DXVK 1.6 does not seem to build with Winelib anymore and upstream has
deprecated Winelib for a while.

I'm trying to compile dxvk with mingw instead.

How do I use mingw to build a package (dxvk uses meson)?

Can I use the #:system argument?  Otherwise I could add mingw as input
like this:

--8<---------------cut here---------------start------------->8---
(make-mingw-w64 "x86_64"
 #:xgcc (cross-gcc "x86_64-linux-gnu")
 #:xbinutils (cross-binutils "x86_64-linux-gnu")
 #:with-winpthreads? #t)
--8<---------------cut here---------------end--------------->8---

or, for the 32-bit build (dxvk needs both)

--8<---------------cut here---------------start------------->8---
(make-mingw-w64 "i686"
 #:xgcc (cross-gcc "i686-linux-gnu")
 #:xbinutils (cross-binutils "i686-linux-gnu")
 #:with-winpthreads? #t)
--8<---------------cut here---------------end--------------->8---

I can't seem to be able to build the mingw compiler though.
The following fails on master

--8<---------------cut here---------------start------------->8---
./guix/pre-inst-env guix build -e '((@@ (gnu packages mingw) make-mingw-w64) "i686" #:xgcc ((@@ (gnu packages cross-base) cross-gcc) "i686-linux-gnu") #:xbinutils ((@@ (gnu packages cross-base) cross-binutils) "i686-linux-gnu") #:with-winpthreads? #t)'
--8<---------------cut here---------------end--------------->8---

with

--8<---------------cut here---------------start------------->8---
checking how to run the C preprocessor... /gnu/store/0qqmpdm7v8jigvvv5i05ihdz2jlbmjmf-gcc-cross-sans-libc-i686-linux-gnu-7.5.0/bin/i686-w64-mingw32-cpp
configure: error: in `/tmp/guix-build-mingw-w64-i686-7.0.0.drv-0/mingw-w64-v7.0.0/mingw-w64-crt':
configure: error: C preprocessor "/gnu/store/0qqmpdm7v8jigvvv5i05ihdz2jlbmjmf-gcc-cross-sans-libc-i686-linux-gnu-7.5.0/bin/i686-w64-mingw32-cpp" fails sanity check
See `config.log' for more details
configure: error: ./configure failed for mingw-w64-crt
command "/gnu/store/pwcp239kjf7lnj5i4lkdzcfcxwcfyk72-bash-minimal-5.0.16/bin/bash" "./configure" "CONFIG_SHELL=/gnu/store/pwcp239kjf7lnj5i4lkdzcfcxwcfyk72-bash-minimal-5.0.16/bin/bash" "SHELL=/gnu/store/pwcp239kjf7lnj5i4lkdzcfcxwcfyk72-bash-minimal-5.0.16/bin/bash" "--prefix=/gnu/store/x7pl1lh5x81s047bgp3j00dp2qrqkviv-mingw-w64-i686-7.0.0" "--enable-fast-install" "--build=x86_64-unknown-linux-gnu" "--host=i686-w64-mingw32" failed with status 1
builder for `/gnu/store/i5i6zq8b6knrr96l554d8lw2pd2mbii6-mingw-w64-i686-7.0.0.drv' failed with exit code 1
--8<---------------cut here---------------end--------------->8---

Any idea?

-- 
Pierre Neidhardt
https://ambrevar.xyz/