1 files changed, 2 insertions, 2 deletions
diff --git a/proc.c b/proc.c
index 3dcbf60d31..5b1313a468 100644
--- a/proc.c
+++ b/proc.c
@@ -1169,8 +1169,8 @@ rb_method_name_error(VALUE klass, VALUE str)
     else if (RB_TYPE_P(c, T_MODULE)) {
 	s0 = " module";
     }
-    rb_name_error_str(str, "undefined method `%s' for%s `%s'",
-		      RSTRING_PTR(str), s0, rb_class2name(c));
+    rb_name_error_str(str, "undefined method `%"PRIsVALUE"' for%s `%"PRIsVALUE"'",
+		      QUOTE(str), s0, rb_class_name(c));
 }
 
 /*