Probably affects Linux as well with non-standard libc that doesn't bootleg <stdarg.h>.
In file included from C:/Projects/glslang/glslang/MachineIndependent/glslang.y:59:0:
glslang/MachineIndependent/ParseHelper.h:276:24: error: 'va_list' has not been declared
va_list args);
^~~~~~~
Probably affects Linux as well with non-standard libc that doesn't bootleg
<stdarg.h>
.