Author: Chuanqi Xu Date: 2022-01-11T10:16:26+08:00 New Revision: d9d63fc1088c22129cde9c3d3a84f356c875190e
URL: https://github.com/llvm/llvm-project/commit/d9d63fc1088c22129cde9c3d3a84f356c875190e DIFF: https://github.com/llvm/llvm-project/commit/d9d63fc1088c22129cde9c3d3a84f356c875190e.diff LOG: [AST] lookup in parent DeclContext for transparent DeclContext The compiler would crash if we lookup for name in transparent decl context. See the tests attached for example. I think this should make sense since the member declared in transparent DeclContext are semantically defined in the enclosing (non-transparent) DeclContext, this is the definition for transparent DeclContext. Reviewed By: erichkeane Differential Revision: https://reviews.llvm.org/D116792 Added: clang/test/Modules/Inputs/template_name_lookup/foo.cppm clang/test/Modules/template_name_lookup.cpp clang/test/SemaCXX/lookup-template-name-extern-CXX.cpp Modified: clang/lib/AST/DeclBase.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp index 52b8a45721105..98a5c6b664713 100644 --- a/clang/lib/AST/DeclBase.cpp +++ b/clang/lib/AST/DeclBase.cpp @@ -1644,9 +1644,9 @@ void DeclContext::buildLookupImpl(DeclContext *DCtx, bool Internal) { DeclContext::lookup_result DeclContext::lookup(DeclarationName Name) const { - assert(getDeclKind() != Decl::LinkageSpec && - getDeclKind() != Decl::Export && - "should not perform lookups into transparent contexts"); + // For transparent DeclContext, we should lookup in their enclosing context. + if (getDeclKind() == Decl::LinkageSpec || getDeclKind() == Decl::Export) + return getParent()->lookup(Name); const DeclContext *PrimaryContext = getPrimaryContext(); if (PrimaryContext != this) diff --git a/clang/test/Modules/Inputs/template_name_lookup/foo.cppm b/clang/test/Modules/Inputs/template_name_lookup/foo.cppm new file mode 100644 index 0000000000000..ee1973f65e716 --- /dev/null +++ b/clang/test/Modules/Inputs/template_name_lookup/foo.cppm @@ -0,0 +1,3 @@ +export module foo; +export template <typename T> +class X {}; diff --git a/clang/test/Modules/template_name_lookup.cpp b/clang/test/Modules/template_name_lookup.cpp new file mode 100644 index 0000000000000..29375e514025f --- /dev/null +++ b/clang/test/Modules/template_name_lookup.cpp @@ -0,0 +1,11 @@ +// RUN: rm -rf %t +// RUN: mkdir -p %t +// RUN: %clang_cc1 -std=c++20 %S/Inputs/template_name_lookup/foo.cppm -emit-module-interface -o %t/foo.pcm +// RUN: %clang_cc1 -std=c++20 -fprebuilt-module-path=%t %s -fsyntax-only -verify + +import foo; +void use() { + X x; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'X'}} + // expected-note@Inputs/template_name_lookup/foo.cppm:3 {{candidate template ignored: couldn't infer template argument 'T'}} + // expected-note@Inputs/template_name_lookup/foo.cppm:3 {{candidate function template not viable: requires 1 argument, but 0 were provided}} +} diff --git a/clang/test/SemaCXX/lookup-template-name-extern-CXX.cpp b/clang/test/SemaCXX/lookup-template-name-extern-CXX.cpp new file mode 100644 index 0000000000000..93e7fb6199354 --- /dev/null +++ b/clang/test/SemaCXX/lookup-template-name-extern-CXX.cpp @@ -0,0 +1,12 @@ +// Tests that the lookup in transparent declaration context +// (linkage specifiaction context) wouldn't cause compiler crash. +// RUN: %clang_cc1 -std=c++20 %s -fsyntax-only -verify +extern "C++" { +template <class T> +class X {}; // expected-note {{candidate template ignored: couldn't infer template argument 'T'}} + // expected-note@-1 {{candidate function template not viable: requires 1 argument, but 0 were provided}} +} + +void foo() { + X x; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'X'}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
