Re: [RFC] Correctly handling MinGW-w64

[Paul Eggert]

Óscar Fuentes wrote:
> +dnl We need to distinguish MinGW32 toolset from its spin-off
> +dnl MinGW-w64. (This has nothing to do with word size.)
> +MINGW_W64=no
> +if test $opsys = mingw32; then
> +    AC_CHECK_DECL(__MINGW64_VERSION_MAJOR,
> +                   MINGW_W64=yes,
> +                   MINGW_W64=no,
> +                   [#include <_mingw.h>])
> +    if test "$MINGW_W64" = "yes"; then
> +       AC_DEFINE([MINGW_W64], 1,
> +          [Define to 1 if you are using the MinGW-w64 toolset, regardless of 
> word size.])
> +    fi
> +fi

Why does the above need to be in configure.ac?  Can the relevant code just 
inspect __MINGW64_VERSION_MAJOR instead of inspecting MINGW_W64?  Or, if we 
prefer to use our own symbol, can we just put something like this:

#ifdef __MINGW64_VERSION_MAJOR
# define MINGW_W64 1
#endif

into ms-w32.h or into some other header specific to Microsoft Windows?