Merge branch 'jn/gc-auto'

"gc --auto" ended up calling exit(-1) upon error, which has been
corrected to use exit(1).  Also the error reporting behaviour when
daemonized has been updated to exit with zero status when stopping
due to a previously discovered error (which implies there is no
point running gc to improve the situation); we used to exit with
failure in such a case.

* jn/gc-auto:
gc: do not return error for prior errors in daemonized mode

diff --cc Documentation/config.txt
index c9f8b72df7a59ab01dc800e96c2e26bf9ca33e96,5b72684999fafe224ed5c4185b36a90edc4ac31c..7d58253368ce5eed36d6ccf2d757c87a1343fc5b
--- 1/Documentation/config.txt
--- 2/Documentation/config.txt
+++ b/Documentation/config.txt
@@@ -1635,15 -1647,9 +1635,16 @@@ this configuration variable is ignored
  will be repacked. After this the number of packs should go below
  gc.autoPackLimit and gc.bigPackThreshold should be respected again.
  
 +gc.writeCommitGraph::
 +      If true, then gc will rewrite the commit-graph file when
 +      linkgit:git-gc[1] is run. When using linkgit:git-gc[1]
 +      '--auto' the commit-graph will be updated if housekeeping is
 +      required. Default is false. See linkgit:git-commit-graph[1]
 +      for details.
 +
  gc.logExpiry::
-       If the file gc.log exists, then `git gc --auto` won't run
+       If the file gc.log exists, then `git gc --auto` will print
+       its content and exit with status zero instead of running
        unless that file is more than 'gc.logExpiry' old.  Default is
        "1.day".  See `gc.pruneExpire` for more ways to specify its
        value.

diff --cc builtin/gc.c
Simple merge

diff --cc t/t6500-gc.sh
Simple merge