My clock shows wrong time for GMT!
My local time is correct (Tehran, IRAN = GMT +3:30), but as it's clear from the above screenshot, GMT (Greenwich) is 1 hour behind according to Google!
The UTC and Pacific times are correct (checked with Google).
Note that "Time & Date" settings are set to "Automatically from the Internet".
Any ideas to fix this?
Use UTC instead of GMT
The time entry "Greenwich" under the calender is confusing.
One could obviously think of GMT - Greenwich Mean Time, which is used very often.
But it could also be just the plain current time at the location Greenwich. That would be BST - British Summer Time.
The entry UTC is less ambiguous - and comparing at that entry, "Greenwich" can only be Greenwich local time, as GMT and UTC are the same, roughly.
GMT is not available as time zone at all. UTC should be used instead. That makes sense because GMT does not have a precise definition, which UTC does have.