[clang] [Clang] Add flags and lang option for C++2d (PR #203992)

[Corentin Jabot via cfe-commits]

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@@ -7533,9 +7533,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                              // TransferableCommand::tryParseStdArg() in
                              // lib/Tooling/InterpolatingCompilationDatabase.cpp
                              // to match.
-                             // TODO add c++23 and c++26 when MSVC supports it.
+                             // TODO add c++23, c++26, c++29 when MSVC supports
+                             // it.
                              .Case("c++23preview", "-std=c++23")
-                             .Case("c++latest", "-std=c++26")
+                             .Case("c++latest", "-std=c++29")
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cor3ntin wrote:

Thanks - 

For /std:c++26preview, it will have to be another PR but we can certainly make that happen for clang 23!

https://github.com/llvm/llvm-project/pull/203992