ICE on valid code: UNREACHABLE executed at llvm-project/clang/lib/CodeGen/CGExpr.cpp, __attribute__((naked))

[chengniansun]

Bugzilla Link	51197
Version	trunk
OS	All
CC	@zygoloid

Extended Description

$ clang-trunk -v
clang version 13.0.0 (https://github.com/llvm/llvm-project.git ab5ac65)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/cnsun/usr/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/10
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/9
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/10
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@MX32
Selected multilib: .;@m64

$ cat mutant.c
attribute((naked)) foo(int len, char[len]) {}

$ clang-trunk mutant.c
mutant.c:1:24: warning: type specifier missing, defaults to 'int' [-Wimplicit-int]
attribute((naked)) foo(int len, char[len]) {}
^
mutant.c:1:41: warning: omitting the parameter name in a function definition is a C2x extension [-Wc2x-extensions]
attribute((naked)) foo(int len, char[len]) {}
^
DeclRefExpr for Decl not entered in LocalDeclMap?
UNREACHABLE executed at /tmp/tmp.Gcp8nSn9Hr-clang-builder/llvm-project/clang/lib/CodeGen/CGExpr.cpp:2794!
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: /scratch/software/clang-trunk/bin/clang-13 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -mrelax-all --mrelax-relocations -disable-free -main-file-name mutant.c -mrelocation-model static -mframe-pointer=all -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/scratch/cnsun/workspace/perses-fuzzer/temp_testing_campaigns/default_finding_folder_c/crash_20210707_101723_1c32/delta/perses_result -resource-dir /scratch/software/clang-trunk/lib/clang/13.0.0 -c-isystem . -c-isystem /usr/local/include/cmsith -internal-isystem /scratch/software/clang-trunk/lib/clang/13.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdebug-compilation-dir=/scratch/cnsun/workspace/perses-fuzzer/temp_testing_campaigns/default_finding_folder_c/crash_20210707_101723_1c32/delta/perses_result -ferror-limit 19 -fgnuc-version=4.2.1 -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/mutant-8f3361.o -x c mutant.c

1. parser at end of file
2. mutant.c:1:24: LLVM IR generation of declaration 'foo'
3. mutant.c:1:24: Generating code for declaration 'foo'
   #​0 0x000055bbe2b60754 PrintStackTraceSignalHandler(void*) Signals.cpp:0:0
   #​1 0x000055bbe2b5de6e SignalHandler(int) Signals.cpp:0:0
   #​2 0x00007fd9c1a1d3c0 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x153c0)
   #​3 0x00007fd9c14bc18b raise /build/glibc-ZN95T4/glibc-2.31/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
   #​4 0x00007fd9c149b859 abort /build/glibc-ZN95T4/glibc-2.31/stdlib/abort.c:81:7
   #​5 0x000055bbe2aaa94e (/scratch/software/clang-trunk/bin/clang-13+0x3a6f94e)
   #​6 0x000055bbe3228da8 clang::CodeGen::CodeGenFunction::EmitDeclRefLValue(clang::DeclRefExpr const*) (/scratch/software/clang-trunk/bin/clang-13+0x41edda8)
   #​7 0x000055bbe3223ee9 clang::CodeGen::CodeGenFunction::EmitLValue(clang::Expr const*) (/scratch/software/clang-trunk/bin/clang-13+0x41e8ee9)
   #​8 0x000055bbe322e5fc clang::CodeGen::CodeGenFunction::EmitCheckedLValue(clang::Expr const*, clang::CodeGen::CodeGenFunction::TypeCheckKind) (/scratch/software/clang-trunk/bin/clang-13+0x41f35fc)
   #​9 0x000055bbe3269e21 (anonymous namespace)::ScalarExprEmitter::EmitLoadOfLValue(clang::Expr const*) CGExprScalar.cpp:0:0
   #​10 0x000055bbe3269454 (anonymous namespace)::ScalarExprEmitter::Visit(clang::Expr*) CGExprScalar.cpp:0:0
   #​11 0x000055bbe326fd53 (anonymous namespace)::ScalarExprEmitter::VisitCastExpr(clang::CastExpr*) CGExprScalar.cpp:0:0
   #​12 0x000055bbe32677ce (anonymous namespace)::ScalarExprEmitter::Visit(clang::Expr*) CGExprScalar.cpp:0:0
   #​13 0x000055bbe326982a clang::CodeGen::CodeGenFunction::EmitScalarExpr(clang::Expr const*, bool) (/scratch/software/clang-trunk/bin/clang-13+0x422e82a)
   #​14 0x000055bbe2f63eec clang::CodeGen::CodeGenFunction::EmitVariablyModifiedType(clang::QualType) (/scratch/software/clang-trunk/bin/clang-13+0x3f28eec)
   #​15 0x000055bbe2f660ec clang::CodeGen::CodeGenFunction::StartFunction(clang::GlobalDecl, clang::QualType, llvm::Function*, clang::CodeGen::CGFunctionInfo const&, clang::CodeGen::FunctionArgList const&, clang::SourceLocation, clang::SourceLocation) (/scratch/software/clang-trunk/bin/clang-13+0x3f2b0ec)
   #​16 0x000055bbe2f6ae3f clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) (/scratch/software/clang-trunk/bin/clang-13+0x3f2fe3f)
   #​17 0x000055bbe2fc54c6 clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/scratch/software/clang-trunk/bin/clang-13+0x3f8a4c6)
   #​18 0x000055bbe2fc0f35 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/scratch/software/clang-trunk/bin/clang-13+0x3f85f35)
   #​19 0x000055bbe2fc139b clang::CodeGen::CodeGenModule::EmitGlobal(clang::GlobalDecl) (/scratch/software/clang-trunk/bin/clang-13+0x3f8639b)
   #​20 0x000055bbe2fc9eb2 clang::CodeGen::CodeGenModule::EmitTopLevelDecl(clang::Decl*) (.part.0) CodeGenModule.cpp:0:0
   #​21 0x000055bbe3cf6179 (anonymous namespace)::CodeGeneratorImpl::HandleTopLevelDecl(clang::DeclGroupRef) ModuleBuilder.cpp:0:0
   #​22 0x000055bbe3ce8380 clang::BackendConsumer::HandleTopLevelDecl(clang::DeclGroupRef) (/scratch/software/clang-trunk/bin/clang-13+0x4cad380)
   #​23 0x000055bbe4db8d34 clang::ParseAST(clang::Sema&, bool, bool) (/scratch/software/clang-trunk/bin/clang-13+0x5d7dd34)
   #​24 0x000055bbe3cf32f8 clang::CodeGenAction::ExecuteAction() (/scratch/software/clang-trunk/bin/clang-13+0x4cb82f8)
   #​25 0x000055bbe3591419 clang::FrontendAction::Execute() (/scratch/software/clang-trunk/bin/clang-13+0x4556419)
   #​26 0x000055bbe352707e clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/scratch/software/clang-trunk/bin/clang-13+0x44ec07e)
   #​27 0x000055bbe366f710 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/scratch/software/clang-trunk/bin/clang-13+0x4634710)
   #​28 0x000055bbe03db15d cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/scratch/software/clang-trunk/bin/clang-13+0x13a015d)
   #​29 0x000055bbe03d74a8 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0
   #​30 0x000055bbe0302126 main (/scratch/software/clang-trunk/bin/clang-13+0x12c7126)
   #​31 0x00007fd9c149d0b3 __libc_start_main /build/glibc-ZN95T4/glibc-2.31/csu/../csu/libc-start.c:342:3
   #​32 0x000055bbe03d701e _start (/scratch/software/clang-trunk/bin/clang-13+0x139c01e)
   clang-13: error: unable to execute command: Aborted (core dumped)
   clang-13: error: clang frontend command failed due to signal (use -v to see invocation)
   clang version 13.0.0 (https://github.com/llvm/llvm-project.git ab5ac65)
   Target: x86_64-unknown-linux-gnu
   Thread model: posix
   InstalledDir: /home/cnsun/usr/bin
   clang-13: note: diagnostic msg:

---

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-13: note: diagnostic msg: /tmp/mutant-c1dca7.c
clang-13: note: diagnostic msg: /tmp/mutant-c1dca7.sh
clang-13: note: diagnostic msg:

---

[AaronBallman]

Note, this requires an assertions build to trigger the ICE.

https://reviews.llvm.org/D122341 should improve the situation.

[llvmbot]

@llvm/issue-subscribers-clang-codegen

[AaronBallman]

This should now be fixed in 488c772.