[clang] Initial implementation of P2719 (PR #113510)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,73 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++2c -fcxx-type-aware-allocators -fexceptions 
+
+namespace std {
+  template <class T> struct type_identity {};
+  enum class align_val_t : __SIZE_TYPE__ {};
+  struct destroying_delete_t { explicit destroying_delete_t() = default; };
+}
+
+using size_t = __SIZE_TYPE__;
+
+struct S1 {
+  constexpr explicit S1() : i(5) {  }
+  const int i;
+};
+
+void *operator new(std::type_identity<S1>, size_t sz);
+// expected-note at -1 {{candidate function not viable: no known conversion from 'type_identity<S2>' to 'type_identity<S1>' for 1st argument}}
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erichkeane wrote:

Same issue as before with the 'note'.

https://github.com/llvm/llvm-project/pull/113510