[PATCH] D56160: [clang-tidy] modernize-use-trailing-return check

[Jonas Toth via Phabricator via cfe-commits]

JonasToth added a comment.

In D56160#1367074 <https://reviews.llvm.org/D56160#1367074>, @bernhardmgruber wrote:

> Thank you again @JonasToth for all your valueable input! I could almost successfully run my check on the llvm/lib subfolder. I created a compilation database from within Visual Studio using an extension called SourceTrail <https://www.sourcetrail.com/blog/export_clang_compilation_database_from_visual_studio_solution/>. One of the issues was the following:


Very good!

>   struct Object { long long value; };
>   class C {
>     int Object;
>     struct Object m();
>   };
>   Object C::m() { return {0}; }
> 
> 
> If I rewrite this to the following
> 
>   struct Object { long long value; };
>   class C {
>     int Object;
>     struct Object m();
>   };
>   auto C::m() -> Object { return {0}; }
> 
> 
> a compilation error occurs afterwards, because Object now refers to the class member. I discovered a similar problem colliding with the name of a function argument. So essentially, I believe I now require a name lookup of the return type (if it is unqualified) in the scope of the function. In case such a name already exists, i have to prefix `struct/class` or perform no replacement. I looked at the documentation of `ASTContext`, but it seems all the good stuff is in `DeclContext`, which I have not available. How can I perform a name lookup inside the `check` member function?

That is very interesting and I was not aware of this possibility :D

Every `Decl` derives from `DeclContext`, see for example the docs for `CXXMethodDecl` (https://clang.llvm.org/doxygen/classclang_1_1CXXMethodDecl.html)
You should be able to look up the names you are interested. I don't know of a good way to check for the issue we have right now, @aaron.ballman knows that probably better then I do.
Try to experiment, but If you don't find a solution come back to us, we will figure something out (or ask in IRC).


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  https://reviews.llvm.org/D56160/new/

https://reviews.llvm.org/D56160