Author: Gábor Spaits Date: 2024-10-15T10:19:17+02:00 New Revision: 48521209aa4d95a97564f8a5af7ccca09c6ede5d
URL: https://github.com/llvm/llvm-project/commit/48521209aa4d95a97564f8a5af7ccca09c6ede5d DIFF: https://github.com/llvm/llvm-project/commit/48521209aa4d95a97564f8a5af7ccca09c6ede5d.diff LOG: [Sema]Use tag name lookup for class names (#112166) This PR would fix #16855 . The correct lookup to use for class names is Tag name lookup, because it does not take namespaces into account. The lookup before does and because of this some valid programs are not accepted. An example scenario of a valid program being declined is when you have a struct (let's call it `y`) inheriting from another struct with a name `x` but the struct `y` is in a namespace that is also called `x`: ``` struct x {}; namespace { namespace x { struct y : x {}; } } ``` This shall be accepted because: ``` C++ [class.derived]p2 (wrt lookup in a base-specifier): The lookup for // the component name of the type-name or simple-template-id is type-only. ``` Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaDecl.cpp clang/test/CXX/class.derived/p2.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 7ec13aa7af1abc..817e3abef8d566 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -516,6 +516,7 @@ Bug Fixes to C++ Support - Fixed a bug in lambda captures where ``constexpr`` class-type objects were not properly considered ODR-used in certain situations. (#GH47400), (#GH90896) - Fix erroneous templated array size calculation leading to crashes in generated code. (#GH41441) +- During the lookup for a base class name, non-type names are ignored. (#GH16855) Bug Fixes to AST Handling ^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index 40456bbf5d44bf..fece22c663d00c 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -357,10 +357,13 @@ ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc, return nullptr; } - // FIXME: LookupNestedNameSpecifierName isn't the right kind of - // lookup for class-names. - LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : - LookupOrdinaryName; + // In the case where we know that the identifier is a class name, we know that + // it is a type declaration (struct, class, union or enum) so we can use tag + // name lookup. + // + // C++ [class.derived]p2 (wrt lookup in a base-specifier): The lookup for + // the component name of the type-name or simple-template-id is type-only. + LookupNameKind Kind = isClassName ? LookupTagName : LookupOrdinaryName; LookupResult Result(*this, &II, NameLoc, Kind); if (LookupCtx) { // Perform "qualified" name lookup into the declaration context we diff --git a/clang/test/CXX/class.derived/p2.cpp b/clang/test/CXX/class.derived/p2.cpp index 87e0f748615456..401ee37ad6b64c 100644 --- a/clang/test/CXX/class.derived/p2.cpp +++ b/clang/test/CXX/class.derived/p2.cpp @@ -6,4 +6,16 @@ namespace PR5840 { struct Base {}; int Base = 10; struct Derived : Base {}; -} +} // namespace PR5840 + +namespace issue_16855 { + struct x {}; + namespace + { + namespace x + { + struct y : x + {}; + } // namespace x + } +} // namespace issue_16855 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
