Quuxplusone added inline comments.
================ Comment at: clang/lib/AST/ASTImporter.cpp:1152 + if (Error E = importSeq(ToElementType, ToSizeExpr)) + return std::move(E); ---------------- martong wrote: > Quuxplusone wrote: > > As the author of [P1155 "More Implicit Move"](https://wg21.link/p1155), I > > would expect that you don't need `return std::move(E)` — `return E` should > > just as well perform "implicit move" in C++11 and later, assuming that > > `llvm::Expected<QualType>` has a valid constructor from `llvm::Error&&`. > > > > You're not seeing any compiler diagnostic that //suggests// you use > > `std::move` here, are you? > I have some vague and obscure memory about that GCC 4.8 (or 5.2) required > explicitly the && cast, otherwise we had a diagnostic (@gamesh411 maybe you > help me to recall that?) Ah, you are absolutely correct: GCC 4.9.4 does not do implicit move in this situation, whereas GCC 5.1 and later do do it. https://godbolt.org/z/YDHtTH I didn't realize that portability back to GCC 4.9 was still a concern for LLVM/Clang. If it is, then please feel free to keep the `std::move` here and throughout (but maybe mention it in the commit message for the benefit of others who might think as I did). If portability back to pre-GCC-5 is //not// a concern, then I would continue to recommend removing the `std::move`. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D73675/new/ https://reviews.llvm.org/D73675 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
