llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: None (keinflue) <details> <summary>Changes</summary> This modifies InjectAnonymousStructOrUnionMembers to inject an IndirectFieldDecl and mark it invalid even if its name conflicts with another name in the scope. This resolves a crash on a further diagnostic diag::err_multiple_mem_union_initialization which via findDefaultInitializer relies on these declarations being present. Fixes #<!-- -->149985 --- Full diff: https://github.com/llvm/llvm-project/pull/153140.diff 4 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+2) - (modified) clang/lib/Sema/SemaDecl.cpp (+32-28) - (modified) clang/test/CXX/class/class.mem/p13.cpp (+1-1) - (modified) clang/test/CXX/class/class.union/class.union.anon/p4.cpp (+10) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 0e9fcaa5fac6a..00b21471f3731 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -184,6 +184,8 @@ Bug Fixes to C++ Support (``[[assume(expr)]]``) creates temporary objects. - Fix the dynamic_cast to final class optimization to correctly handle casts that are guaranteed to fail (#GH137518). +- Fix a crash if errors "member of anonymous [...] redeclares" and + "intializing multiple members of union" coincide (#GH149985). Bug Fixes to AST Handling ^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index b5eb825eb52cc..052e026fa3ee3 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -5463,40 +5463,44 @@ InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner, // distinct from the names of any other entity in the // scope in which the anonymous union is declared. Invalid = true; - } else { - // C++ [class.union]p2: - // For the purpose of name lookup, after the anonymous union - // definition, the members of the anonymous union are - // considered to have been defined in the scope in which the - // anonymous union is declared. - unsigned OldChainingSize = Chaining.size(); - if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) - Chaining.append(IF->chain_begin(), IF->chain_end()); - else - Chaining.push_back(VD); + } + // Inject the IndirectFieldDecl even if invalid, because later + // diagnostics may depend on it being present. + + // C++ [class.union]p2: + // For the purpose of name lookup, after the anonymous union + // definition, the members of the anonymous union are + // considered to have been defined in the scope in which the + // anonymous union is declared. + unsigned OldChainingSize = Chaining.size(); + if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) + Chaining.append(IF->chain_begin(), IF->chain_end()); + else + Chaining.push_back(VD); - assert(Chaining.size() >= 2); - NamedDecl **NamedChain = - new (SemaRef.Context)NamedDecl*[Chaining.size()]; - for (unsigned i = 0; i < Chaining.size(); i++) - NamedChain[i] = Chaining[i]; + assert(Chaining.size() >= 2); + NamedDecl **NamedChain = + new (SemaRef.Context) NamedDecl *[Chaining.size()]; + for (unsigned i = 0; i < Chaining.size(); i++) + NamedChain[i] = Chaining[i]; - IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create( - SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(), - VD->getType(), {NamedChain, Chaining.size()}); + IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create( + SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(), + VD->getType(), {NamedChain, Chaining.size()}); - for (const auto *Attr : VD->attrs()) - IndirectField->addAttr(Attr->clone(SemaRef.Context)); + for (const auto *Attr : VD->attrs()) + IndirectField->addAttr(Attr->clone(SemaRef.Context)); - IndirectField->setAccess(AS); - IndirectField->setImplicit(); - SemaRef.PushOnScopeChains(IndirectField, S); + IndirectField->setAccess(AS); + IndirectField->setImplicit(); + IndirectField->setInvalidDecl(Invalid); + SemaRef.PushOnScopeChains(IndirectField, S); - // That includes picking up the appropriate access specifier. - if (AS != AS_none) IndirectField->setAccess(AS); + // That includes picking up the appropriate access specifier. + if (AS != AS_none) + IndirectField->setAccess(AS); - Chaining.resize(OldChainingSize); - } + Chaining.resize(OldChainingSize); } } diff --git a/clang/test/CXX/class/class.mem/p13.cpp b/clang/test/CXX/class/class.mem/p13.cpp index d947586c41940..4dc959cd0beb8 100644 --- a/clang/test/CXX/class/class.mem/p13.cpp +++ b/clang/test/CXX/class/class.mem/p13.cpp @@ -63,7 +63,7 @@ struct X4 { // expected-note{{previous}} int X; union { float Y; - unsigned X4; // expected-error{{redeclares 'X4'}} + unsigned X4; // expected-error{{redeclares 'X4'}} expected-error {{'X4' has the same name as its class}} }; }; }; diff --git a/clang/test/CXX/class/class.union/class.union.anon/p4.cpp b/clang/test/CXX/class/class.union/class.union.anon/p4.cpp index a12ec38503fa8..710636d2235db 100644 --- a/clang/test/CXX/class/class.union/class.union.anon/p4.cpp +++ b/clang/test/CXX/class/class.union/class.union.anon/p4.cpp @@ -8,3 +8,13 @@ union U { int y = 1; // expected-error {{initializing multiple members of union}} }; }; + +namespace GH149985 { + union U { + int x; // expected-note {{previous declaration is here}} + union { + int x = {}; // expected-error {{member of anonymous union redeclares}} expected-note {{previous initialization is here}} + }; + int y = {}; // expected-error {{initializing multiple members of union}} + }; +} `````````` </details> https://github.com/llvm/llvm-project/pull/153140 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
