--- configure	2018-12-22 22:58:42 UTC
+++ configure	
@@ -8780,7 +8780,10 @@ case $host_os in
 	cf_xopen_source="-D_DARWIN_C_SOURCE"
 	cf_XOPEN_SOURCE=
 	;;
-(freebsd*|dragonfly*|midnightbsd*)
+(freebsd*)
+	cf_XOPEN_SOURCE=
+	;;
+(dragonfly*|midnightbsd*)
 	# 5.x headers associate
 	#	_XOPEN_SOURCE=600 with _POSIX_C_SOURCE=200112L
 	#	_XOPEN_SOURCE=500 with _POSIX_C_SOURCE=199506L