[clang] [Clang] [C++26] Implement P2573R2: `= delete("should have a reason");` (PR #86526)

[via cfe-commits]

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@@ -750,6 +750,9 @@ static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts,
   Builder.defineMacro("__cpp_named_character_escapes", "202207L");
   Builder.defineMacro("__cpp_placeholder_variables", "202306L");
 
+  // C++26 features supported in earlier language modes.
+  Builder.defineMacro("__cpp_deleted_function", "202403L");
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cor3ntin wrote:

You should modify LanguageExtensions.rst

https://github.com/llvm/llvm-project/pull/86526