dxvk: winelib build fails with meson 0.50

With meson 0.50, winelib check fails. Corresponding meson-log.txt part:

Native C++ compiler: c++ (gcc 8.3.1 "c++ (GCC) 8.3.1 20190223 (Red Hat 8.3.1-2)")
Cross C++ compiler: wineg++ (gcc 8.3.1)
Build machine cpu family: x86_64
Build machine cpu: x86_64
Running compile:
Working directory:  /tmp/tmphnxfqgtd
Command line:  c++ /tmp/tmphnxfqgtd/testfile.cpp -pipe -D_FILE_OFFSET_BITS=64 -c -o /tmp/tmphnxfqgtd/output.obj -m64 --no-gnu-unique -O0 -fpermissive 

Code:
 #ifndef __WINE__
#error 1
#endif
Compiler stdout:
 
Compiler stderr:
 /tmp/tmphnxfqgtd/testfile.cpp:2:2: error: #error 1
 #error 1
  ^~~~~

Checking if "winelib check" compiles: NO

With meson 0.48 dxvk builds fine. I guess the problem is that meson uses native compiler instead of cross-compiler to run the compiler test (dxvk_compiler.compiles(code, name: 'winelib check')).