diff --git a/server/gc/verify.c b/server/gc/verify.c
index 67bf9219..bba0bb87 100644
--- a/server/gc/verify.c
+++ b/server/gc/verify.c
@@ -29,6 +29,7 @@ check_blocks (VerifyData *data, const char *file_id)
     for (i = 0; i < seafile->n_blocks; ++i) {
         if (!g_hash_table_lookup(data->exist_blocks, seafile->blk_sha1s[i])) {
             seaf_message ("Block %s is missing.\n", seafile->blk_sha1s[i]);
+            return -1;
         }
     }