git-bisect.html

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 735 <body class="manpage">
 736 <div id="header">
 737 <h1>
 738 git-bisect(1) Manual Page
 739 </h1>
 740 <h2>NAME</h2>
 741 <div class="sectionbody">
 742 <p>git-bisect -
 743    Use binary search to find the commit that introduced a bug
 744 </p>
 745 </div>
 746 </div>
 747 <div id="content">
 748 <div class="sect1">
 749 <h2 id="_synopsis">SYNOPSIS</h2>
 750 <div class="sectionbody">
 751 <div class="verseblock">
 752 <pre class="content"><em>git bisect</em> &lt;subcommand&gt; &lt;options&gt;</pre>
 753 <div class="attribution">
 754 </div></div>
 755 </div>
 756 </div>
 757 <div class="sect1">
 758 <h2 id="_description">DESCRIPTION</h2>
 759 <div class="sectionbody">
 760 <div class="paragraph"><p>The command takes various subcommands, and different options depending
 761 on the subcommand:</p></div>
 762 <div class="literalblock">
 763 <div class="content">
 764 <pre><code>git bisect start [--term-(new|bad)=&lt;term-new&gt; --term-(old|good)=&lt;term-old&gt;]
 765                  [--no-checkout] [--first-parent] [&lt;bad&gt; [&lt;good&gt;...]] [--] [&lt;paths&gt;...]
 766 git bisect (bad|new|&lt;term-new&gt;) [&lt;rev&gt;]
 767 git bisect (good|old|&lt;term-old&gt;) [&lt;rev&gt;...]
 768 git bisect terms [--term-good | --term-bad]
 769 git bisect skip [(&lt;rev&gt;|&lt;range&gt;)...]
 770 git bisect reset [&lt;commit&gt;]
 771 git bisect (visualize|view)
 772 git bisect replay &lt;logfile&gt;
 773 git bisect log
 774 git bisect run &lt;cmd&gt; [&lt;arg&gt;...]
 775 git bisect help</code></pre>
 776 </div></div>
 777 <div class="paragraph"><p>This command uses a binary search algorithm to find which commit in
 778 your project&#8217;s history introduced a bug. You use it by first telling
 779 it a "bad" commit that is known to contain the bug, and a "good"
 780 commit that is known to be before the bug was introduced. Then <code>git
 781 bisect</code> picks a commit between those two endpoints and asks you
 782 whether the selected commit is "good" or "bad". It continues narrowing
 783 down the range until it finds the exact commit that introduced the
 784 change.</p></div>
 785 <div class="paragraph"><p>In fact, <code>git bisect</code> can be used to find the commit that changed
 786 <strong>any</strong> property of your project; e.g., the commit that fixed a bug, or
 787 the commit that caused a benchmark&#8217;s performance to improve. To
 788 support this more general usage, the terms "old" and "new" can be used
 789 in place of "good" and "bad", or you can choose your own terms. See
 790 section "Alternate terms" below for more information.</p></div>
 791 <div class="sect2">
 792 <h3 id="_basic_bisect_commands_start_bad_good">Basic bisect commands: start, bad, good</h3>
 793 <div class="paragraph"><p>As an example, suppose you are trying to find the commit that broke a
 794 feature that was known to work in version <code>v2.6.13-rc2</code> of your
 795 project. You start a bisect session as follows:</p></div>
 796 <div class="listingblock">
 797 <div class="content">
 798 <pre><code>$ git bisect start
 799 $ git bisect bad                 # Current version is bad
 800 $ git bisect good v2.6.13-rc2    # v2.6.13-rc2 is known to be good</code></pre>
 801 </div></div>
 802 <div class="paragraph"><p>Once you have specified at least one bad and one good commit, <code>git
 803 bisect</code> selects a commit in the middle of that range of history,
 804 checks it out, and outputs something similar to the following:</p></div>
 805 <div class="listingblock">
 806 <div class="content">
 807 <pre><code>Bisecting: 675 revisions left to test after this (roughly 10 steps)</code></pre>
 808 </div></div>
 809 <div class="paragraph"><p>You should now compile the checked-out version and test it. If that
 810 version works correctly, type</p></div>
 811 <div class="listingblock">
 812 <div class="content">
 813 <pre><code>$ git bisect good</code></pre>
 814 </div></div>
 815 <div class="paragraph"><p>If that version is broken, type</p></div>
 816 <div class="listingblock">
 817 <div class="content">
 818 <pre><code>$ git bisect bad</code></pre>
 819 </div></div>
 820 <div class="paragraph"><p>Then <code>git bisect</code> will respond with something like</p></div>
 821 <div class="listingblock">
 822 <div class="content">
 823 <pre><code>Bisecting: 337 revisions left to test after this (roughly 9 steps)</code></pre>
 824 </div></div>
 825 <div class="paragraph"><p>Keep repeating the process: compile the tree, test it, and depending
 826 on whether it is good or bad run <code>git bisect good</code> or <code>git bisect bad</code>
 827 to ask for the next commit that needs testing.</p></div>
 828 <div class="paragraph"><p>Eventually there will be no more revisions left to inspect, and the
 829 command will print out a description of the first bad commit. The
 830 reference <code>refs/bisect/bad</code> will be left pointing at that commit.</p></div>
 831 </div>
 832 <div class="sect2">
 833 <h3 id="_bisect_reset">Bisect reset</h3>
 834 <div class="paragraph"><p>After a bisect session, to clean up the bisection state and return to
 835 the original HEAD, issue the following command:</p></div>
 836 <div class="listingblock">
 837 <div class="content">
 838 <pre><code>$ git bisect reset</code></pre>
 839 </div></div>
 840 <div class="paragraph"><p>By default, this will return your tree to the commit that was checked
 841 out before <code>git bisect start</code>.  (A new <code>git bisect start</code> will also do
 842 that, as it cleans up the old bisection state.)</p></div>
 843 <div class="paragraph"><p>With an optional argument, you can return to a different commit
 844 instead:</p></div>
 845 <div class="listingblock">
 846 <div class="content">
 847 <pre><code>$ git bisect reset &lt;commit&gt;</code></pre>
 848 </div></div>
 849 <div class="paragraph"><p>For example, <code>git bisect reset bisect/bad</code> will check out the first
 850 bad revision, while <code>git bisect reset HEAD</code> will leave you on the
 851 current bisection commit and avoid switching commits at all.</p></div>
 852 </div>
 853 <div class="sect2">
 854 <h3 id="_alternate_terms">Alternate terms</h3>
 855 <div class="paragraph"><p>Sometimes you are not looking for the commit that introduced a
 856 breakage, but rather for a commit that caused a change between some
 857 other "old" state and "new" state. For example, you might be looking
 858 for the commit that introduced a particular fix. Or you might be
 859 looking for the first commit in which the source-code filenames were
 860 finally all converted to your company&#8217;s naming standard. Or whatever.</p></div>
 861 <div class="paragraph"><p>In such cases it can be very confusing to use the terms "good" and
 862 "bad" to refer to "the state before the change" and "the state after
 863 the change". So instead, you can use the terms "old" and "new",
 864 respectively, in place of "good" and "bad". (But note that you cannot
 865 mix "good" and "bad" with "old" and "new" in a single session.)</p></div>
 866 <div class="paragraph"><p>In this more general usage, you provide <code>git bisect</code> with a "new"
 867 commit that has some property and an "old" commit that doesn&#8217;t have that
 868 property. Each time <code>git bisect</code> checks out a commit, you test if that
 869 commit has the property. If it does, mark the commit as "new";
 870 otherwise, mark it as "old". When the bisection is done, <code>git bisect</code>
 871 will report which commit introduced the property.</p></div>
 872 <div class="paragraph"><p>To use "old" and "new" instead of "good" and bad, you must run <code>git
 873 bisect start</code> without commits as argument and then run the following
 874 commands to add the commits:</p></div>
 875 <div class="listingblock">
 876 <div class="content">
 877 <pre><code>git bisect old [&lt;rev&gt;]</code></pre>
 878 </div></div>
 879 <div class="paragraph"><p>to indicate that a commit was before the sought change, or</p></div>
 880 <div class="listingblock">
 881 <div class="content">
 882 <pre><code>git bisect new [&lt;rev&gt;...]</code></pre>
 883 </div></div>
 884 <div class="paragraph"><p>to indicate that it was after.</p></div>
 885 <div class="paragraph"><p>To get a reminder of the currently used terms, use</p></div>
 886 <div class="listingblock">
 887 <div class="content">
 888 <pre><code>git bisect terms</code></pre>
 889 </div></div>
 890 <div class="paragraph"><p>You can get just the old (respectively new) term with <code>git bisect terms
 891 --term-old</code> or <code>git bisect terms --term-good</code>.</p></div>
 892 <div class="paragraph"><p>If you would like to use your own terms instead of "bad"/"good" or
 893 "new"/"old", you can choose any names you like (except existing bisect
 894 subcommands like <code>reset</code>, <code>start</code>, &#8230;) by starting the
 895 bisection using</p></div>
 896 <div class="listingblock">
 897 <div class="content">
 898 <pre><code>git bisect start --term-old &lt;term-old&gt; --term-new &lt;term-new&gt;</code></pre>
 899 </div></div>
 900 <div class="paragraph"><p>For example, if you are looking for a commit that introduced a
 901 performance regression, you might use</p></div>
 902 <div class="listingblock">
 903 <div class="content">
 904 <pre><code>git bisect start --term-old fast --term-new slow</code></pre>
 905 </div></div>
 906 <div class="paragraph"><p>Or if you are looking for the commit that fixed a bug, you might use</p></div>
 907 <div class="listingblock">
 908 <div class="content">
 909 <pre><code>git bisect start --term-new fixed --term-old broken</code></pre>
 910 </div></div>
 911 <div class="paragraph"><p>Then, use <code>git bisect &lt;term-old&gt;</code> and <code>git bisect &lt;term-new&gt;</code> instead
 912 of <code>git bisect good</code> and <code>git bisect bad</code> to mark commits.</p></div>
 913 </div>
 914 <div class="sect2">
 915 <h3 id="_bisect_visualize_view">Bisect visualize/view</h3>
 916 <div class="paragraph"><p>To see the currently remaining suspects in <em>gitk</em>, issue the following
 917 command during the bisection process (the subcommand <code>view</code> can be used
 918 as an alternative to <code>visualize</code>):</p></div>
 919 <div class="listingblock">
 920 <div class="content">
 921 <pre><code>$ git bisect visualize</code></pre>
 922 </div></div>
 923 <div class="paragraph"><p>Git detects a graphical environment through various environment variables:
 924 <code>DISPLAY</code>, which is set in X Window System environments on Unix systems.
 925 <code>SESSIONNAME</code>, which is set under Cygwin in interactive desktop sessions.
 926 <code>MSYSTEM</code>, which is set under Msys2 and Git for Windows.
 927 <code>SECURITYSESSIONID</code>, which may be set on macOS in interactive desktop sessions.</p></div>
 928 <div class="paragraph"><p>If none of these environment variables is set, <em>git log</em> is used instead.
 929 You can also give command-line options such as <code>-p</code> and <code>--stat</code>.</p></div>
 930 <div class="listingblock">
 931 <div class="content">
 932 <pre><code>$ git bisect visualize --stat</code></pre>
 933 </div></div>
 934 </div>
 935 <div class="sect2">
 936 <h3 id="_bisect_log_and_bisect_replay">Bisect log and bisect replay</h3>
 937 <div class="paragraph"><p>After having marked revisions as good or bad, issue the following
 938 command to show what has been done so far:</p></div>
 939 <div class="listingblock">
 940 <div class="content">
 941 <pre><code>$ git bisect log</code></pre>
 942 </div></div>
 943 <div class="paragraph"><p>If you discover that you made a mistake in specifying the status of a
 944 revision, you can save the output of this command to a file, edit it to
 945 remove the incorrect entries, and then issue the following commands to
 946 return to a corrected state:</p></div>
 947 <div class="listingblock">
 948 <div class="content">
 949 <pre><code>$ git bisect reset
 950 $ git bisect replay that-file</code></pre>
 951 </div></div>
 952 </div>
 953 <div class="sect2">
 954 <h3 id="_avoiding_testing_a_commit">Avoiding testing a commit</h3>
 955 <div class="paragraph"><p>If, in the middle of a bisect session, you know that the suggested
 956 revision is not a good one to test (e.g. it fails to build and you
 957 know that the failure does not have anything to do with the bug you
 958 are chasing), you can manually select a nearby commit and test that
 959 one instead.</p></div>
 960 <div class="paragraph"><p>For example:</p></div>
 961 <div class="listingblock">
 962 <div class="content">
 963 <pre><code>$ git bisect good/bad                   # previous round was good or bad.
 964 Bisecting: 337 revisions left to test after this (roughly 9 steps)
 965 $ git bisect visualize                  # oops, that is uninteresting.
 966 $ git reset --hard HEAD~3               # try 3 revisions before what
 967                                         # was suggested</code></pre>
 968 </div></div>
 969 <div class="paragraph"><p>Then compile and test the chosen revision, and afterwards mark
 970 the revision as good or bad in the usual manner.</p></div>
 971 </div>
 972 <div class="sect2">
 973 <h3 id="_bisect_skip">Bisect skip</h3>
 974 <div class="paragraph"><p>Instead of choosing a nearby commit by yourself, you can ask Git to do
 975 it for you by issuing the command:</p></div>
 976 <div class="listingblock">
 977 <div class="content">
 978 <pre><code>$ git bisect skip                 # Current version cannot be tested</code></pre>
 979 </div></div>
 980 <div class="paragraph"><p>However, if you skip a commit adjacent to the one you are looking for,
 981 Git will be unable to tell exactly which of those commits was the
 982 first bad one.</p></div>
 983 <div class="paragraph"><p>You can also skip a range of commits, instead of just one commit,
 984 using range notation. For example:</p></div>
 985 <div class="listingblock">
 986 <div class="content">
 987 <pre><code>$ git bisect skip v2.5..v2.6</code></pre>
 988 </div></div>
 989 <div class="paragraph"><p>This tells the bisect process that no commit after <code>v2.5</code>, up to and
 990 including <code>v2.6</code>, should be tested.</p></div>
 991 <div class="paragraph"><p>Note that if you also want to skip the first commit of the range you
 992 would issue the command:</p></div>
 993 <div class="listingblock">
 994 <div class="content">
 995 <pre><code>$ git bisect skip v2.5 v2.5..v2.6</code></pre>
 996 </div></div>
 997 <div class="paragraph"><p>This tells the bisect process that the commits between <code>v2.5</code> and
 998 <code>v2.6</code> (inclusive) should be skipped.</p></div>
 999 </div>
1000 <div class="sect2">
1001 <h3 id="_cutting_down_bisection_by_giving_more_parameters_to_bisect_start">Cutting down bisection by giving more parameters to bisect start</h3>
1002 <div class="paragraph"><p>You can further cut down the number of trials, if you know what part of
1003 the tree is involved in the problem you are tracking down, by specifying
1004 path parameters when issuing the <code>bisect start</code> command:</p></div>
1005 <div class="listingblock">
1006 <div class="content">
1007 <pre><code>$ git bisect start -- arch/i386 include/asm-i386</code></pre>
1008 </div></div>
1009 <div class="paragraph"><p>If you know beforehand more than one good commit, you can narrow the
1010 bisect space down by specifying all of the good commits immediately after
1011 the bad commit when issuing the <code>bisect start</code> command:</p></div>
1012 <div class="listingblock">
1013 <div class="content">
1014 <pre><code>$ git bisect start v2.6.20-rc6 v2.6.20-rc4 v2.6.20-rc1 --
1015                    # v2.6.20-rc6 is bad
1016                    # v2.6.20-rc4 and v2.6.20-rc1 are good</code></pre>
1017 </div></div>
1018 </div>
1019 <div class="sect2">
1020 <h3 id="_bisect_run">Bisect run</h3>
1021 <div class="paragraph"><p>If you have a script that can tell if the current source code is good
1022 or bad, you can bisect by issuing the command:</p></div>
1023 <div class="listingblock">
1024 <div class="content">
1025 <pre><code>$ git bisect run my_script arguments</code></pre>
1026 </div></div>
1027 <div class="paragraph"><p>Note that the script (<code>my_script</code> in the above example) should exit
1028 with code 0 if the current source code is good/old, and exit with a
1029 code between 1 and 127 (inclusive), except 125, if the current source
1030 code is bad/new.</p></div>
1031 <div class="paragraph"><p>Any other exit code will abort the bisect process. It should be noted
1032 that a program that terminates via <code>exit(-1)</code> leaves $? = 255, (see the
1033 exit(3) manual page), as the value is chopped with <code>&amp; 0377</code>.</p></div>
1034 <div class="paragraph"><p>The special exit code 125 should be used when the current source code
1035 cannot be tested. If the script exits with this code, the current
1036 revision will be skipped (see <code>git bisect skip</code> above). 125 was chosen
1037 as the highest sensible value to use for this purpose, because 126 and 127
1038 are used by POSIX shells to signal specific error status (127 is for
1039 command not found, 126 is for command found but not executable&#8212;these
1040 details do not matter, as they are normal errors in the script, as far as
1041 <code>bisect run</code> is concerned).</p></div>
1042 <div class="paragraph"><p>You may often find that during a bisect session you want to have
1043 temporary modifications (e.g. s/#define DEBUG 0/#define DEBUG 1/ in a
1044 header file, or "revision that does not have this commit needs this
1045 patch applied to work around another problem this bisection is not
1046 interested in") applied to the revision being tested.</p></div>
1047 <div class="paragraph"><p>To cope with such a situation, after the inner <em>git bisect</em> finds the
1048 next revision to test, the script can apply the patch
1049 before compiling, run the real test, and afterwards decide if the
1050 revision (possibly with the needed patch) passed the test and then
1051 rewind the tree to the pristine state.  Finally the script should exit
1052 with the status of the real test to let the <code>git bisect run</code> command loop
1053 determine the eventual outcome of the bisect session.</p></div>
1054 </div>
1055 </div>
1056 </div>
1057 <div class="sect1">
1058 <h2 id="_options">OPTIONS</h2>
1059 <div class="sectionbody">
1060 <div class="dlist"><dl>
1061 <dt class="hdlist1">
1062 --no-checkout
1063 </dt>
1064 <dd>
1065 <div class="paragraph"><p>Do not checkout the new working tree at each iteration of the bisection
1066 process. Instead just update the reference named <code>BISECT_HEAD</code> to make
1067 it point to the commit that should be tested.</p></div>
1068 <div class="paragraph"><p>This option may be useful when the test you would perform in each step
1069 does not require a checked out tree.</p></div>
1070 <div class="paragraph"><p>If the repository is bare, <code>--no-checkout</code> is assumed.</p></div>
1071 </dd>
1072 <dt class="hdlist1">
1073 --first-parent
1074 </dt>
1075 <dd>
1076 <div class="paragraph"><p>Follow only the first parent commit upon seeing a merge commit.</p></div>
1077 <div class="paragraph"><p>In detecting regressions introduced through the merging of a branch, the merge
1078 commit will be identified as introduction of the bug and its ancestors will be
1079 ignored.</p></div>
1080 <div class="paragraph"><p>This option is particularly useful in avoiding false positives when a merged
1081 branch contained broken or non-buildable commits, but the merge itself was OK.</p></div>
1082 </dd>
1083 </dl></div>
1084 </div>
1085 </div>
1086 <div class="sect1">
1087 <h2 id="_examples">EXAMPLES</h2>
1088 <div class="sectionbody">
1089 <div class="ulist"><ul>
1090 <li>
1091 <p>
1092 Automatically bisect a broken build between v1.2 and HEAD:
1093 </p>
1094 <div class="listingblock">
1095 <div class="content">
1096 <pre><code>$ git bisect start HEAD v1.2 --      # HEAD is bad, v1.2 is good
1097 $ git bisect run make                # "make" builds the app
1098 $ git bisect reset                   # quit the bisect session</code></pre>
1099 </div></div>
1100 </li>
1101 <li>
1102 <p>
1103 Automatically bisect a test failure between origin and HEAD:
1104 </p>
1105 <div class="listingblock">
1106 <div class="content">
1107 <pre><code>$ git bisect start HEAD origin --    # HEAD is bad, origin is good
1108 $ git bisect run make test           # "make test" builds and tests
1109 $ git bisect reset                   # quit the bisect session</code></pre>
1110 </div></div>
1111 </li>
1112 <li>
1113 <p>
1114 Automatically bisect a broken test case:
1115 </p>
1116 <div class="listingblock">
1117 <div class="content">
1118 <pre><code>$ cat ~/test.sh
1119 #!/bin/sh
1120 make || exit 125                     # this skips broken builds
1121 ~/check_test_case.sh                 # does the test case pass?
1122 $ git bisect start HEAD HEAD~10 --   # culprit is among the last 10
1123 $ git bisect run ~/test.sh
1124 $ git bisect reset                   # quit the bisect session</code></pre>
1125 </div></div>
1126 <div class="paragraph"><p>Here we use a <code>test.sh</code> custom script. In this script, if <code>make</code>
1127 fails, we skip the current commit.
1128 <code>check_test_case.sh</code> should <code>exit 0</code> if the test case passes,
1129 and <code>exit 1</code> otherwise.</p></div>
1130 <div class="paragraph"><p>It is safer if both <code>test.sh</code> and <code>check_test_case.sh</code> are
1131 outside the repository to prevent interactions between the bisect,
1132 make and test processes and the scripts.</p></div>
1133 </li>
1134 <li>
1135 <p>
1136 Automatically bisect with temporary modifications (hot-fix):
1137 </p>
1138 <div class="listingblock">
1139 <div class="content">
1140 <pre><code>$ cat ~/test.sh
1141 #!/bin/sh
1142
1143 # tweak the working tree by merging the hot-fix branch
1144 # and then attempt a build
1145 if      git merge --no-commit --no-ff hot-fix &amp;&amp;
1146         make
1147 then
1148         # run project specific test and report its status
1149         ~/check_test_case.sh
1150         status=$?
1151 else
1152         # tell the caller this is untestable
1153         status=125
1154 fi
1155
1156 # undo the tweak to allow clean flipping to the next commit
1157 git reset --hard
1158
1159 # return control
1160 exit $status</code></pre>
1161 </div></div>
1162 <div class="paragraph"><p>This applies modifications from a hot-fix branch before each test run,
1163 e.g. in case your build or test environment changed so that older
1164 revisions may need a fix which newer ones have already. (Make sure the
1165 hot-fix branch is based off a commit which is contained in all revisions
1166 which you are bisecting, so that the merge does not pull in too much, or
1167 use <code>git cherry-pick</code> instead of <code>git merge</code>.)</p></div>
1168 </li>
1169 <li>
1170 <p>
1171 Automatically bisect a broken test case:
1172 </p>
1173 <div class="listingblock">
1174 <div class="content">
1175 <pre><code>$ git bisect start HEAD HEAD~10 --   # culprit is among the last 10
1176 $ git bisect run sh -c "make || exit 125; ~/check_test_case.sh"
1177 $ git bisect reset                   # quit the bisect session</code></pre>
1178 </div></div>
1179 <div class="paragraph"><p>This shows that you can do without a run script if you write the test
1180 on a single line.</p></div>
1181 </li>
1182 <li>
1183 <p>
1184 Locate a good region of the object graph in a damaged repository
1185 </p>
1186 <div class="listingblock">
1187 <div class="content">
1188 <pre><code>$ git bisect start HEAD &lt;known-good-commit&gt; [ &lt;boundary-commit&gt; ... ] --no-checkout
1189 $ git bisect run sh -c '
1190         GOOD=$(git for-each-ref "--format=%(objectname)" refs/bisect/good-*) &amp;&amp;
1191         git rev-list --objects BISECT_HEAD --not $GOOD &gt;tmp.$$ &amp;&amp;
1192         git pack-objects --stdout &gt;/dev/null &lt;tmp.$$
1193         rc=$?
1194         rm -f tmp.$$
1195         test $rc = 0'
1196
1197 $ git bisect reset                   # quit the bisect session</code></pre>
1198 </div></div>
1199 <div class="paragraph"><p>In this case, when <em>git bisect run</em> finishes, bisect/bad will refer to a commit that
1200 has at least one parent whose reachable graph is fully traversable in the sense
1201 required by <em>git pack objects</em>.</p></div>
1202 </li>
1203 <li>
1204 <p>
1205 Look for a fix instead of a regression in the code
1206 </p>
1207 <div class="listingblock">
1208 <div class="content">
1209 <pre><code>$ git bisect start
1210 $ git bisect new HEAD    # current commit is marked as new
1211 $ git bisect old HEAD~10 # the tenth commit from now is marked as old</code></pre>
1212 </div></div>
1213 <div class="paragraph"><p>or:</p></div>
1214 </li>
1215 </ul></div>
1216 <div class="listingblock">
1217 <div class="content">
1218 <pre><code>$ git bisect start --term-old broken --term-new fixed
1219 $ git bisect fixed
1220 $ git bisect broken HEAD~10</code></pre>
1221 </div></div>
1222 <div class="sect2">
1223 <h3 id="_getting_help">Getting help</h3>
1224 <div class="paragraph"><p>Use <code>git bisect</code> to get a short usage description, and <code>git bisect
1225 help</code> or <code>git bisect -h</code> to get a long usage description.</p></div>
1226 </div>
1227 </div>
1228 </div>
1229 <div class="sect1">
1230 <h2 id="_see_also">SEE ALSO</h2>
1231 <div class="sectionbody">
1232 <div class="paragraph"><p><a href="git-bisect-lk2009.html">Fighting regressions with git bisect</a>,
1233 <a href="git-blame.html">git-blame(1)</a>.</p></div>
1234 </div>
1235 </div>
1236 <div class="sect1">
1237 <h2 id="_git">GIT</h2>
1238 <div class="sectionbody">
1239 <div class="paragraph"><p>Part of the <a href="git.html">git(1)</a> suite</p></div>
1240 </div>
1241 </div>
1242 </div>
1243 <div id="footnotes"><hr /></div>
1244 <div id="footer">
1245 <div id="footer-text">
1246 Last updated
1247  2023-12-27 15:50:18 PST
1248 </div>
1249 </div>
1250 </body>
1251 </html>