[META] Portability issues to MinGW.org compilers

[p5pRT]

Migrated from rt.perl.org#128644 (status was 'new')

Searchable as RT128644$

[toddr]

#15446
#15450
#15451
#15453
#15455

[toddr]

This would probably be better tracked at https://github.com/Perl/perl5/labels/MinGW.org%20Portability

[dur-randir]

Do we still support http://mingw.org/ toolchain? Last time i've tried only http://mingw-w64.org/ works.

[toddr]

This is a good question. My conclusion after looking at all distro-mswin32 tickets in the past 2 days is that we need to decide what we support and close the rest.