llvmbot
commented
3 hours ago @llvm/issue-subscribers-clang-frontend
Author: Yihan Yang (yijan4845)
**This testcase is generated by a fuzzer.**
Compiler explorer: [https://godbolt.org/z/aehhzKdd1](https://godbolt.org/z/aehhzKdd1)
This invalid code will crash on both Clang Trunk and Clang Assertion Trunk:
```cpp
template<typename = int>
struct ct {
friend void f(ct, int = 0);
};
void test() {
f(ct<>{});
}
```
It seems that this goes back to clang-11.
Stack dump:
```
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. <source>:6:11: current parser token ')'
2. <source>:5:13: parsing function body 'test'
3. <source>:5:13: in compound statement ('{}')
#0 0x0000000003bc6148 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3bc6148)
#1 0x0000000003bc3e0c llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3bc3e0c)
#2 0x0000000003b114b8 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
#3 0x0000786adf842520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
#4 0x0000000007a69a14 clang::FunctionDecl::getNumParams() const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x7a69a14)
#5 0x0000000007463bc7 clang::Sema::addInstantiatedParametersToScope(clang::FunctionDecl*, clang::FunctionDecl const*, clang::LocalInstantiationScope&, clang::MultiLevelTemplateArgumentList const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x7463bc7)
#6 0x00000000073bdeb5 clang::Sema::SubstDefaultArgument(clang::SourceLocation, clang::ParmVarDecl*, clang::MultiLevelTemplateArgumentList const&, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x73bdeb5)
#7 0x0000000007463fb4 clang::Sema::InstantiateDefaultArgument(clang::SourceLocation, clang::FunctionDecl*, clang::ParmVarDecl*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x7463fb4)
#8 0x0000000006c71c8d clang::Sema::BuildCXXDefaultArgExpr(clang::SourceLocation, clang::FunctionDecl*, clang::ParmVarDecl*, clang::Expr*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6c71c8d)
#9 0x0000000006c9c7d6 clang::Sema::GatherArgumentsForCall(clang::SourceLocation, clang::FunctionDecl*, clang::FunctionProtoType const*, unsigned int, llvm::ArrayRef<clang::Expr*>, llvm::SmallVectorImpl<clang::Expr*>&, clang::Sema::VariadicCallType, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6c9c7d6)
#10 0x0000000006c9dba7 clang::Sema::ConvertArgumentsForCall(clang::CallExpr*, clang::Expr*, clang::FunctionDecl*, clang::FunctionProtoType const*, llvm::ArrayRef<clang::Expr*>, clang::SourceLocation, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6c9dba7)
#11 0x0000000006c9f791 clang::Sema::BuildResolvedCallExpr(clang::Expr*, clang::NamedDecl*, clang::SourceLocation, llvm::ArrayRef<clang::Expr*>, clang::SourceLocation, clang::Expr*, bool, clang::CallExpr::ADLCallKind) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6c9f791)
#12 0x000000000712ee9a FinishOverloadedCallExpr(clang::Sema&, clang::Scope*, clang::Expr*, clang::UnresolvedLookupExpr*, clang::SourceLocation, llvm::MutableArrayRef<clang::Expr*>, clang::SourceLocation, clang::Expr*, clang::OverloadCandidateSet*, clang::OverloadCandidate**, clang::OverloadingResult, bool) SemaOverload.cpp:0:0
#13 0x000000000712fda4 clang::Sema::BuildOverloadedCallExpr(clang::Scope*, clang::Expr*, clang::UnresolvedLookupExpr*, clang::SourceLocation, llvm::MutableArrayRef<clang::Expr*>, clang::SourceLocation, clang::Expr*, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x712fda4)
#14 0x0000000006ca13b8 clang::Sema::BuildCallExpr(clang::Scope*, clang::Expr*, clang::SourceLocation, llvm::MutableArrayRef<clang::Expr*>, clang::SourceLocation, clang::Expr*, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6ca13b8)
#15 0x0000000006ca391c clang::Sema::ActOnCallExpr(clang::Scope*, clang::Expr*, clang::SourceLocation, llvm::MutableArrayRef<clang::Expr*>, clang::SourceLocation, clang::Expr*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6ca391c)
#16 0x0000000006709a0d clang::Parser::ParsePostfixExpressionSuffix(clang::ActionResult<clang::Expr*, true>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6709a0d)
#17 0x00000000067023d1 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, bool&, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x67023d1)
#18 0x0000000006704527 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6704527)
#19 0x00000000067045b9 clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x67045b9)
#20 0x0000000006708fd9 clang::Parser::ParseExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6708fd9)
#21 0x000000000678bde9 clang::Parser::ParseExprStatement(clang::Parser::ParsedStmtContext) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x678bde9)
#22 0x000000000678215c clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x678215c)
#23 0x0000000006783070 clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6783070)
#24 0x0000000006783f45 clang::Parser::ParseCompoundStatementBody(bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6783f45)
#25 0x000000000678569a clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x678569a)
#26 0x0000000006699223 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6699223)
#27 0x00000000066cd8dd clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x66cd8dd)
#28 0x000000000668cf6e clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x668cf6e)
#29 0x000000000668d72e clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x668d72e)
#30 0x0000000006694ec3 clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6694ec3)
#31 0x0000000006695dad clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6695dad)
#32 0x00000000066882ca clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x66882ca)
#33 0x000000000453b728 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x453b728)
#34 0x00000000047f6bf9 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x47f6bf9)
#35 0x00000000047756be clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x47756be)
#36 0x00000000048dc3de clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x48dc3de)
#37 0x0000000000cdee3f cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xcdee3f)
#38 0x0000000000cd6b3a ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#39 0x000000000457f449 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
#40 0x0000000003b11964 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3b11964)
#41 0x000000000457fa3f 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
#42 0x000000000454533d clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x454533d)
#43 0x000000000454642d 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+++0x454642d)
#44 0x000000000454dd55 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x454dd55)
#45 0x0000000000cdbcff clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xcdbcff)
#46 0x0000000000baadf4 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xbaadf4)
#47 0x0000786adf829d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#48 0x0000786adf829e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#49 0x0000000000cd65ee _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xcd65ee)
clang++: error: clang frontend command failed with exit code 139 (use -v to see invocation)
Compiler returned: 139
```
This testcase is generated by a fuzzer.
Compiler explorer: https://godbolt.org/z/aehhzKdd1
This invalid code will crash on both Clang Trunk and Clang Assertion Trunk:
It seems that this goes back to clang-11.
Stack dump: