SYNOPSIS
--------
-'git bisect' <subcommand> <options>
+'git bisect' <subcommand> <options>
DESCRIPTION
-----------
The command takes various subcommands, and different options depending
on the subcommand:
- git bisect start [<paths>...]
- git bisect bad <rev>
- git bisect good <rev>
+ git bisect help
+ git bisect start [<bad> [<good>...]] [--] [<paths>...]
+ git bisect bad [<rev>]
+ git bisect good [<rev>...]
+ git bisect skip [<rev>...]
git bisect reset [<branch>]
git bisect visualize
git bisect replay <logfile>
binary search process to find which change introduced a bug, given an
old "good" commit object name and a later "bad" commit object name.
+Getting help
+~~~~~~~~~~~~
+
+Use "git bisect" to get a short usage description, and "git bisect
+help" or "git bisect -h" to get a long usage description.
+
+Basic bisect commands: start, bad, good
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
The way you use it is:
------------------------------------------------
$ git bisect start
-$ git bisect bad # Current version is bad
-$ git bisect good v2.6.13-rc2 # v2.6.13-rc2 was the last version
- # tested that was good
+$ git bisect bad # Current version is bad
+$ git bisect good v2.6.13-rc2 # v2.6.13-rc2 was the last version
+ # tested that was good
------------------------------------------------
When you give at least one bad and one good versions, it will bisect
Until you have no more left, and you'll have been left with the first
bad kernel rev in "refs/bisect/bad".
+Bisect reset
+~~~~~~~~~~~~
+
Oh, and then after you want to reset to the original head, do a
------------------------------------------------
actually: it will reset the bisection state, and before it does that
it checks that you're not using some old bisection branch).
+Bisect visualize
+~~~~~~~~~~~~~~~~
+
During the bisection process, you can say
------------
$ git bisect visualize
------------
-to see the currently remaining suspects in `gitk`.
+to see the currently remaining suspects in `gitk`. `visualize` is a bit
+too long to type and `view` is provided as a synonym.
+
+If `DISPLAY` environment variable is not set, `git log` is used
+instead. You can even give command line options such as `-p` and
+`--stat`.
+
+------------
+$ git bisect view --stat
+------------
+
+Bisect log and bisect replay
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The good/bad input is logged, and
if you find later you made a mistake telling good/bad about a
revision.
+Avoiding to test a commit
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
If in a middle of bisect session, you know what the bisect suggested
to try next is not a good one to test (e.g. the change the commit
introduces is known not to work in your environment and you know it
Then compile and test the one you chose to try. After that, tell
bisect what the result was as usual.
+Bisect skip
+~~~~~~~~~~~~
+
+Instead of choosing by yourself a nearby commit, you may just want git
+to do it for you using:
+
+------------
+$ git bisect skip # Current version cannot be tested
+------------
+
+But computing the commit to test may be slower afterwards and git may
+eventually not be able to tell the first bad among a bad and one or
+more "skip"ped commits.
+
+Cutting down bisection by giving more parameters to bisect start
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
You can further cut down the number of trials if you know what part of
the tree is involved in the problem you are tracking down, by giving
paths parameters when you say `bisect start`, like this:
------------
-$ git bisect start arch/i386 include/asm-i386
+$ git bisect start -- arch/i386 include/asm-i386
+------------
+
+If you know beforehand more than one good commits, you can narrow the
+bisect space down without doing the whole tree checkout every time you
+give good commits. You give the bad revision immediately after `start`
+and then you give all the good revisions you have:
+
+------------
+$ git bisect start v2.6.20-rc6 v2.6.20-rc4 v2.6.20-rc1 --
+ # v2.6.20-rc6 is bad
+ # v2.6.20-rc4 and v2.6.20-rc1 are good
------------
+Bisect run
+~~~~~~~~~~
+
If you have a script that can tell if the current source code is good
or bad, you can automatically bisect using:
------------
Note that the "run" script (`my_script` in the above example) should
-exit with code 0 in case the current source code is good and with a
-code between 1 and 127 (included) in case the current source code is
-bad.
+exit with code 0 in case the current source code is good. Exit with a
+code between 1 and 127 (inclusive), except 125, if the current
+source code is bad.
Any other exit code will abort the automatic bisect process. (A
program that does "exit(-1)" leaves $? = 255, see exit(3) manual page,
the value is chopped with "& 0377".)
+The special exit code 125 should be used when the current source code
+cannot be tested. If the "run" script exits with this code, the current
+revision will be skipped, see `git bisect skip` above.
+
You may often find that during bisect you want to have near-constant
tweaks (e.g., s/#define DEBUG 0/#define DEBUG 1/ in a header file, or
"revision that does not have this commit needs this patch applied to
GIT
---
-Part of the gitlink:git[7] suite
-
+Part of the linkgit:git[7] suite