Always explicitly set tm_isdst before calling mktime().

Except in rare cases, we want to set it to -1 so that we let mktime()
determine whether DST/Summer Time was in effect at the given date and
time rather than pretending that we know whether it's in effect or not.

Change-Id: I0ea75317dd308a515cedf4d1260b583e1592cc9b
Reviewed-on: https://code.wireshark.org/review/27431
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 1 insertions, 0 deletions

diff --git a/ui/time_shift.c b/ui/time_shift.c
index 74d359f7cf..edd460a5d1 100644
--- a/ui/time_shift.c
+++ b/ui/time_shift.c
@@ -244,6 +244,7 @@ time_string_to_nstime(const gchar *time_text, nstime_t *packettime, nstime_t *ns
     tm.tm_hour = h;
     tm.tm_min = m;
     tm.tm_sec = (int)floorl(f);
+    tm.tm_isdst = -1;
     tt = mktime(&tm);
     if (tt == -1) {
         return "Mktime went wrong. Is the time valid?";