Re: [BUG] v2.16.0-rc0 seg faults when git bisect skip
- Date: Sat, 6 Jan 2018 09:21:16 +0100
- From: Martin Ågren <martin.agren@xxxxxxxxx>
- Subject: Re: [BUG] v2.16.0-rc0 seg faults when git bisect skip
> On Fri, Jan 5, 2018 at 11:45 AM, Yasushi SHOJI <yasushi.shoji@xxxxxxxxx> wrote:
>> When does the list allowed to contain NULLs?
Short answer: there are no commits left to test.
The list is built in the for-loop in `find_bisection()`. So the
technical answer is: if all commits in the initial list `commit_list`
are UNINTERESTING (including if `commit_list` is empty to begin with).
It's also helpful to study where we should end up from there. We should
take the `if (!revs.commits)` branch in `bisect_next_all()`. That is, we
should print either "There are only 'skip'ped commits left to test. The
first bad commit could be any of:" or "<commit> was both good and bad".
>> Since nobody noticed it since 7c117184d7, it must be a rare case, right?
Right, you marked a commit both good and bad. That's probably not very
common. But it obviously happens. :-)
On 5 January 2018 at 06:28, Yasushi SHOJI <yasushi.shoji@xxxxxxxxx> wrote:
> OK, here is the step to reproduce on git.git
Thank you for providing a script for reproducing this. It helped me come
up with the attached patch. The patch is based on ma/bisect-leakfix,
which includes Ævar's patch.
I think this patch could be useful, either as a final "let's test
something previously non-tested; this would have caught the segfault",
or simply squashed into Ævar's patch as a "let's add a test that would
have caught this, and which also tests a previously non-tested code
Thanks for digging and finding a reproduction recipe.
-- >8 --
Subject: [PATCH] bisect: add test for marking commit both good and bad
Since 670f5fe34f ([PATCH] Fix bisection terminating condition,
2005-08-30), we have noticed and complained when a commit was marked
both good and bad. But we had no tests for this behavior.
Test the behavior when we mark a commit first bad, then good, but also
when we are already in the bad state, where `git bisect skip` should
This test would have caught the segfault which was recently fixed in
2e9fdc795c (bisect: fix a regression causing a segfault, 2018-01-03).
Signed-off-by: Martin Ågren <martin.agren@xxxxxxxxx>
t/t6030-bisect-porcelain.sh | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index 8c2c6eaef8..190f0ce0ab 100755
@@ -894,4 +894,13 @@ test_expect_success 'bisect start takes options and revs in any order' '
test_cmp expected actual
+test_expect_success 'marking commit both good and bad gets reported' '
+ git bisect reset &&
+ git bisect start HEAD &&
+ test_must_fail git bisect good HEAD >out &&
+ test_i18ngrep "both good and bad" out &&
+ test_must_fail git bisect skip >out &&
+ test_i18ngrep "both good and bad" out