[llvm-branch-commits] [libcxx] Prepare libcxx and libcxxabi for pointer field protection. (PR #151651)

[Louis Dionne via llvm-branch-commits]

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@@ -34,10 +34,13 @@ template <class _Tp, class = void>
 struct __libcpp_is_trivially_relocatable : is_trivially_copyable<_Tp> {};
 #endif
 
+// __trivially_relocatable on libc++'s builtin types does not currently return the right answer with PFP.
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ldionne wrote:

Coming back to this, wouldn't it be sufficient to say that when PFP is enabled, `__libcpp_is_trivially_relocatable<_Tp*>` is false via a partial specialization?

I think a few types like `locale` would then have to be adjusted to be conditional on whether e.g. `__imp*` is TR, but I think that should be relatively small. Most other classes which are templates should already handle this correctly by determining their TR-ness conditionally on their members. WDYT?

https://github.com/llvm/llvm-project/pull/151651