trouble with building MinGW-w64 windows-hosted toolchain using Linux

[Jim Wilson]

On Thu, May 14, 2020 at 5:26 AM <i.nixman@autistici.org> wrote:
>            if (ecx & bit_AVX512VNNI)
>                      ^~~~~~~~~~~~~~
>                      bit_AVX512VBMI

These bit_* macros are in cpuid.h.  Maybe you have more than one copy
of this file, and are accidentally using an older version than the one
in the gcc source tree?  I see that you have lots of -I and -isystem
options which normally should not be needed.  The gcc one is
gcc/config/i386/cpuid.h and should get installed into the gcc install
tree.

In general, you can find some useful info about cross building
toolchains in the crosstool-ng project.
https://crosstool-ng.github.io/

Note that gmp, mpfr, mpc, and isil can just be dropped into the gcc
source tree, alongside the other libraries like libgcc and libstdc++,
and the gcc Makefile will build them for you as part of the gcc build.
That should also work for zlib but I haven't tried that in a while.
For libiconv, it is simpler to just use --disable-nls, but it looks
like the toplevel makefile has support for that too, so adding that
into the gcc source tree looks like it would work too.

Jim