[clang] [LifetimeSafety] Diagnose UAF for aligned and nothrow new expressions (PR #202286)

[Zeyi Xu via cfe-commits]

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@@ -53,6 +53,9 @@ T *begin(T (&array)[N]);
 
 using size_t = decltype(sizeof(0));
 using nullptr_t = decltype(nullptr);
+enum class align_val_t : size_t {};
+struct nothrow_t {};
+extern const nothrow_t nothrow;
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zeyi2 wrote:

There is no specific reason on this, I just copied it from https://cppreference.com/cpp/memory/new/nothrow

IMO this would better reflect how `nothrow_t` is implemented in real `std`.

https://github.com/llvm/llvm-project/pull/202286