diff --git a/cache.h b/cache.h
index 3e6a914db..de290c4f0 100644
--- a/cache.h
+++ b/cache.h
@@ -1143,7 +1143,7 @@ extern void prepare_alt_odb(void);
 extern void read_info_alternates(const char * relative_base, int depth);
 extern void add_to_alternates_file(const char *reference);
 typedef int alt_odb_fn(struct alternate_object_database *, void *);
-extern void foreach_alt_odb(alt_odb_fn, void*);
+extern int foreach_alt_odb(alt_odb_fn, void*);
 
 struct pack_window {
 	struct pack_window *next;
diff --git a/sha1_file.c b/sha1_file.c
index 6f18c22ab..aaa3c5286 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -412,14 +412,18 @@ void add_to_alternates_file(const char *reference)
 		link_alt_odb_entries(alt, strlen(alt), '\n', NULL, 0);
 }
 
-void foreach_alt_odb(alt_odb_fn fn, void *cb)
+int foreach_alt_odb(alt_odb_fn fn, void *cb)
 {
 	struct alternate_object_database *ent;
+	int r = 0;
 
 	prepare_alt_odb();
-	for (ent = alt_odb_list; ent; ent = ent->next)
-		if (fn(ent, cb))
-			return;
+	for (ent = alt_odb_list; ent; ent = ent->next) {
+		r = fn(ent, cb);
+		if (r)
+			break;
+	}
+	return r;
 }
 
 void prepare_alt_odb(void)