[clang] [clang] Add tests for some CWG 5xx issues (PR #87909)

[Vlad Serebrennikov via cfe-commits]

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@@ -661,6 +680,10 @@ namespace dr553 {
 }
 
 // dr554: na
+
+// dr555: na
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Endilll wrote:

I added a proper test for 555. Basically, I copied 466 test, and derived reference tests from it. In 466, I derived a test for non-pointer and non-reference scalar types.

> Finally, there is no place in the Standard that describes the lookup for pseudo-destructor calls of the form p->T::~T() and r.T::~T(), where p and r are a pointer and reference to scalar, respectively.

As we agreed offline, I'm testing just this sentence from 555, as that's the only actionable thing there for us.

https://github.com/llvm/llvm-project/pull/87909