Re: MinGW build on master fails with Error 127

[Eli Zaretskii <eliz@gnu.org>]

> From: Óscar Fuentes <ofv@wanadoo.es>
> Cc: emacs-devel@gnu.org
> Date: Sat, 24 Dec 2022 19:56:51 +0100
> 
> > Does the wording in nt/INSTALL.W64 guide users to only one of these
> > two variants (and if so, to which one), or is it generic, and the user
> > will have to choose when they install MinGW?
> 
> It definitively points to the MINGW64 variant (the traditional one that
> uses MSVCRT *and* runs on x86_64) because it lists the packages with the
> mingw-w64-x86_64- prefix.

OK, that's good.

> A cursory look also shows some important problems with that document.
> For instance, gives a link to download the MSYS2 installer instead of
> directing the user to the MSYS2 project webpage (msys2.org). That link
> is no longer valid.

Fixes for stale and outdated URLs will be appreciated.

> In general, I don't know why we (Emacs) make the effort of providing so
> much guidance for building under MSYS2 when no similar level of detail
> is provided for Debian, Fedora, Cygwin, etc.

The Windows users typically need to do more to arrange for a working
build environment than users on Posix hosts.

> Actually, building Emacs under MSYS2 is almost the same as the other
> platforms.

Once you have a suitable build environment, yes.  But until you get
there, no.

> >> The commit message says "fclose fail during atexit as if they were
> >> already closed" but indeed it doesn't describe a user-visible problem. I
> >> can ask for more details, if you are interested.
> >
> > I am.
> 
> Ok, I'll ask the patch author.

My guess is that close_stream (which is a Gnulib module) does
something that fails with UCRT.  For example, it uses __fpending, and
AFAIR that's defined in Emacs for Windows using the MSVCRT internals
of the FILE object, so maybe it needs to be amended.

In general, I would suggest to step into close_stream and see what
exactly fails there.