Hi,
I tried building wine 6.8 with mingw. All fine, just one problem, it reports error "undefined reference to `sincos'". Why, you may ask, since wine never calls sincos function? Well, it seems to be because mingw gcc 11 enables sincos optimization: [0]. But, wine uses -nodefaultlibs, intending to provide libc functions with msvcrt; however, wine msvcrt doesn't implement any sincos. So, there is a mismatch: gcc accepts mingw claim to implement sincos (ok since mingwex implements it), then generates call to sincos, then fails at link time (because msvcrt does not implement it).
After adding -fno-builtin-{sin,cos}{,f} to CFLAGS, wine compiled and ran OK.
This issue seems to be worked around for winelib builds by adding -fno-builtin, so that gcc will not generate sincos (or most other problematic functions).
I think this issue could be worked around by adding those -fno-builtin-* flags for mingw builds. However, I think the sin/cos->sincos optimization is a good one, so maybe we could instead add sincos forwarder in msvcrt (calling sin+cos separately in case sincos is not implemented in libc?).
CCed mingw-w64-public@lists.sourceforge.net due to potential relevance and felixonmars@archlinux.org due to maintaining wine and mingw-gcc on Arch. You may need to subscribe in order to reply all. I look forward to hearing your thoughts.
Regards, Alex.
[0] https://github.com/gcc-mirror/gcc/commit/4f48f31bbfc10697296ff004a92614d9249...