[Mingw-cross-env-list] isl fails to build for target x86_64-pc-linux-gnu

[Anast Gramm]

Hello, I've downloaded the mxe environment as described by the tutorial,
and I've edited my `settings.mk` file to contain the following:

    MXE_TARGETS := x86_64-w64-mingw32.static 
    LOCAL_PKG_LIST := qt5 opencv hdf5 gcc cc exiv2 cmake
    .DEFAULT_GOAL  := local-pkg-list
    local-pkg-list: $(LOCAL_PKG_LIST)

I am trying to cross compile a cpp application with cmake
to run on windows.

After invoking `make` the command fails with the following
errors:

    Failed to build package isl for target x86_64-pc-linux-gnu!
    ------------------------------------------------------------
    checking gmp.h presence... yes
    checking for gmp.h... yes
    checking for main in -lgmp... yes
    configure: error: gmp library too old
    make[1]: *** [Makefile:806: build-only-isl_x86_64-pc-linux-gnu] Error 1
    make[1]: Leaving directory '/opt/mxe'
    real    0m3.881s
    user    0m3.107s
    sys     0m0.818s
    ------------------------------------------------------------
    [log]      /opt/mxe/log/isl_x86_64-pc-linux-gnu
    
    make: *** [Makefile:794: /opt/mxe/usr/x86_64-pc-linux-gnu/installed/isl] 
Error 1

Also I noticed that just before trying to build isl, there was
a successful build of gmp.

Why is it building for pc-linux-gnu while I specified mingw32?
What am I doing wrong and the compilation fails?

Thank you for your time.

--

Anastasis