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Assertion failure/bad codegen: too many args w/inherited constructor from virtual base in ctor-initializer #33749

Open hubert-reinterpretcast opened 7 years ago

hubert-reinterpretcast commented 7 years ago
Bugzilla Link 34401
Version trunk
OS All
CC @AaronBallman

Extended Description

When a mem-initializer selects an inherited constructor from a virtual base and the object it constructs is not a complete object, Clang tries to pass more arguments than it should.

SOURCE (<stdin>):

struct V { V() = default; V(int); };
struct A : virtual V {
  using V::V;
  A() : A(19) { }
};
struct B : A { } b;

COMPILER INVOCATION:

clang++ -cc1 -xc++ -std=c++1z -emit-llvm -

EXPECTED OUTPUT:

(Clean compile)

ACTUAL OUTPUT:

clang++: /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGCall.cpp:4112: clang::CodeGen::RValue clang::CodeGen::CodeGenFunction::EmitCall(const clang::CodeGen::CGFunctionInfo&, const clang::CodeGen::CGCallee&, clang::CodeGen::ReturnValueSlot, const clang::CodeGen::CallArgList&, llvm::Instruction**): Assertion `IRCallArgs.size() == IRFuncTy->getNumParams() || IRFuncTy->isVarArg()' failed.
#0 0x000000001481a998 llvm::sys::PrintStackTrace(llvm::raw_ostream&) /llvm_trunk/llvm/lib/Support/Unix/Signals.inc:398:0
#1 0x000000001481aa9c PrintStackTraceSignalHandler(void*) /llvm_trunk/llvm/lib/Support/Unix/Signals.inc:461:0
#2 0x000000001481877c llvm::sys::RunSignalHandlers() /llvm_trunk/llvm/lib/Support/Signals.cpp:50:0
#3 0x0000000014819f40 SignalHandler(int) /llvm_trunk/llvm/lib/Support/Unix/Signals.inc:242:0
#4 0x00003fff840e0478  0x478 __GI_abort
#5 0x00003fff840e0478
#6 0x00003fff840e0478 __assert_fail_base (+0x478)
#7 0x00003fff83b30d70 __GI___assert_fail (/lib64/libc.so.6+0x40d70)
#8 0x00003fff83b248a4 clang::CodeGen::CodeGenFunction::EmitCall(clang::CodeGen::CGFunctionInfo const&, clang::CodeGen::CGCallee const&, clang::CodeGen::ReturnValueSlot, clang::CodeGen::CallArgList const&, llvm::Instruction**) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGCall.cpp:4112:0
#9 0x00003fff83b24994 clang::CodeGen::CodeGenFunction::EmitCXXConstructorCall(clang::CXXConstructorDecl const*, clang::CXXCtorType, bool, bool, clang::CodeGen::Address, clang::CodeGen::CallArgList&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGClass.cpp:2061:0
#10 0x0000000015057448 clang::CodeGen::CodeGenFunction::EmitCXXConstructorCall(clang::CXXConstructorDecl const*, clang::CXXCtorType, bool, bool, clang::CodeGen::Address, clang::CXXConstructExpr const*) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGClass.cpp:1979:0
#11 0x0000000015080cd4 clang::CodeGen::CodeGenFunction::EmitCXXConstructExpr(clang::CXXConstructExpr const*, clang::CodeGen::AggValueSlot) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGExprCXX.cpp:622:0
#12 0x0000000015080518 (anonymous namespace)::AggExprEmitter::VisitCXXConstructExpr(clang::CXXConstructExpr const*) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGExprAgg.cpp:1001:0
#13 0x000000001511be9c clang::StmtVisitorBase<clang::make_ptr, (anonymous namespace)::AggExprEmitter, void>::Visit(clang::Stmt*) /tools/clang/include/clang/AST/StmtNodes.inc:213:0
#14 0x000000001510c0a8 (anonymous namespace)::AggExprEmitter::Visit(clang::Expr*) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGExprAgg.cpp:104:0
#15 0x00000000151103d0 clang::CodeGen::CodeGenFunction::EmitAggExpr(clang::Expr const*, clang::CodeGen::AggValueSlot) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGExprAgg.cpp:1532:0
#16 0x000000001510791c clang::CodeGen::CodeGenFunction::EmitDelegatingCXXConstructorCall(clang::CXXConstructorDecl const*, clang::CodeGen::FunctionArgList const&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGClass.cpp:2289:0
#17 0x000000001510efb8 clang::CodeGen::CodeGenFunction::EmitCtorPrologue(clang::CXXConstructorDecl const*, clang::CXXCtorType, clang::CodeGen::FunctionArgList&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGClass.cpp:1243:0
#18 0x000000001508242c clang::CodeGen::CodeGenFunction::EmitConstructorBody(clang::CodeGen::FunctionArgList&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGClass.cpp:839:0
#19 0x000000001507d230 clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenFunction.cpp:1218:0
#20 0x000000001507aef0 clang::CodeGen::CodeGenModule::codegenCXXStructor(clang::CXXMethodDecl const*, clang::CodeGen::StructorType) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CGCXX.cpp:234:0
#21 0x0000000014d88f18 (anonymous namespace)::ItaniumCXXABI::emitCXXStructor(clang::CXXMethodDecl const*, clang::CodeGen::StructorType) /llvm_trunk/llvm/tools/clang/lib/CodeGen/ItaniumCXXABI.cpp:3668:0
#22 0x000000001503bcf8 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenModule.cpp:2011:0
#23 0x0000000014f92b50 clang::CodeGen::CodeGenModule::EmitDeferred() /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenModule.cpp:1440:0
#24 0x0000000014daf498 clang::CodeGen::CodeGenModule::EmitDeferred() /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenModule.cpp:1447:0
#25 0x0000000014dabff8 clang::CodeGen::CodeGenModule::Release() /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenModule.cpp:385:0
#26 0x0000000014dac068 (anonymous namespace)::CodeGeneratorImpl::HandleTranslationUnit(clang::ASTContext&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/ModuleBuilder.cpp:265:0
#27 0x0000000014da5ea0 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenAction.cpp:204:0
#28 0x0000000015b478a0 clang::ParseAST(clang::Sema&, bool, bool) /llvm_trunk/llvm/tools/clang/lib/Parse/ParseAST.cpp:159:0
#29 0x0000000015b3bf14 clang::ASTFrontendAction::ExecuteAction() /llvm_trunk/llvm/tools/clang/lib/Frontend/FrontendAction.cpp:1004:0
#30 0x0000000016d027d8 clang::CodeGenAction::ExecuteAction() /llvm_trunk/llvm/tools/clang/lib/CodeGen/CodeGenAction.cpp:992:0
#31 0x0000000015482c6c clang::FrontendAction::Execute() /llvm_trunk/llvm/tools/clang/lib/Frontend/FrontendAction.cpp:902:0
#32 0x0000000015b3936c clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /llvm_trunk/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:986:0
#33 0x00000000154824d4 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /llvm_trunk/llvm/tools/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:252:0
#34 0x00000000153fb814 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /llvm_trunk/llvm/tools/clang/tools/driver/cc1_main.cpp:221:0
#35 0x0000000015657598 ExecuteCC1Tool(llvm::ArrayRef<char const*>, llvm::StringRef) /llvm_trunk/llvm/tools/clang/tools/driver/driver.cpp:302:0
#36 0x0000000011bd2e04 main /llvm_trunk/llvm/tools/clang/tools/driver/driver.cpp:381:0
#37 0x0000000011bc137c generic_start_main.isra.0 (/bin/clang+++0x11bc137c)
#38 0x0000000011bc1fb8 __libc_start_main (/bin/clang+++0x11bc1fb8)
/bin/clang++(_ZN4llvm3sys15PrintStackTraceERNS_11raw_ostreamE+0x58)[0x1481a998]
/bin/clang++[0x1481aa9c]
/bin/clang++(_ZN4llvm3sys17RunSignalHandlersEv+0xb4)[0x1481877c]
/bin/clang++[0x14819f40]
[0x3fff840e0478]
/lib64/libc.so.6(abort+0x280)[0x3fff83b30d70]
/lib64/libc.so.6(+0x348a4)[0x3fff83b248a4]
/lib64/libc.so.6(__assert_fail+0x64)[0x3fff83b24994]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction8EmitCallERKNS0_14CGFunctionInfoERKNS0_8CGCalleeENS0_15ReturnValueSlotERKNS0_11CallArgListEPPN4llvm11InstructionE+0x2738)[0x15057448]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction22EmitCXXConstructorCallEPKNS_18CXXConstructorDeclENS_11CXXCtorTypeEbbNS0_7AddressERNS0_11CallArgListE+0x5ac)[0x15080cd4]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction22EmitCXXConstructorCallEPKNS_18CXXConstructorDeclENS_11CXXCtorTypeEbbNS0_7AddressEPKNS_16CXXConstructExprE+0x2b4)[0x15080518]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction20EmitCXXConstructExprEPKNS_16CXXConstructExprENS0_12AggValueSlotE+0x454)[0x1511be9c]
/bin/clang++[0x1510c0a8]
/bin/clang++[0x151103d0]
/bin/clang++[0x1510791c]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction11EmitAggExprEPKNS_4ExprENS0_12AggValueSlotE+0x164)[0x1510efb8]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction32EmitDelegatingCXXConstructorCallEPKNS_18CXXConstructorDeclERKNS0_15FunctionArgListE+0xf4)[0x1508242c]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction16EmitCtorPrologueEPKNS_18CXXConstructorDeclENS_11CXXCtorTypeERNS0_15FunctionArgListE+0x58)[0x1507d230]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction19EmitConstructorBodyERNS0_15FunctionArgListE+0x294)[0x1507aef0]
/bin/clang++(_ZN5clang7CodeGen15CodeGenFunction12GenerateCodeENS_10GlobalDeclEPN4llvm8FunctionERKNS0_14CGFunctionInfoE+0x2d4)[0x14d88f18]
/bin/clang++(_ZN5clang7CodeGen13CodeGenModule18codegenCXXStructorEPKNS_13CXXMethodDeclENS0_12StructorTypeE+0x17c)[0x1503bcf8]
/bin/clang++[0x14f92b50]
/bin/clang++(_ZN5clang7CodeGen13CodeGenModule20EmitGlobalDefinitionENS_10GlobalDeclEPN4llvm11GlobalValueE+0x168)[0x14daf498]
/bin/clang++(_ZN5clang7CodeGen13CodeGenModule12EmitDeferredEv+0x1fc)[0x14dabff8]
/bin/clang++(_ZN5clang7CodeGen13CodeGenModule12EmitDeferredEv+0x26c)[0x14dac068]
/bin/clang++(_ZN5clang7CodeGen13CodeGenModule7ReleaseEv+0x30)[0x14da5ea0]
/bin/clang++[0x15b478a0]
/bin/clang++[0x15b3bf14]
/bin/clang++(_ZN5clang8ParseASTERNS_4SemaEbb+0x364)[0x16d027d8]
/bin/clang++(_ZN5clang17ASTFrontendAction13ExecuteActionEv+0x1d4)[0x15482c6c]
/bin/clang++(_ZN5clang13CodeGenAction13ExecuteActionEv+0x4a4)[0x15b3936c]
/bin/clang++(_ZN5clang14FrontendAction7ExecuteEv+0xbc)[0x154824d4]
/bin/clang++(_ZN5clang16CompilerInstance13ExecuteActionERNS_14FrontendActionE+0x5f0)[0x153fb814]
/bin/clang++(_ZN5clang25ExecuteCompilerInvocationEPNS_16CompilerInstanceE+0x7b8)[0x15657598]
/bin/clang++(_Z8cc1_mainN4llvm8ArrayRefIPKcEES2_Pv+0x4a8)[0x11bd2e04]
/bin/clang++[0x11bc137c]
/bin/clang++(main+0x9b8)[0x11bc1fb8]
/lib64/libc.so.6(+0x24700)[0x3fff83b14700]
/lib64/libc.so.6(__libc_start_main+0xc4)[0x3fff83b148f4]
Stack dump:
0.      Program arguments: /bin/clang++ -cc1 -xc++ -std=c++1z -emit-llvm -
1.      <eof> parser at end of file
2.      Per-file LLVM IR generation
3.      <stdin>:4:3: Generating code for declaration 'A::A'

COMPILER VERSION INFO (clang++ -v):

clang version 6.0.0 (trunk)
Target: powerpc64le-unknown-linux-gnu
Thread model: posix
InstalledDir: /bin
Found candidate GCC installation: /usr/lib/gcc/ppc64le-redhat-linux/4.8.2
Found candidate GCC installation: /usr/lib/gcc/ppc64le-redhat-linux/4.8.5
Selected GCC installation: /usr/lib/gcc/ppc64le-redhat-linux/4.8.5
Candidate multilib: .;@m64
Selected multilib: .;@m64
AaronBallman commented 2 years ago

This reproduces (with a slightly different assertion) with the same instructions as was originally provided using a build with assertions enabled:

Can confirm -- I had missed that the original was an assertion (despite it being in the title), so I was testing a release without asserts build. When I test on an asserts build, I get the miscompile. Thanks for reopening!

hubert-reinterpretcast commented 2 years ago

This reproduces (with a slightly different assertion) with the same instructions as was originally provided using a build with assertions enabled:

/llvm/clang/lib/CodeGen/CGCall.cpp:4669: clang::CodeGen::RValue clang::CodeGen::CodeGenFunction::EmitCall(const clang::CodeGen::CGFunctionInfo &, const clang::CodeGen::CGCallee &, clang::CodeGen::ReturnValueSlot, const clang::CodeGen::CallArgList &, llvm::CallBase **, bool, clang::SourceLocation): Assertion `IRFuncTy == TypeFromVal' failed.

The arguments to the inherited constructor are "passed into the void".

It seems that a different symptom of the same problem is how such arguments with non-trivial destruction fail to get destroyed when compiling for the MS ABI.

ONLINE COMPILER LINK:

https://godbolt.org/z/d4a5x8MYq

SOURCE:

struct NonTriv {
  NonTriv(int);
  ~NonTriv();
};
extern "C" void LookForThis(void);
NonTriv::~NonTriv() {
  LookForThis();
}
NonTriv LookForThat(void);
struct V { V() = default; V(NonTriv); };
struct A : virtual V {
  using V::V;
  A() : A(LookForThat()) { }
};
struct B : A { };
void foo() { B b; }

OPTIONS:

-target x86_64-pc-windows -emit-llvm -O -g0

IR output (snippet):

define dso_local void @"?foo@@YAXXZ"() local_unnamed_addr #2 personality i32 (...)* @__CxxFrameHandler3 {
  %1 = alloca %struct.NonTriv, align 1
  %2 = getelementptr inbounds %struct.NonTriv, %struct.NonTriv* %1, i64 0, i32 0
  call void @llvm.lifetime.start.p0i8(i64 1, i8* nonnull %2)
  call void @"?LookForThat@@YA?AUNonTriv@@XZ"(%struct.NonTriv* nonnull sret(%struct.NonTriv) align 1 %1)
  call void @llvm.lifetime.end.p0i8(i64 1, i8* nonnull %2)
  ret void
}

OBSERVATIONS:

It appears that there is no mechanism in the above by which the NonTriv temporary is destroyed.

Aside: I will open a GCC defect for its failure to process the side-effects of the argument initialization.

AaronBallman commented 2 years ago

I can no longer reproduce this issue with Clang trunk. If you're still seeing the problem with Clang trunk, please reopen this bug with additional details on how to reproduce.