Author: epilk Date: Thu Jul 19 13:40:20 2018 New Revision: 337497 URL: http://llvm.org/viewvc/llvm-project?rev=337497&view=rev Log: [Sema] Diagnose an invalid dependent function template specialization
Previously, clang marked the specialization as invalid without emitting a diagnostic. This lead to an assert in CodeGen. rdar://41806724 Differential revision: https://reviews.llvm.org/D49085 Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td cfe/trunk/lib/Sema/SemaTemplate.cpp cfe/trunk/test/CXX/temp/temp.decls/temp.friend/p1.cpp Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=337497&r1=337496&r2=337497&view=diff ============================================================================== --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original) +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Thu Jul 19 13:40:20 2018 @@ -4106,6 +4106,13 @@ def ext_explicit_specialization_storage_ def err_explicit_specialization_inconsistent_storage_class : Error< "explicit specialization has extraneous, inconsistent storage class " "'%select{none|extern|static|__private_extern__|auto|register}0'">; +def err_dependent_function_template_spec_no_match : Error< + "no candidate function template was found for dependent" + " friend function template specialization">; +def note_dependent_function_template_spec_discard_reason : Note< + "candidate ignored: %select{not a function template" + "|not a member of the enclosing namespace;" + " did you mean to explicitly qualify the specialization?}0">; // C++ class template specializations and out-of-line definitions def err_template_spec_needs_header : Error< Modified: cfe/trunk/lib/Sema/SemaTemplate.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplate.cpp?rev=337497&r1=337496&r2=337497&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaTemplate.cpp (original) +++ cfe/trunk/lib/Sema/SemaTemplate.cpp Thu Jul 19 13:40:20 2018 @@ -8003,17 +8003,34 @@ Sema::CheckDependentFunctionTemplateSpec // the correct context. DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); LookupResult::Filter F = Previous.makeFilter(); + enum DiscardReason { NotAFunctionTemplate, NotAMemberOfEnclosing }; + SmallVector<std::pair<DiscardReason, Decl *>, 8> DiscardedCandidates; while (F.hasNext()) { NamedDecl *D = F.next()->getUnderlyingDecl(); - if (!isa<FunctionTemplateDecl>(D) || - !FDLookupContext->InEnclosingNamespaceSetOf( - D->getDeclContext()->getRedeclContext())) + if (!isa<FunctionTemplateDecl>(D)) { F.erase(); + DiscardedCandidates.push_back(std::make_pair(NotAFunctionTemplate, D)); + continue; + } + + if (!FDLookupContext->InEnclosingNamespaceSetOf( + D->getDeclContext()->getRedeclContext())) { + F.erase(); + DiscardedCandidates.push_back(std::make_pair(NotAMemberOfEnclosing, D)); + continue; + } } F.done(); - // Should this be diagnosed here? - if (Previous.empty()) return true; + if (Previous.empty()) { + Diag(FD->getLocation(), + diag::err_dependent_function_template_spec_no_match); + for (auto &P : DiscardedCandidates) + Diag(P.second->getLocation(), + diag::note_dependent_function_template_spec_discard_reason) + << P.first; + return true; + } FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), ExplicitTemplateArgs); Modified: cfe/trunk/test/CXX/temp/temp.decls/temp.friend/p1.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CXX/temp/temp.decls/temp.friend/p1.cpp?rev=337497&r1=337496&r2=337497&view=diff ============================================================================== --- cfe/trunk/test/CXX/temp/temp.decls/temp.friend/p1.cpp (original) +++ cfe/trunk/test/CXX/temp/temp.decls/temp.friend/p1.cpp Thu Jul 19 13:40:20 2018 @@ -359,3 +359,31 @@ namespace PR10913 { template void f2<int>(X<int> *); template void f2<float>(X<int> *); // expected-note{{in instantiation of function template specialization 'PR10913::f2<float, int>' requested here}} } + +namespace test16 { +template <class T> struct foo {}; // expected-note{{candidate ignored: not a function template}} +template <class T> class A { + friend void foo<T>(); // expected-error{{no candidate function template was found for dependent friend function template specialization}} +}; +} + +namespace test17 { +namespace ns { +template <class T> void foo() {} // expected-note{{candidate ignored: not a member of the enclosing namespace; did you mean to explicitly qualify the specialization?}} +} +using ns::foo; +template <class T> struct A { + friend void foo<T>() {} // expected-error{{no candidate function template was found for dependent friend function template specialization}} +}; +} + +namespace test18 { +namespace ns1 { template <class T> struct foo {}; } // expected-note{{candidate ignored: not a function template}} +namespace ns2 { void foo() {} } // expected-note{{candidate ignored: not a function template}} +using ns1::foo; +using ns2::foo; + +template <class T> class A { + friend void foo<T>() {} // expected-error{{no candidate function template was found for dependent friend function template specialization}} +}; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits