[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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@@ -1386,55 +1716,21 @@ _LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::resize(size_type __n
     if (__new_size <= capacity())
       __construct_at_end(__new_size - __current_size, __x);
     else {
-      __split_buffer<value_type, allocator_type&> __v(__recommend(__new_size), __current_size, __alloc_);
+      __split_buffer __v(__recommend(__new_size), __current_size, __allocator_ref());
       __v.__construct_at_end(__new_size - __current_size, __x);
       __swap_out_circular_buffer(__v);
     }
   } else if (__current_size > __new_size) {
-    this->__destruct_at_end(this->__begin_ + __new_size);
+    this->__destruct_at_end(__raw_begin() + __new_size);
   }
 }
 
-template <class _Tp, class _Allocator>
-_LIBCPP_CONSTEXPR_SINCE_CXX20 void vector<_Tp, _Allocator>::swap(vector& __x)
-#if _LIBCPP_STD_VER >= 14
-    _NOEXCEPT
-#else
-    _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<allocator_type>)
-#endif
-{
-  _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
-      __alloc_traits::propagate_on_container_swap::value || this->__alloc_ == __x.__alloc_,
-      "vector::swap: Either propagate_on_container_swap must be true"
-      " or the allocators must compare equal");
-  std::swap(this->__begin_, __x.__begin_);
-  std::swap(this->__end_, __x.__end_);
-  std::swap(this->__cap_, __x.__cap_);
-  std::__swap_allocator(this->__alloc_, __x.__alloc_);
-}
-
-template <class _Tp, class _Allocator>
-_LIBCPP_CONSTEXPR_SINCE_CXX20 bool vector<_Tp, _Allocator>::__invariants() const {
-  if (this->__begin_ == nullptr) {
-    if (this->__end_ != nullptr || this->__cap_ != nullptr)
-      return false;
-  } else {
-    if (this->__begin_ > this->__end_)
-      return false;
-    if (this->__begin_ == this->__cap_)
-      return false;
-    if (this->__end_ > this->__cap_)
-      return false;
-  }
-  return true;
-}
-
 #if _LIBCPP_STD_VER >= 20
-template <>
-inline constexpr bool __format::__enable_insertable<vector<char>> = true;
+template <class _Allocator>
+inline constexpr bool __format::__enable_insertable<vector<char, _Allocator>> = true;
----------------
cjdb wrote:

Removed.

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