diff --git a/configure b/configure
index 8bccec5a71..b595496d3a 100755
--- a/configure
+++ b/configure
@@ -355,11 +355,15 @@ disable_weak(){
 }
 
 enable_safe(){
-    enable $(echo "$*" | sed 's/[^A-Za-z0-9_ ]/_/g')
+    for var; do
+        enable $(echo "$var" | sed 's/[^A-Za-z0-9_]/_/g')
+    done
 }
 
 disable_safe(){
-    disable $(echo "$*" | sed 's/[^A-Za-z0-9_ ]/_/g')
+    for var; do
+        disable $(echo "$var" | sed 's/[^A-Za-z0-9_]/_/g')
+    done
 }
 
 do_enable_deep(){