[libcxx-commits] [libcxx] [libc++] Make std::pair trivially copyable if its members are (PR #89652)

[Louis Dionne via libcxx-commits]

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@@ -98,6 +98,8 @@
 // and WCHAR_MAX. This ABI setting determines whether we should instead track whether the fill
 // value has been initialized using a separate boolean, which changes the ABI.
 #  define _LIBCPP_ABI_IOS_ALLOW_ARBITRARY_FILL_VALUE
+// Make a std::pair of trivially copyable types trivially copyable
----------------
ldionne wrote:

```suggestion
// Make a std::pair of trivially copyable types trivially copyable.
// While this technically doesn't change the layout of pair itself, other types may
// decide to programmatically change their representation based on whether
// something is trivially copyable, which is why we consider this potentially ABI-breaking.
```

https://github.com/llvm/llvm-project/pull/89652