diff --git a/src/time/__tz.c b/src/time/__tz.c
index fbe3d492..93d59e8d 100644
--- a/src/time/__tz.c
+++ b/src/time/__tz.c
@@ -166,6 +166,7 @@ static void do_tzset()
 				}
 			}
 		}
+		if (!map) s = __gmt;
 	}
 
 	zi = map;