[clang] [Clang][Parser] Accept P2741R3 (static_assert with user-generated message) in C++11 as an extension (PR #102044)

[via cfe-commits]

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@@ -671,10 +671,8 @@ static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts,
                         LangOpts.CPlusPlus23   ? "202211L"
                         : LangOpts.CPlusPlus17 ? "201603L"
                                                : "200907");
-    Builder.defineMacro("__cpp_static_assert", LangOpts.CPlusPlus26 ? "202306L"
-                                               : LangOpts.CPlusPlus17
-                                                   ? "201411L"
-                                                   : "200410");
+    // C++17 / C++26 static_assert backported
+    Builder.defineMacro("__cpp_static_assert", "202306L");
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cor3ntin wrote:

We have had that discussion before. https://github.com/llvm/llvm-project/issues/77262

I think we should
 * unconditionally set the value of __cpp_static_assert to 202306L in this patch
 * Explore through an rfc or more detailed issue an holistic change of there is consensus that we should improve how pedantic errors and feature test macro interact.





https://github.com/llvm/llvm-project/pull/102044