[PATCH] Fix build issues with mingw toolchain

[Tom Tromey]

>>>>> "Bernd" == Bernd Edlinger <bernd.edlinger@hotmail.de> writes:

>> I wonder if we could change _WIN32_WINNT when threading is enabled, so
>> the new gcc support could be used.

Bernd> frankly I don't understand at all why the _WIN32_WINNT is set to this
Bernd> specific value, and maybe that was a good idea when windows XP was the
Bernd> latest version.  My feeling would be to remove that define all together.

The addition itself seems to be commit 353ea2d1, which has some
explanation.  I gather the idea is that, this way, a gdb built on
Windows will work all the way back to NT.

I tried changing the value but Eli objected:

https://sourceware.org/pipermail/gdb-patches/2021-October/182443.html

Internally at AdaCore we still have this part of the change installed,
precisely to pick up the mingw threading support from gcc; plus we have
no need for Windows XP.

>From https://en.wikipedia.org/wiki/Windows_XP#Support_lifecycle, I
gather that XP is still in reasonably wide use.  I'm not sure how many
developers use it, though, or even if gdb actually does run there, not
having access to such a machine myself.

I'm sympathetic to changing this somehow but I don't know how to make
progress on it.

Tom