diff --git a/builtin/commit.c b/builtin/commit.c
index 883c162..2ef44f1 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -858,7 +858,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	}
 
 	s->fp = fopen_for_writing(git_path_commit_editmsg());
-	if (s->fp == NULL)
+	if (!s->fp)
 		die_errno(_("could not open '%s'"), git_path_commit_editmsg());
 
 	/* Ignore status.displayCommentPrefix: we do need comments in COMMIT_EDITMSG. */