--- a/configure.ac
+++ b/configure.ac
@@ -277,7 +277,7 @@ case "$THREADS" in
         ;;
     esac
     ;;
- win32)
+ win32 | mcf)
     AC_DEFINE(GC_THREADS)
     use_parallel_mark=$enable_parallel_mark
     if test "${enable_parallel_mark}" != no \