Author: ahatanak Date: Tue Sep 13 17:13:02 2016 New Revision: 281405 URL: http://llvm.org/viewvc/llvm-project?rev=281405&view=rev Log: [CodeGen] Fix an assert in EmitNullConstant.
r235815 changed CGRecordLowering::accumulateBases to ignore non-virtual bases of size 0, which prevented adding those non-virtual bases to CGRecordLayout's NonVirtualBases. This caused clang to assert when CGRecordLayout::getNonVirtualBaseLLVMFieldNo was called in EmitNullConstant. This commit fixes the bug by ignoring zero-sized non-virtual bases in EmitNullConstant. rdar://problem/28100139 Differential Revision: https://reviews.llvm.org/D24312 Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp cfe/trunk/test/CodeGenCXX/empty-classes.cpp Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprConstant.cpp?rev=281405&r1=281404&r2=281405&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CGExprConstant.cpp (original) +++ cfe/trunk/lib/CodeGen/CGExprConstant.cpp Tue Sep 13 17:13:02 2016 @@ -1532,7 +1532,8 @@ static llvm::Constant *EmitNullConstant( cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl()); // Ignore empty bases. - if (base->isEmpty()) + if (base->isEmpty() || + CGM.getContext().getASTRecordLayout(base).getNonVirtualSize().isZero()) continue; unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); Modified: cfe/trunk/test/CodeGenCXX/empty-classes.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/empty-classes.cpp?rev=281405&r1=281404&r2=281405&view=diff ============================================================================== --- cfe/trunk/test/CodeGenCXX/empty-classes.cpp (original) +++ cfe/trunk/test/CodeGenCXX/empty-classes.cpp Tue Sep 13 17:13:02 2016 @@ -96,3 +96,24 @@ namespace rdar20621065 { // Type checked at the top of the file. B b; }; + +// This test used to crash when CGRecordLayout::getNonVirtualBaseLLVMFieldNo was called. +namespace record_layout { +struct X0 { + int x[0]; +}; + +template<typename> +struct X2 : X0 { +}; + +template<typename> +struct X3 : X2<int> { + X3() : X2<int>() {} +}; + + +void test0() { + X3<int>(); +} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
