[tz] proposed changes for Win32 and a improved mktime() algorithm

[Zefram]

Paul Eggert wrote:
>I think you need to look at other parts of the standard. C11 6.3.2.1
>paragraph 2

That does change things, thanks.  I concur with you that that paragraph
(on lvalue conversion) does make the idiom in question undefined
behaviour.  Interestingly, that sentence is new in C11; C99 doesn't
have it.  (I had been looking at C99.)  After a bit more looking around,
I think my earlier analysis still holds for C99.  This change between
versions is a bit surprising.

-zefram