1 files changed, 6 insertions, 0 deletions
diff --git a/object.c b/object.c
index 4e3d5dd856..86a246f1c3 100644
--- a/object.c
+++ b/object.c
@@ -286,6 +286,9 @@ rb_obj_taint(obj)
     VALUE obj;
 {
     rb_secure(4);
+    if (OBJ_FROZEN(obj)) {
+	rb_error_frozen("object");
+    }
     OBJ_TAINT(obj);
     return obj;
 }
@@ -295,6 +298,9 @@ rb_obj_untaint(obj)
     VALUE obj;
 {
     rb_secure(3);
+    if (OBJ_FROZEN(obj)) {
+	rb_error_frozen("object");
+    }
     FL_UNSET(obj, FL_TAINT);
     return obj;
 }