Author: Pavel Labath Date: 2020-03-30T16:00:21+02:00 New Revision: 7b00eeb53de06c7979fd2a88436c3387d0492ee8
URL: https://github.com/llvm/llvm-project/commit/7b00eeb53de06c7979fd2a88436c3387d0492ee8 DIFF: https://github.com/llvm/llvm-project/commit/7b00eeb53de06c7979fd2a88436c3387d0492ee8.diff LOG: [lldb] Fix another crash in covariant type handling Summary: D73024 seems to have fixed one set crash, but it introduced another. Namely, if a class contains a covariant method returning itself, the logic in MaybeCompleteReturnType could cause us to attempt a recursive import, which would result in an assertion failure in clang::DeclContext::removeDecl. For some reason, this only manifested itself if the class contained at least two member variables, and the class itself was imported as a result of a recursive covariant import. This patch fixes the crash by not attempting to import classes which are already completed in MaybeCompleteReturnType. However, it's not clear to me if this is the right fix, or if this should be handled automatically by functions lower in the stack. Reviewers: teemperor, shafik Subscribers: lldb-commits Tags: #lldb Differential Revision: https://reviews.llvm.org/D76840 Added: Modified: lldb/source/Plugins/ExpressionParser/Clang/ClangASTImporter.cpp lldb/test/API/lang/cpp/covariant-return-types/TestCovariantReturnTypes.py lldb/test/API/lang/cpp/covariant-return-types/main.cpp Removed: ################################################################################ diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangASTImporter.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangASTImporter.cpp index 479cb64deefd..4b3e237dc62c 100644 --- a/lldb/source/Plugins/ExpressionParser/Clang/ClangASTImporter.cpp +++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangASTImporter.cpp @@ -997,6 +997,8 @@ static void MaybeCompleteReturnType(ClangASTImporter &importer, clang::RecordDecl *rd = return_type->getPointeeType()->getAsRecordDecl(); if (!rd) return; + if (rd->getDefinition()) + return; importer.CompleteTagDecl(rd); } diff --git a/lldb/test/API/lang/cpp/covariant-return-types/TestCovariantReturnTypes.py b/lldb/test/API/lang/cpp/covariant-return-types/TestCovariantReturnTypes.py index 86a6ddd6e47b..6f2b3eafd2e9 100644 --- a/lldb/test/API/lang/cpp/covariant-return-types/TestCovariantReturnTypes.py +++ b/lldb/test/API/lang/cpp/covariant-return-types/TestCovariantReturnTypes.py @@ -38,3 +38,5 @@ def test(self): self.expect_expr("derived.getOtherRef().value()", result_summary='"derived"') self.expect_expr("base_ptr_to_derived->getOtherRef().value()", result_summary='"derived"') self.expect_expr("base.getOtherRef().value()", result_summary='"base"') + + self.expect_expr("referencing_derived.getOther()->get()->a", result_value='42') diff --git a/lldb/test/API/lang/cpp/covariant-return-types/main.cpp b/lldb/test/API/lang/cpp/covariant-return-types/main.cpp index 2a6fc682c39a..ea05043d6cf9 100644 --- a/lldb/test/API/lang/cpp/covariant-return-types/main.cpp +++ b/lldb/test/API/lang/cpp/covariant-return-types/main.cpp @@ -28,6 +28,23 @@ struct Derived : public Base { OtherDerived& getOtherRef() override { return other_derived; } }; +// A regression test for a class with at least two members containing a +// covariant function, which is referenced through another covariant function. +struct BaseWithMembers { + int a = 42; + int b = 47; + virtual BaseWithMembers *get() { return this; } +}; +struct DerivedWithMembers: BaseWithMembers { + DerivedWithMembers *get() override { return this; } +}; +struct ReferencingBase { + virtual BaseWithMembers *getOther() { return new BaseWithMembers(); } +}; +struct ReferencingDerived: ReferencingBase { + DerivedWithMembers *getOther() { return new DerivedWithMembers(); } +}; + int main() { Derived derived; Base base; @@ -36,5 +53,7 @@ int main() { (void)base_ptr_to_derived->getRef(); (void)base_ptr_to_derived->getOtherPtr(); (void)base_ptr_to_derived->getOtherRef(); + + ReferencingDerived referencing_derived; return 0; // break here } _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
