llvmbot
commented
1 month ago @llvm/issue-subscribers-clang-codegen
Author: Yihan Yang (yijan4845)
**This testcase is generated by a fuzzer.**
Compiler Explorer: [https://godbolt.org/z/qTe9ajeK7](https://godbolt.org/z/qTe9ajeK7)
This valid code will crash on Clang Trunk and Clang Assertion Trunk.
```cpp
template <typename T_1> int foo();
int __attribute__((target("default"))) foo(void) { return 2; }
int bar() {
return foo();
}
```
It seems that this goes back to clang-7.
Stack dump:
```
unexpected MultiVersionKind
UNREACHABLE executed at /root/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:4327!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/clang++ -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -fno-verbose-asm -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics <source>
1. <eof> parser at end of file
2. Per-file LLVM IR generation
#0 0x0000000003bcced8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3bcced8)
#1 0x0000000003bcab9c llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3bcab9c)
#2 0x0000000003b18248 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
#3 0x00007ab480242520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
#4 0x00007ab4802969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
#5 0x00007ab480242476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
#6 0x00007ab4802287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
#7 0x0000000003b23b1a (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3b23b1a)
#8 0x000000000401bdac clang::CodeGen::CodeGenModule::emitMultiVersionFunctions()::'lambda0'(clang::FunctionDecl const*)::operator()(clang::FunctionDecl const*) const CodeGenModule.cpp:0:0
#9 0x00000000078e8f71 clang::ASTContext::forEachMultiversionedFunctionVersion(clang::FunctionDecl const*, llvm::function_ref<void (clang::FunctionDecl*)>) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x78e8f71)
#10 0x0000000004021e32 clang::CodeGen::CodeGenModule::emitMultiVersionFunctions() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4021e32)
#11 0x0000000004023f18 clang::CodeGen::CodeGenModule::Release() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4023f18)
#12 0x000000000454483e (anonymous namespace)::CodeGeneratorImpl::HandleTranslationUnit(clang::ASTContext&) ModuleBuilder.cpp:0:0
#13 0x0000000004542495 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4542495)
#14 0x000000000669945c clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x669945c)
#15 0x0000000004542c48 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4542c48)
#16 0x00000000047fe239 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x47fe239)
#17 0x000000000477cbde clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x477cbde)
#18 0x00000000048e3a0e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x48e3a0e)
#19 0x0000000000ce1c8f cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xce1c8f)
#20 0x0000000000cd998a ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#21 0x0000000004586969 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::'lambda'()>(long) Job.cpp:0:0
#22 0x0000000003b186f4 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3b186f4)
#23 0x0000000004586f5f clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (.part.0) Job.cpp:0:0
#24 0x000000000454c85d clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x454c85d)
#25 0x000000000454d94d clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x454d94d)
#26 0x0000000004555275 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4555275)
#27 0x0000000000cdeb4f clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xcdeb4f)
#28 0x0000000000badae4 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xbadae4)
#29 0x00007ab480229d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#30 0x00007ab480229e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#31 0x0000000000cd943e _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xcd943e)
clang++: error: clang frontend command failed with exit code 134 (use -v to see invocation)
ASM generation compiler returned: 134
```
This testcase is generated by a fuzzer.
Compiler Explorer: https://godbolt.org/z/qTe9ajeK7
This valid code will crash on Clang Trunk and Clang Assertion Trunk.
It seems that this goes back to clang-7.
Stack dump: