[clang] [Clang] use parent declaration context to avoid asserting cast failure in defaulted comparison method (PR #96228)

[Shafik Yaghmour via cfe-commits]

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@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s
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shafik wrote:

I think this is a better location for the test:

https://github.com/llvm/llvm-project/blob/main/clang/test/CXX/class/class.compare/class.compare.default/p1.cpp

We normally wrap tests in a namespace starting with `GH` and then the issue number, for this case `namespace GH96043`.

https://github.com/llvm/llvm-project/pull/96228