.\" It was generated using the DocBook XSL Stylesheets (version 1.69.1).
.\" Instead of manually editing it, you probably should edit the DocBook XML
.\" source for it and then use the DocBook XSL Stylesheets to regenerate it.
-.TH "GIT\-BISECT" "1" "03/23/2007" "" ""
+.TH "GIT\-BISECT" "1" "03/24/2007" "" ""
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
git bisect run <cmd>...
.fi
This command uses \fIgit\-rev\-list \-\-bisect\fR option to help drive the binary search process to find which change introduced a bug, given an old "good" commit object name and a later "bad" commit object name.
-
+.SS "Basic bisect commands: start, bad, good"
The way you use it is:
.sp
.nf
$ 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
.fi
When you give at least one bad and one good versions, it will bisect the revision tree and say something like:
.sp
and you continue along, compiling that one, testing it, and depending on whether it is good or bad, you say "git bisect good" or "git bisect bad", and ask for the next bisection.
Until you have no more left, and you'll have been left with the first bad kernel rev in "refs/bisect/bad".
-
+.SS "Bisect reset"
Oh, and then after you want to reset to the original head, do a
.sp
.nf
$ git bisect reset
.fi
to get back to the master branch, instead of being in one of the bisection branches ("git bisect start" will do that for you too, actually: it will reset the bisection state, and before it does that it checks that you're not using some old bisection branch).
-
+.SS "Bisect visualize"
During the bisection process, you can say
.sp
.nf
$ git bisect visualize
.fi
to see the currently remaining suspects in gitk.
-
-The good/bad input is logged, and git bisect log shows what you have done so far. You can truncate its output somewhere and save it in a file, and run
+.SS "Bisect log and bisect replay"
+The good/bad input is logged, and
+.sp
+.nf
+$ git bisect log
+.fi
+shows what you have done so far. You can truncate its output somewhere and save it in a file, and run
.sp
.nf
$ git bisect replay that\-file
.fi
if you find later you made a mistake telling good/bad about a revision.
+.SS "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 does not have anything to do with the bug you are chasing), you may want to find a near\-by commit and try that instead.
-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 does not have anything to do with the bug you are chasing), you may want to find a near\-by commit and try that instead. It goes something like this:
+It goes something like this:
.sp
.nf
$ git bisect good/bad # previous round was good/bad.
# was suggested
.fi
Then compile and test the one you chose to try. After that, tell bisect what the result was as usual.
-
+.SS "Cutting down bisection by giving path parameter 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:
.sp
.nf
$ git bisect start arch/i386 include/asm\-i386
.fi
+.SS "Bisect run"
If you have a script that can tell if the current source code is good or bad, you can automatically bisect using:
.sp
.nf
.fi
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.
-Any other exit code (a program that does "exit(\-1)" leaves $? = 255, see exit(3) manual page, the value is chopped with "& 0377") will abort the automatic bisect process.
+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".)
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 work around other problem this bisection is not interested in") applied to the revision being tested.
projects / git.git / commitdiff