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

[A. Jiang via libcxx-commits]

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@@ -282,7 +293,18 @@ template <class _ValueType,
 #  endif
           >
 class __deque_iterator {
-  typedef _MapPointer __map_iterator;
+  using __map_iterator _LIBCPP_NODEBUG = __get_deque_map_iterator<_ValueType, _MapPointer>;
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frederick-vs-ja wrote:

It isn't. As noted in the comments, what we want is `FancyPtr<const FancyPtr<_ValueType>>` here (if the iterator is const), but not `FancyPtr<_ValueType>`.

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