[PATCH] D141569: [clang-tidy] Implement CppCoreGuideline F.18

[Chris Cotter via Phabricator via cfe-commits]

ccotter added inline comments.


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Comment at: clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/rvalue-reference-param-not-moved.cpp:301
+  }
+  void never_moves(T&& t) {}
+  // CHECK-MESSAGES: :[[@LINE-1]]:24: warning: rvalue reference parameter 't' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
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PiotrZSL wrote:
> that's not always rvalue, if T would be for example int&, then this going to be lvalue...
Looking at the rule enforcement, I might have overlooked one thing:

 > Flag all X&& parameters (where X is not a template type parameter name) where the function body uses them without std::move.

I think this means this code should not be flagged, even if `T` is an object which is cheap to move but expensive to copy (and not a reference to that type). I would like for `AClassTemplate<LargeObject>` to be flagged, but not `AClassTemplate<LargeObject&>`, so let me look into this to see if I can limit this to instantiations of the type, rather than looking at the template definition itself.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D141569/new/

https://reviews.llvm.org/D141569