From 8f81d9ad909c91dcc5f194b7befc483ab65a8a9a Mon Sep 17 00:00:00 2001
From: Gunnar Beutner <gbeutner@serenityos.org>
Date: Fri, 4 Jun 2021 10:51:13 +0200
Subject: [PATCH] AK: Verify that functions aren't modified while they're being
 invoked

A Function object should not be set to a different functor while the
original functor is currently executing.
---
 AK/Function.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/AK/Function.h b/AK/Function.h
index 85ee9de9b1..06e3f3a75d 100644
--- a/AK/Function.h
+++ b/AK/Function.h
@@ -205,6 +205,7 @@ private:
     template<typename Callable>
     void init_with_callable(Callable&& callable)
     {
+        VERIFY(m_call_nesting_level == 0);
         using WrapperType = CallableWrapper<Callable>;
         if constexpr (sizeof(WrapperType) > inline_capacity) {
             *bit_cast<CallableWrapperBase**>(&m_storage) = new WrapperType(move(callable));