[PATCH] D78404: [clang] Implement P0692R1 from C++20 (access checking on specializations)

[Sergej Jaskiewicz via Phabricator via cfe-commits]

broadwaylamb marked 3 inline comments as done.
broadwaylamb added inline comments.


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Comment at: clang/include/clang/AST/Decl.h:3198
 /// alias-declaration.
-class TypeAliasDecl : public TypedefNameDecl {
+class TypeAliasDecl : public TypedefNameDecl, public DeclContext {
   /// The template for which this is the pattern, if any.
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I'm not sure about inheriting `TypeAliasDecl` from `DeclContext`, but (see below)


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Comment at: clang/lib/Parse/ParseTemplate.cpp:211
+    Decl *Decl = usingDeclPtr.get().getSingleDecl();
+    ParsingDeclRAII.complete(Decl);
+    return Decl;
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…but otherwise I couldn't make it print access level diagnostics for a particular kind of `using` declaration template (see in the next inline comment).

Why? Because of [this line](https://github.com/llvm/llvm-project/blob/8e0c9e21bf5f3e7a427b07e3eaf3bc80d2c74cb6/clang/lib/Sema/SemaAccess.cpp#L1479) — we need to be able to cast the `TypeAliasDecl` to `DeclContext` in order for delayed access check to be actually performed.


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Comment at: clang/test/CXX/temp/temp.decls/temp.class.spec/p10.cpp:58
+template <typename T>
+using alias3_1 = TemplateClass3<T, &TestClass::func>;
+
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I'm talking about declarations like this.

Previously, we didn't reject it (which I believe was incorrect), and now we do.


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  https://reviews.llvm.org/D78404/new/

https://reviews.llvm.org/D78404