* fix warning

src/database.c

@@ -383,7 +383,7 @@ simdb_search_free(simdb_search_t *search) {
  */
 static int
 simdb_search(simdb_t *db, simdb_search_t *search, simdb_urec_t *sample, int skip) {
-  simdb_match_t *matches;
+  simdb_match_t *matches = NULL;
   simdb_match_t match;
   simdb_urec_t *rec, *data = NULL;
   const int blksize = 4096;