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

[Richard Smith via cfe-commits]

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@@ -74,6 +74,22 @@ C++ Specific Potentially Breaking Changes
     template <typename T>
     void f();
 
+- During constant evaluation, comparisons between different evaluations of the
+  same string literal are now correctly treated as non-constant, and comparisons
+  between string literals that cannot possibly overlap in memory are now treated
+  as constant.
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zygoloid wrote:

Done.

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