object_array: use `object_array_clear()`, not `free()`

Instead of freeing `foo.objects` for an object array `foo` (sometimes
conditionally), call `object_array_clear(&foo)`. This means we don't
poke as much into the implementation, which is already a good thing, but
also that we release the individual entries as well, thereby fixing at
least one memory-leak (in diff-lib.c).

If someone is holding on to a pointer to an element's `name` or `path`,
that is now a dangling pointer, i.e., we'd be turning an unpleasant
situation into an outright bug. To the best of my understanding no such
long-term pointers are being taken.

The way we handle `study` in builting/reflog.c still looks like it might
leak. That will be addressed in the next commit.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/submodule.c b/submodule.c
index 36f45f5..79fd01f 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1728,7 +1728,7 @@ static int find_first_merges(struct object_array *result, const char *path,
 			add_object_array(merges.objects[i].item, NULL, result);
 	}
 
-	free(merges.objects);
+	object_array_clear(&merges);
 	return result->nr;
 }
 
@@ -1833,7 +1833,7 @@ int merge_submodule(struct object_id *result, const char *path,
 			print_commit((struct commit *) merges.objects[i].item);
 	}
 
-	free(merges.objects);
+	object_array_clear(&merges);
 	return 0;
 }