[libcxx-commits] [libcxx] [libc++] Fix strict aliasing violation for `deque::const_iterator` (PR #136067)

[Nikolas Klauser via libcxx-commits]

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@@ -725,24 +737,24 @@ public:
   // iterators:
 
   [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT {
-    __map_pointer __mp = __map_.begin() + __start_ / __block_size;
+    auto __mp = static_cast<const __map&>(__map_).begin() + __start_ / __block_size;
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philnik777 wrote:

Why does this need to be cast to `const __map&`? Same below.

https://github.com/llvm/llvm-project/pull/136067