--- configure.orig	2014-06-03 20:08:54 UTC
+++ configure
@@ -15639,6 +15639,9 @@ else
 fi
 
 case "${host}" in
+  *-bsdsunix*|*-freebsd*)
+    gc_use_mmap=yes
+    ;;
   *-linux*)
     # FIXME: This seems to be no longer needed as configured in gcconfig.h
     #gc_use_mmap=yes