fix mishandling of empty or blank TZ environment variable

the empty TZ string was matching equal to the initial value of the
cached TZ name, thus causing do_tzset never to run and never to
initialize the time zone data.

diff --git a/src/time/__tz.c b/src/time/__tz.c
index a76a7b4865149305d693aababac85a6c64ec1df1..36b59802aa5865cbbf00972cad8e4bcb2070aa18 100644 (file)
--- a/src/time/__tz.c
+++ b/src/time/__tz.c
@@ -127,7 +127,7 @@ static void do_tzset()
                "/usr/share/zoneinfo/\0/share/zoneinfo/\0/etc/zoneinfo/\0";
 
        s = getenv("TZ");
-       if (!s) s = "";
+       if (!s || !*s) s = "GMT0";
 
        if (old_tz && !strcmp(s, old_tz)) return;