Here is the meson log:

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Build started at 2019-03-28T15:20:27.700496
Main binary: /gnu/store/r68bi4640vm0s7zsgyk7shsag8ibl3nc-python-wrapper-3.7.0/bin/python
Python system: Linux
The Meson build system
Version: 0.49.0
Source dir: /tmp/guix-build-dxvk-1.0.1.drv-0/source
Build dir: /tmp/guix-build-dxvk-1.0.1.drv-0/build
Build type: native build
Project name: dxvk
Project version: v1.0.1
Sanity testing C compiler: gcc
Is cross compiler: False.
Sanity check compiler command line: gcc /tmp/guix-build-dxvk-1.0.1.drv-0/build/meson-private/sanitycheckc.c -o /tmp/guix-build-dxvk-1.0.1.drv-0/build/meson-private/sanitycheckc.exe
Sanity check compile stdout:

-----
Sanity check compile stderr:
/gnu/store/d8gir0hpm64krsq63rbrzzkgrisvic1a-mingw-w64-5.0.4/lib/crt1.o: file not recognized: file format not recognized
collect2: error: ld returned 1 exit status

-----

meson.build:1:0: ERROR:  Compiler gcc can not compile programs.
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Note that

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winegcc /tmp/guix-build-dxvk-1.0.1.drv-0/build/meson-private/sanitycheckc.c -o /tmp/guix-build-dxvk-1.0.1.drv-0/build/meson-private/sanitycheckc.exe
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works.

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