[PATCH] name-rev: fix an 'may be used uninitialized' error

From: Ramsay Jones <ramsay@ramsayjones.plus.com>
Date: May 3, 2026, 15:16 UTC
Message-ID: <e74a8fd8-0617-46a8-8bef-a454d51a99c1@ramsayjones.plus.com>

Today's seen branch fails to build (with DEVELOPER=1), like so:

      CC builtin/name-rev.o
  builtin/name-rev.c: In function ‘cmd_format_rev’:
  builtin/name-rev.c:885:28: error: ‘commit’ may be used uninitialized [-Werror=maybe-uninitialized]
    885 |                         if (!commit) {
        |                            ^
  builtin/name-rev.c:867:40: note: ‘commit’ was declared here
    867 |                         struct commit *commit;
        |                                        ^~~~~~
  cc1: all warnings being treated as errors
  make: *** [Makefile:2932: builtin/name-rev.o] Error 1

This can be fixed in several ways; initialise the 'commit' variable to NULL (on line 867), initialise 'commit' to NULL on the line before the conditional on line 883, or (as I chose here) initialise the 'commit' variable in an else arm of the conditional.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---

Hi Kristoffer,

I wrote this patch yesterday, just before I had to go out, and didn't get around to sending it to the list. Today, the problem has gone away ... (along with the 'kh/name-rev-custom-format' branch)!

Assuming you will be sending a new version soon, ... could you please squash this (or similar) into the patch corresponding to commit 5903855b1c ("format-rev: introduce builtin for on-demand pretty formatting", 2026-04-29).

Note that I don't think this particular fix is better than any other, it was just that my cursor was on that line in vim ... :)

ATB, Ramsay Jones

 builtin/name-rev.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index b941e93834..5b7f7a00e5 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -882,6 +882,8 @@ int cmd_format_rev(int argc,
 			peeled = deref_tag(the_repository, object, scratch_buf.buf, 0);
 			if (peeled && peeled->type == OBJ_COMMIT)
 				commit = (struct commit *)peeled;
+			else
+				commit = NULL;
 			if (!commit) {
 				fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 					*argv);

-- 
2.54.0