[llvm-branch-commits] Add pointer field protection feature. (PR #133538)

[Mark de Wever via llvm-branch-commits]

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@@ -1215,6 +1215,29 @@ typedef __char32_t char32_t;
 #    define _LIBCPP_HAS_EXPLICIT_THIS_PARAMETER 0
 #  endif
 
+#  if __has_feature(pointer_field_protection)
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mordante wrote:

Since this feature is an ABI break, it will cause ODR violations to these structs. I think we should ABI tag this in `_LIBCPP_ODR_SIGNATURE`.

https://github.com/llvm/llvm-project/pull/133538