[clang] [clang] implement current direction of CWG2765 for string literal comparisons in constant evaluation (PR #109208)

[Timm Baeder via cfe-commits]

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@@ -96,6 +96,8 @@ def note_constexpr_pointer_constant_comparison : Note<
   "at runtime">;
 def note_constexpr_literal_comparison : Note<
   "comparison of addresses of literals has unspecified value">;
+def note_constexpr_opaque_call_comparison : Note<
+  "comparison against opaque constant has unspecified value">;
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tbaederr wrote:

I can't imagine a normal person knows what's meant by "opaque constant"

https://github.com/llvm/llvm-project/pull/109208