From 0ee8e59d0ac281402395185c8c40d3dc5fdb93d6 Mon Sep 17 00:00:00 2001
From: Piotr Podusowski <podusowski@gmail.com>
Date: Fri, 16 Mar 2018 11:47:23 +0100
Subject: [PATCH] use char type directly to avoid invalid aliasing

---
 include/boost/function/function_template.hpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/boost/function/function_template.hpp b/include/boost/function/function_template.hpp
index 0b05940..c6bbd2d 100644
--- a/include/boost/function/function_template.hpp
+++ b/include/boost/function/function_template.hpp
@@ -992,7 +992,9 @@ namespace boost {
         if (!f.empty()) {
           this->vtable = f.vtable;
           if (this->has_trivial_copy_and_destroy())
-            this->functor = f.functor;
+            // Don't operate on storage directly since union type doesn't relax
+            // strict aliasing rules, despite of having member char type.
+            std::memcpy(this->functor.data, f.functor.data, sizeof(this->functor.data));
           else
             get_vtable()->base.manager(f.functor, this->functor,
                                      boost::detail::function::move_functor_tag);