[PATCH] D146764: [clang] Make predefined expressions string literals under -fms-extensions

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman requested changes to this revision.
aaron.ballman added a comment.
This revision now requires changes to proceed.

This should also have a release note, eventually.



================
Comment at: clang/lib/Sema/SemaExpr.cpp:3586-3591
+  // MSVC treats all predefined expressions as string literals rather than char
+  // arrays.
+  if (LangOpts.MicrosoftExt)
+    return SL;
+
   return PredefinedExpr::Create(Context, Loc, ResTy, IK, SL);
----------------
This is incorrect -- these are still predefined expressions even if they're a string literal. Otherwise, we lose AST fidelity and things like the `predefinedExpr()` AST matcher don't work (https://github.com/llvm/llvm-project/blob/main/clang/include/clang/ASTMatchers/ASTMatchers.h#L2697), and `-ast-print` will print the wrong thing (https://github.com/llvm/llvm-project/blob/main/clang/lib/AST/StmtPrinter.cpp#L1248).


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D146764/new/

https://reviews.llvm.org/D146764