[clang] [SemaCXX] Make __builtin_addressof more like std::addressof (PR #78035)

[Shafik Yaghmour via cfe-commits]

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@@ -39,7 +39,43 @@ namespace addressof {
   struct U { int n : 5; } u;
   int *pbf = __builtin_addressof(u.n); // expected-error {{address of bit-field requested}}
 
-  S *ptmp = __builtin_addressof(S{}); // expected-error {{taking the address of a temporary}} expected-warning {{temporary whose address is used as value of local variable 'ptmp' will be destroyed at the end of the full-expression}}
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shafik wrote:

Do we understand why we lost the `warning` diagnostic?

https://github.com/llvm/llvm-project/pull/78035