https://bugs.winehq.org/show_bug.cgi?id=50761
--- Comment #1 from Erich E. Hoover erich.e.hoover@gmail.com --- I'm really sorry Gijs, it appears that I missed whatever headers are necessary on MacOS to pull that in when I moved this code. Would you please try adding these headers (from the fstatfs mac man page)?: #ifdef HAVE_SYS_PARAM_H #include <sys/param.h> #endif #ifdef HAVE_SYS_MOUNT_H #include <sys/mount.h> #endif