Re: pl/perl extension fails on Windows

On Wed, Nov 29, 2017 at 08:14:41PM -0800, Noah Misch wrote:
> 1. If $Config{gccversion} is nonempty, add _USE_32BIT_TIME_T.  This will do
>    the wrong thing if MinGW changes its default to match modern MSVC.  It will
>    do the wrong thing for a Perl built with "gcc -D__MINGW_USE_VC2005_COMPAT".
> 
> 2. When configuring the build, determine whether to add _USE_32BIT_TIME_T by
>    running a test program built with and without that symbol.  Perhaps have
>    the test program store and retrieve a PL_modglobal value.  (PL_modglobal
>    maps to a PerlInterpreter field that follows the fields sensitive to
>    _USE_32BIT_TIME_T, and perlapi documents it since 5.8.0 or earlier.)  This
>    is more principled than (1), but it will be more code and may have weird
>    interactions with rare Perl build options.
> 
> I am inclined toward (2) if it takes no more than roughly a hundred lines of
> code, else (1).  Opinions?  I regret investing in 32-bit Windows.  If there's
> any OS where a 32-bit PostgreSQL server makes sense today, it's not Windows.

Here's an implementation of (2).  This is more intricate than I hoped.  One
could argue for (1), but I estimate (2) wins by a nose.  I successfully tested
http://strawberryperl.com/download/5.14.4.1/strawberry-perl-5.14.4.1-32bit.msi
(Perl 5.14.4; MinGW-built; must have -D_USE_32BIT_TIME_T) and
http://get.enterprisedb.com/languagepacks/edb-languagepack-10-3-windows.exe
(Perl 5.24.0; MSVC-built; must not have -D_USE_32BIT_TIME_T).  I also tried
http://strawberryperl.com/download/5.8.9/strawberry-perl-5.8.9.5.msi, which
experienced a StackHash_0a9e crash during PERL_SYS_INIT3(), with or without
-D_USE_32BIT_TIME_T.  I expect that breakage is orthogonal.  I didn't have
ready access to obsolete MSVC-built Perl, so it will be interesting to see how
the buildfarm likes this.