[PATCH] D105478: [clang] Make CXXRecrdDecl invalid if it contains any undeduced fields.

[Adam Czachorowski via Phabricator via cfe-commits]

adamcz added inline comments.


================
Comment at: clang/test/SemaCXX/cxx11-crashes.cpp:117
+  // The missing expression makes A undeduced.
+  static constexpr auto A = ;  // expected-error {{expected expression}}
+  Foo<decltype(A)>::type B;  // The type of B is also undeduced (wrapped in Elaborated).
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hokein wrote:
> I think the root cause is that this incomplete var declaration is marked valid.
> 
> Looks like there are a few inconsistencies in clang:
> 
> ```
> struct Bar {
>   static constexpr auto A1; // case1: invalid
>   static constexpr auto A2 = ; // case2: valid
> };
> 
> // static var decl in global context
> static constexpr auto A3; // case3: invalid
> static constexpr auto A4 = ; // case4: invalid
> ```
> 
> so it looks like marking case2 valid is a bug, I think we should invalidate it.
I updated the change to mark a FieldDecl with undeduced type as invalid, thus making the record invalid too. Also added a test using -ast-dump to verify that both field and record are invalid, but kept the crash test too.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D105478/new/

https://reviews.llvm.org/D105478