[libcxx-commits] [libcxx] [libcxx] adds a size-based representation for `vector`'s unstable ABI (PR #155330)

[Christopher Di Bella via libcxx-commits]

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@@ -188,6 +189,57 @@ public:
     __back_cap_  = __other.__back_cap_;
   }
 
+  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
+  __swap_layouts(pointer& __begin, pointer& __end, pointer& __back_capacity) {
+    std::swap(__begin_, __begin);
+    std::swap(__end_, __end);
+    std::swap(__back_cap_, __back_capacity);
+  }
+
+  /// `__relocate` relocates the objects in `[__begin_, __size())` into the front of `__buffer` and
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cjdb wrote:

I cut/pasted [this comment](https://github.com/llvm/llvm-project/blob/main/libcxx/include/__vector/vector.h#L857-L859), but forgot to edit it for its new home. Should hopefully read sensibly now.

https://github.com/llvm/llvm-project/pull/155330