https://bugs.winehq.org/show_bug.cgi?id=18787
--- Comment #12 from Austin English austinenglish@gmail.com --- Presumably still present in wine-3.13. interlocked.c now uses gcc defines by default on i386, but given that windef.h doesn't have a __SUNPRO_C check, I can't imagine this works.
I'd suggest filing a bug with illumos, since they're the best positioned (and most likely interested) in fixing this. If someone does, please link that bug here.