diff --git a/commit.h b/commit.h
index 6d857f06c1..1283d2a51f 100644
--- a/commit.h
+++ b/commit.h
@@ -313,11 +313,6 @@ extern int interactive_add(int argc, const char **argv, const char *prefix, int
 extern int run_add_interactive(const char *revision, const char *patch_mode,
 			       const struct pathspec *pathspec);
 
-static inline int single_parent(struct commit *commit)
-{
-	return commit->parents && !commit->parents->next;
-}
-
 struct commit_list *reduce_heads(struct commit_list *heads);
 
 struct commit_extra_header {