1 files changed, 1 insertions, 1 deletions
diff --git a/object.c b/object.c
index be551bd82a..b515b45202 100644
--- a/object.c
+++ b/object.c
@@ -386,7 +386,7 @@ static VALUE
 mod_to_s(class)
     VALUE class;
 {
-    return rb_class_path(class);
+    return str_dup(rb_class_path(class));
 }
 
 static VALUE