diff --git a/contrib/libreadline/rlconf.h b/contrib/libreadline/rlconf.h
index 8f07db155df1..e5594ce27e99 100644
--- a/contrib/libreadline/rlconf.h
+++ b/contrib/libreadline/rlconf.h
@@ -32,7 +32,7 @@
 
 /* If defined, readline shows opening parens and braces when closing
    paren or brace entered. */
-/* #define PAREN_MATCHING */
+#define PAREN_MATCHING
 
 /* This definition is needed by readline.c, rltty.c, and signals.c. */
 /* If on, then readline handles signals in a way that doesn't screw. */