check_cxx_source_compiles(
  "
  #define WIN32_LEAN_AND_MEAN
  #include <winsock2.h>
  #include <windows.h>
  #include <afunix.h>
  int main(){(void)sizeof(((struct sockaddr_un *)0)->sun_path); return 0;}
  "
  HAVE_AF_UNIX_H)