[PATCH] D73675: Avoid many std::tie/tuple instantiations in ASTImporter

[Gabor Marton via Phabricator via cfe-commits]

martong added a subscriber: gamesh411.
martong added inline comments.


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Comment at: clang/lib/AST/ASTImporter.cpp:1152
+  if (Error E = importSeq(ToElementType, ToSizeExpr))
+    return std::move(E);
 
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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?)


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https://reviews.llvm.org/D73675