'seen' branch fails to build

From: Ramsay Jones <ramsay@ramsayjones.plus.com>
Date: Aug 9, 2025, 13:34 UTC
Message-ID: <92c8c9eb-91de-48c6-88ac-7d5583cc766a@ramsayjones.plus.com>

Hi Junio,

You have probably already fixed this but, just in case you are unaware, the current 'seen' branch @9faf989da6 ("Merge branch 'gh/git-jump-pathname-with-sp' into seen", 2025-08-08) fails to build for me with DEVELOPER=1:

      CC builtin/diff.o
  builtin/diff.c: In function ‘cmd_diff’:
  builtin/diff.c:500:17: error: ignoring return value of ‘chdir’ declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
    500 |                 chdir(prefix);
        |                 ^~~~~~~~~~~~~
  cc1: all warnings being treated as errors
  make: *** [Makefile:2818: builtin/diff.o] Error 1

See commit 456a265746 ("diff: --no-index should ignore the worktree", 2025-08-07) in the 'jc/diff-no-index-in-subdir' branch.

In order to get it to build, I just did:

  $ git diff
  diff --git a/builtin/diff.c b/builtin/diff.c
  index 3eb4cbb057..ff16d7be99 100644
  --- a/builtin/diff.c
  +++ b/builtin/diff.c
  @@ -497,7 +497,8 @@ int cmd_diff(int argc,
           * prefix.
           */
          if (no_index && prefix) {
  -               chdir(prefix);
  +               if (chdir(prefix) < 0)
  +                       die_errno(_("cannot chdir to %s"), prefix);
                  prefix = NULL;
          }
   
  $

[I don't know if that is the best solution; it was just the quickest! :) ]

ATB, Ramsay Jones