diff --git a/src/interpreter/vtable.rs b/src/interpreter/vtable.rs
index 154a9ee8c5a6..d4b347af0671 100644
--- a/src/interpreter/vtable.rs
+++ b/src/interpreter/vtable.rs
@@ -96,6 +96,8 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
             }
         }
 
+        self.memory.freeze(vtable.alloc_id)?;
+
         Ok(vtable)
     }