diff --git a/gcc/config.gcc b/gcc/config.gcc
index 15318b20ce0..3e8bd76ae13 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -4083,9 +4083,8 @@ fi
 supported_defaults=
 case "${target}" in
 	aarch64*-*-*)
-		supported_defaults="abi cpu arch"
-		for which in cpu arch; do
-
+		supported_defaults="abi cpu arch tune"
+		for which in cpu arch tune; do
 			eval "val=\$with_$which"
 			base_val=`echo $val | sed -e 's/\+.*//'`
 			ext_val=`echo $val | sed -e 's/[a-z0-9.-]\+//'`