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

[Erich Keane via cfe-commits]

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@@ -2234,6 +2234,17 @@ enum class CXXNewInitializationStyle {
   Braces
 };
 
+struct ImplicitAllocationParameters {
+  bool PassTypeIdentity;
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erichkeane wrote:

minor preference for all of these being bitfields, or perhaps make this an `enum` type that we can use as flags (and unify both?).

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