Subject: Re: bug#22302: 25.1.50; time-stamp ignores time-stamp-time-zone

From: Paul Eggert <[email-masked]>
Date: Tue, 12 Jan 2016 13:29:23 -0800

On 01/12/2016 12:51 PM, Eli Zaretskii wrote:
>>   don't know what MS-Windows does with TZ="UTC"
> Nothing.  It doesn't understand that.  The MS-Windows time routines
> need an explicit offset from UTC to be able to account for the
> timezone.  So unless you say UTC-0, nothing will happen.

In that case I'm a bit puzzled. Before today, lines like this:

# time-stamp-time-zone: "UTC"

appeared in files like build-aux/gitlog-to-changelog. Emacs implements 
these lines by temporarily setting the TZ environment variable to "UTC". 
If that setting is ineffective on MS-Windows, presumably any relevant 
time stamps were generated in local time instead, which is not wanted.

Perhaps no MS-Windows users noticed, or none of them bothered to file a 
bug report.

Or perhaps "nothing will happen" means "no offset from UTC will be 
applied", which means that unrecognized TZ settings act like UTC; this 
is what tzcode does.

Or it could be something else, though I don't know what.