[m-rev.] for review: more fixes for building on Windows

[Peter Wang]

On Thu, 23 Jan 2020 14:51:47 +1100 (AEDT), Julien Fischer <jfischer at opturion.com> wrote:
> 
> More fixes for building on Windows.
> 
> The configuration types returned by autoconf for MinGW have a long and
> complicated history. For the current version of config.sub we use they will
> match one of:
> 
>      *-pc-msys      (i.e. executables linked against the MSYS DLLs)
>      *-pc-mingw32   (i.e. 32-bit native executables)
>      *-pc-mingw64   (i.e. 64-bit native executables)
> 
> We do not support the first possibility, but do support the other two.
> 
> Older versions of config.sub reported MinGW64 as *-w64-mingw{32,64} and pieces
> of the existing configure script still assume that. This diff changes the
> configure script to match what is currently returned by config.sub.

Did something change? I thought the "w64" bit signified the
MinGW-w64 port, which is a separate project from MinGW?

I install mingw-w64 package on Ubuntu (probably the same on Debian)
which provides the binaries /usr/bin/x86_64-w64-mingw32-gcc etc.
Then I run configure mercury with

    ./tools/configure_mingw_cross --host=x86_64-w64-mingw32

which says:

checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-w64-mingw32


Peter