&
+		test_path_is_missing discard_file &&
+		test_path_is_file discard_file_not
 	)
 '
 
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index 0367cec5fd..7308f67922 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -908,6 +908,21 @@ test_cmp_rev () {
 	fi
 }
 
+# Compare paths respecting core.ignoreCase
+test_cmp_fspath () {
+	if test "x$1" = "x$2"
+	then
+		return 0
+	fi
+
+	if test true != "$(git config --get --type=bool core.ignorecase)"
+	then
+		return 1
+	fi
+
+	test "x$(echo "$1" | tr A-Z a-z)" =  "x$(echo "$2" | tr A-Z a-z)"
+}
+
 # Print a sequence of integers in increasing order, either with
 # two arguments (start and end):
 #
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 4b346467df..d1ba33745a 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -386,7 +386,6 @@ unset VISUAL EMAIL LANGUAGE COLUMNS $("$PERL_PATH" -e '
 	my @env = keys %ENV;
 	my $ok = join("|", qw(
 		TRACE
-		TR2_
 		DEBUG
 		TEST
 		.*_TEST
diff --git a/tag.c b/tag.c
index 7445b8f6ea..5db870edb9 100644
--- a/tag.c
+++ b/tag.c
@@ -100,10 +100,9 @@ struct object *deref_tag_noverify(struct object *o)
 
 struct tag *lookup_tag(struct repository *r, const struct object_id *oid)
 {
-	struct object *obj = lookup_object(r, oid->hash);
+	struct object *obj = lookup_object(r, oid);
 	if (!obj)
-		return create_object(r, oid->hash,
-				     alloc_tag_node(r));
+		return create_object(r, oid, alloc_tag_node(r));
 	return object_as_type(r, obj, OBJ_TAG, 0);
 }
 
diff --git a/tree.c b/tree.c
index f416afc57d..4720945e6a 100644
--- a/tree.c
+++ b/tree.c
@@ -197,10 +197,9 @@ int read_tree(struct repository *r, struct tree *tree, int stage,
 
 struct tree *lookup_tree(struct repository *r, const struct object_id *oid)
 {
-	struct object *obj = lookup_object(r, oid->hash);
+	struct object *obj = lookup_object(r, oid);
 	if (!obj)
-		return create_object(r, oid->hash,
-				     alloc_tree_node(r));
+		return create_object(r, oid, alloc_tree_node(r));
 	return object_as_type(r, obj, OBJ_TREE, 0);
 }
 
diff --git a/unpack-trees.c b/unpack-trees.c
index 50189909b8..dab713203e 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -315,7 +315,7 @@ static struct progress *get_progress(struct unpack_trees_options *o)
 			total++;
 	}
 
-	return start_delayed_progress(_("Checking out files"), total);
+	return start_delayed_progress(_("Updating files"), total);
 }
 
 static void setup_collided_checkout_detection(struct checkout *state,
diff --git a/upload-pack.c b/upload-pack.c
index 4d2129e7fc..222cd3ad89 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -528,13 +528,13 @@ static int get_reachable_list(struct object_array *src,
 		return -1;
 
 	while ((i = read_in_full(cmd.out, namebuf, hexsz + 1)) == hexsz + 1) {
-		struct object_id sha1;
+		struct object_id oid;
 		const char *p;
 
-		if (parse_oid_hex(namebuf, &sha1, &p) || *p != '\n')
+		if (parse_oid_hex(namebuf, &oid, &p) || *p != '\n')
 			break;
 
-		o = lookup_object(the_repository, sha1.hash);
+		o = lookup_object(the_repository, &oid);
 		if (o && o->type == OBJ_COMMIT) {
 			o->flags &= ~TMP_MARK;
 		}
@@ -722,7 +722,7 @@ static void deepen_by_rev_list(struct packet_writer *writer, int ac,
 {
 	struct commit_list *result;
 
-	close_commit_graph(the_repository);
+	close_commit_graph(the_repository->objects);
 	result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
 	send_shallow(writer, result);
 	free_commit_list(result);
@@ -960,7 +960,7 @@ static void receive_needs(struct packet_reader *reader, struct object_array *wan
 static int mark_our_ref(const char *refname, const char *refname_full,
 			const struct object_id *oid)
 {
-	struct object *o = lookup_unknown_object(oid->hash);
+	struct object *o = lookup_unknown_object(oid);
 
 	if (ref_is_hidden(refname, refname_full)) {
 		o->flags |= HIDDEN_REF;
diff --git a/url.c b/url.c
index 25576c390b..1b8ef78cea 100644
--- a/url.c
+++ b/url.c
@@ -46,9 +46,9 @@ static char *url_decode_internal(const char **query, int len,
 			break;
 		}
 
-		if (c == '%') {
+		if (c == '%' && (len < 0 || len >= 3)) {
 			int val = hex2chr(q + 1);
-			if (0 <= val) {
+			if (0 < val) {
 				strbuf_addch(out, val);
 				q += 3;
 				len -= 3;
diff --git a/userdiff.c b/userdiff.c
index 04270fb4d7..e74a6d4022 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -135,6 +135,12 @@ PATTERNS("ruby", "^[ \t]*((class|module|def)[ \t].*)$",
 	 "(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
 	 "|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
 	 "|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
+PATTERNS("rust",
+	 "^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl)[< \t]+[^;]*)$",
+	 /* -- */
+	 "[a-zA-Z_][a-zA-Z0-9_]*"
+	 "|[0-9][0-9_a-fA-Fiosuxz]*(\\.([0-9]*[eE][+-]?)?[0-9_fF]*)?"
+	 "|[-+*\\/<>%&^|=!:]=|<<=?|>>=?|&&|\\|\\||->|=>|\\.{2}=|\\.{3}|::"),
 PATTERNS("bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
 	 "[={}\"]|[^={}\" \t]+"),
 PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
diff --git a/walker.c b/walker.c
index d74ae59c77..06cd2bd569 100644
--- a/walker.c
+++ b/walker.c
@@ -285,7 +285,7 @@ int walker_fetch(struct walker *walker, int targets, char **target,
 			error("Could not interpret response from server '%s' as something to pull", target[i]);
 			goto done;
 		}
-		if (process(walker, lookup_unknown_object(oids[i].hash)))
+		if (process(walker, lookup_unknown_object(&oids[i])))
 			goto done;
 	}
 
diff --git a/wrapper.c b/wrapper.c
index ea3cf64d4c..1e45ab7b92 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -502,7 +502,7 @@ int git_mkstemps_mode(char *pattern, int suffix_len, int mode)
 	 * Try TMP_MAX different filenames.
 	 */
 	gettimeofday(&tv, NULL);
-	value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid();
+	value = ((uint64_t)tv.tv_usec << 16) ^ tv.tv_sec ^ getpid();
 	filename_template = &pattern[len - 6 - suffix_len];
 	for (count = 0; count < TMP_MAX; ++count) {
 		uint64_t v = value;
diff --git a/wt-status.c b/wt-status.c
index 0bccef542f..7d776f8a97 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -19,6 +19,8 @@
 #include "lockfile.h"
 #include "sequencer.h"
 
+#define AB_DELAY_WARNING_IN_MS (2 * 1000)
+
 static const char cut_line[] =
 "------------------------ >8 ------------------------\n";
 
@@ -179,9 +181,15 @@ static void wt_longstatus_print_unmerged_header(struct wt_status *s)
 		return;
 	if (s->whence != FROM_COMMIT)
 		;
-	else if (!s->is_initial)
-		status_printf_ln(s, c, _("  (use \"git reset %s <file>...\" to unstage)"), s->reference);
-	else
+	else if (!s->is_initial) {
+		if (!strcmp(s->reference, "HEAD"))
+			status_printf_ln(s, c,
+					 _("  (use \"git restore --staged <file>...\" to unstage)"));
+		else
+			status_printf_ln(s, c,
+					 _("  (use \"git restore --source=%s --staged <file>...\" to unstage)"),
+					 s->reference);
+	} else
 		status_printf_ln(s, c, _("  (use \"git rm --cached <file>...\" to unstage)"));
 
 	if (!both_deleted) {
@@ -206,9 +214,15 @@ static void wt_longstatus_print_cached_header(struct wt_status *s)
 		return;
 	if (s->whence != FROM_COMMIT)
 		; /* NEEDSWORK: use "git reset --unresolve"??? */
-	else if (!s->is_initial)
-		status_printf_ln(s, c, _("  (use \"git reset %s <file>...\" to unstage)"), s->reference);
-	else
+	else if (!s->is_initial) {
+		if (!strcmp(s->reference, "HEAD"))
+			status_printf_ln(s, c
+					 , _("  (use \"git restore --staged <file>...\" to unstage)"));
+		else
+			status_printf_ln(s, c,
+					 _("  (use \"git restore --source=%s --staged <file>...\" to unstage)"),
+					 s->reference);
+	} else
 		status_printf_ln(s, c, _("  (use \"git rm --cached <file>...\" to unstage)"));
 	status_printf_ln(s, c, "%s", "");
 }
@@ -226,7 +240,7 @@ static void wt_longstatus_print_dirty_header(struct wt_status *s,
 		status_printf_ln(s, c, _("  (use \"git add <file>...\" to update what will be committed)"));
 	else
 		status_printf_ln(s, c, _("  (use \"git add/rm <file>...\" to update what will be committed)"));
-	status_printf_ln(s, c, _("  (use \"git checkout -- <file>...\" to discard changes in working directory)"));
+	status_printf_ln(s, c, _("  (use \"git restore <file>...\" to discard changes in working directory)"));
 	if (has_dirty_submodules)
 		status_printf_ln(s, c, _("  (commit or discard the untracked or modified content in submodules)"));
 	status_printf_ln(s, c, "%s", "");
@@ -1085,14 +1099,29 @@ static void wt_longstatus_print_tracking(struct wt_status *s)
 	struct branch *branch;
 	char comment_line_string[3];
 	int i;
+	uint64_t t_begin = 0;
 
 	assert(s->branch && !s->is_initial);
 	if (!skip_prefix(s->branch, "refs/heads/", &branch_name))
 		return;
 	branch = branch_get(branch_name);
+
+	t_begin = getnanotime();
+
 	if (!format_tracking_info(branch, &sb, s->ahead_behind_flags))
 		return;
 
+	if (advice_status_ahead_behind_warning &&
+	    s->ahead_behind_flags == AHEAD_BEHIND_FULL) {
+		uint64_t t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
+		if (t_delta_in_ms > AB_DELAY_WARNING_IN_MS) {
+			strbuf_addf(&sb, _("\n"
+					   "It took %.2f seconds to compute the branch ahead/behind values.\n"
+					   "You can use '--no-ahead-behind' to avoid this.\n"),
+				    t_delta_in_ms / 1000.0);
+		}
+	}
+
 	i = 0;
 	if (s->display_comment_prefix) {
 		comment_line_string[i++] = comment_line_char;
@@ -1676,9 +1705,9 @@ static void wt_longstatus_print(struct wt_status *s)
 			} else if (s->state.detached_from) {
 				branch_name = s->state.detached_from;
 				if (s->state.detached_at)
-					on_what = _("HEAD detached at ");
+					on_what = HEAD_DETACHED_AT;
 				else
-					on_what = _("HEAD detached from ");
+					on_what = HEAD_DETACHED_FROM;
 			} else {
 				branch_name = "";
 				on_what = _("Not currently on any branch.");
diff --git a/wt-status.h b/wt-status.h
index 64f1ddc9fd..b0cfdc8011 100644
--- a/wt-status.h
+++ b/wt-status.h
@@ -65,6 +65,9 @@ enum wt_status_format {
 	STATUS_FORMAT_UNSPECIFIED
 };
 
+#define HEAD_DETACHED_AT _("HEAD detached at ")
+#define HEAD_DETACHED_FROM _("HEAD detached from ")
+
 struct wt_status_state {
 	int merge_in_progress;
 	int am_in_progress;