From: rsbecker@nexbridge.com
Date: Wed, 22 Oct 2025 14:27:01 GMT
Subject: RE: [BUG] Strange git notes completion behaviour
Message-ID: <018701dc435f$f1dc1a00$d5944e00$@nexbridge.com>
In-Reply-To: <20251022092708.GE853931@coredump.intra.peff.net>

On October 22, 2025 5:27 AM, Jeff King wrote:
>On Tue, Oct 21, 2025 at 05:52:38PM -0400, rsbecker@nexbridge.com wrote:
>
>> It is the exit code. When in gdb, the return from notes is -12 as
>> above. By the time It gets back to bash, the lower bytes are dropped
>> so I end up with a 0xFF, which bash thinks is a 0, so the exit code is
>> hidden from view. I tried the !!fn construct in a standard alone test program with
>no wisdom gained.
>
>I don't think the "!!fn()" line ever returns here. In the show() function of
>builtin/notes.c (which is what "fn" is pointing to for "git notes show"), we end up
>calling execv_git_cmd() to run "git show". So you are really seeing the exit code of
>something like:
>
>  git show $(git notes list HEAD)
>
>That in turn is propagating the return from show_blob_object(). Which I'd think
>would return "0" here, since it actually showed the blob, though it does look like it
>could return -1 in a few cases.
>
>Another possible point of confusion: that git-show invocation will run a pager. It's
>been a long time since I've looked at that code, but IIRC we try to preserve the exit
>code of the actual Git command (rather than the pager). But you might try:
>
>  git --no-pager notes show HEAD
>
>to see if that behaves differently. I couldn't reproduce the issue at all on my end.

I tried running with --no-pager. No difference. Interesting:

git show $(git notes list HEAD)

works correctly with no error report (from inside gdb), while the run of

git --no-pager notes show HEAD

still reports:
Run till exit from #0  main (argc=5, argv=0x811d000)
    at /home/jenkinsbuild/.jenkins/workspace/Git_Pipeline/common-main.c:8
Process (0,896) exited with code 037777777764.

Is there a path where just an implied return is used? I have seen the optimizer
return whatever is in an x86 register - rsx and rsi are both 12 at git.c:982
- on occasion.