diff --git a/commit.c b/commit.c
index 521e49c309..ebc0eeab8f 100644
--- a/commit.c
+++ b/commit.c
@@ -581,7 +581,7 @@ static int compare_commits_by_author_date(const void *a_, const void *b_,
 	return 0;
 }
 
-static int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
+int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
 {
 	const struct commit *a = a_, *b = b_;
 	/* newer commits with larger date first */
diff --git a/commit.h b/commit.h
index 4d452dc96d..18a523495e 100644
--- a/commit.h
+++ b/commit.h
@@ -254,4 +254,6 @@ extern void print_commit_list(struct commit_list *list,
  */
 extern void check_commit_signature(const struct commit* commit, struct signature_check *sigc);
 
+int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused);
+
 #endif /* COMMIT_H */