diff --git a/builtin/fsck.c b/builtin/fsck.c
index bacc899a32..3d9ee310d2 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -778,7 +778,7 @@ int cmd_fsck(int argc, const char **argv, const char *prefix)
 	 * default ones from .git/refs. We also consider the index file
 	 * in this case (ie this implies --cache).
 	 */
-	if (!heads) {
+	if (!argc) {
 		get_default_heads();
 		keep_cache_objects = 1;
 	}
diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh
index 6b6db62c4e..509d69c90e 100755
--- a/t/t1450-fsck.sh
+++ b/t/t1450-fsck.sh
@@ -616,4 +616,15 @@ test_expect_success 'fsck $name notices bogus $name' '
 	test_must_fail git fsck $_z40
 '
 
+test_expect_success 'bogus head does not fallback to all heads' '
+	# set up a case that will cause a reachability complaint
+	echo to-be-deleted >foo &&
+	git add foo &&
+	blob=$(git rev-parse :foo) &&
+	test_when_finished "git rm --cached foo" &&
+	remove_object $blob &&
+	test_must_fail git fsck $_z40 >out 2>&1 &&
+	! grep $blob out
+'
+
 test_done