[Concepts] ICE on syntax error, in ConvertConstrainedAutoDeclSpecToType

[Quuxplusone]

Bugzilla Link	48593
Resolution	FIXED
Resolved on	Mar 12, 2021 16:30
Version	trunk
OS	All
CC	@mizvekov,@zygoloid

Extended Description

// https://godbolt.org/z/8Tb4aa
template concept C = true;
C<,> x

Originally reported by Leander Behr on the cpplang slack.

:3:3: error: expected expression C<,> x ^ :3:1: error: expected 'auto' or 'decltype(auto)' after concept name C<,> x ^ auto 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: /opt/compiler-explorer/clang-11.0.0/bin/clang++ -g -o ./output.s -mllvm --x86-asm-syntax=intel -S --gcc-toolchain=/opt/compiler-explorer/gcc-10.2.0 -fcolor-diagnostics -fno-crash-diagnostics -std=c++20 -O3 1. parser at end of file #​0 0x0000556f4e0b547a llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x2cab47a) #​1 0x0000556f4e0b3224 llvm::sys::RunSignalHandlers() (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x2ca9224) #​2 0x0000556f4e0b3495 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x2ca9495) #​3 0x0000556f4e027cc0 CrashRecoverySignalHandler(int) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x2c1dcc0) #​4 0x00007f672cfc23c0 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x153c0) #​5 0x0000556f50373f5b ConvertConstrainedAutoDeclSpecToType(clang::Sema&, clang::DeclSpec&, clang::AutoTypeKeyword) (.isra.674) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4f69f5b) #​6 0x0000556f50389932 GetDeclSpecTypeForDeclarator((anonymous namespace)::TypeProcessingState&, clang::TypeSourceInfo*&) (.constprop.1044) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4f7f932) #​7 0x0000556f50396e53 clang::Sema::GetTypeForDeclarator(clang::Declarator&, clang::Scope*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4f8ce53) #​8 0x0000556f4fe378ee clang::Sema::HandleDeclarator(clang::Scope*, clang::Declarator&, llvm::MutableArrayRef) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4a2d8ee) #​9 0x0000556f4fe38569 clang::Sema::ActOnDeclarator(clang::Scope*, clang::Declarator&) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4a2e569) #​10 0x0000556f4fc07d70 clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47fdd70) #​11 0x0000556f4fc0e705 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x4804705) #​12 0x0000556f4fbf0df9 clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47e6df9) #​13 0x0000556f4fbf1af1 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (.part.228) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47e7af1) #​14 0x0000556f4fbf79c9 clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47ed9c9) #​15 0x0000556f4fbf90d9 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr&, bool) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47ef0d9) #​16 0x0000556f4fbecd19 clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x47e2d19) #​17 0x0000556f4e8a1479 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x3497479) #​18 0x0000556f4e85af9b clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x3450f9b) #​19 0x0000556f4e967b2b clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x355db2b) #​20 0x0000556f4c29014c cc1_main(llvm::ArrayRef, char const*, void*) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0xe8614c) #​21 0x0000556f4c28cc4d ExecuteCC1Tool(llvm::SmallVectorImpl&) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0xe82c4d) #​22 0x0000556f4e732c45 void llvm::function_ref::callback_fn >, std::__cxx11::basic_string, std::allocator >*, bool*) const::'lambda'()>(long) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x3328c45) #​23 0x0000556f4e027da3 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x2c1dda3) #​24 0x0000556f4e733720 clang::driver::CC1Command::Execute(llvm::ArrayRef >, std::__cxx11::basic_string, std::allocator >*, bool*) const (.part.148) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x3329720) #​25 0x0000556f4e70d8f5 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&) const (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x33038f5) #​26 0x0000556f4e70e33f clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl >&) const (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x330433f) #​27 0x0000556f4e716ed5 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl >&) (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0x330ced5) #​28 0x0000556f4c1ccdc1 main (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0xdc2dc1) #​29 0x00007f672ca730b3 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b3) #​30 0x0000556f4c28c7ca _start (/opt/compiler-explorer/clang-11.0.0/bin/clang+++0xe827ca)

[Quuxplusone]

assigned to @mizvekov

[mizvekov]

Might be the same bug, slightly different stack trace:

clang++-11 -std=c++20 -fsyntax-only -fno-crash-diagnostics test.cc

template <class T, class U> concept b = requires { true; };
b<c> auto d = 0;

===>

test.cc:2:3: error: use of undeclared identifier 'c'
b<c> auto d = 0;
  ^
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: clang++-11 -std=c++20 -fsyntax-only -fno-crash-diagnostics test.cc
1.      test.cc:2:13: current parser token '='
 #&#8203;0 0x00007f733b140f8f llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/usr/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbd0f8f)
 #&#8203;1 0x00007f733b13f2f0 llvm::sys::RunSignalHandlers() (/usr/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbcf2f0)
 #&#8203;2 0x00007f733b1406dd llvm::sys::CleanupOnSignal(unsigned long) (/usr/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbd06dd)
 #&#8203;3 0x00007f733b084dc0 (/usr/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb14dc0)
 #&#8203;4 0x00007f7342329140 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14140)
 #&#8203;5 0x00007f7340cb22c6 (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x16422c6)
 #&#8203;6 0x00007f7340c9db6b (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x162db6b)
 #&#8203;7 0x00007f7340c9cf48 clang::Sema::GetTypeForDeclarator(clang::Declarator&, clang::Scope*) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x162cf48)
 #&#8203;8 0x00007f7340772117 clang::Sema::HandleDeclarator(clang::Scope*, clang::Declarator&, llvm::MutableArrayRef<clang::TemplateParameterList*>) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1102117)
 #&#8203;9 0x00007f7340771888 clang::Sema::ActOnDeclarator(clang::Scope*, clang::Declarator&) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1101888)
#&#8203;10 0x00007f734005b680 clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x9eb680)
#&#8203;11 0x00007f734005a2c9 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x9ea2c9)
#&#8203;12 0x00007f73400e7aad clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0xa77aad)
#&#8203;13 0x00007f73400e74bc clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0xa774bc)
#&#8203;14 0x00007f73400e6746 clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0xa76746)
#&#8203;15 0x00007f73400e4c9b clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, bool) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0xa74c9b)
#&#8203;16 0x00007f73400476ed clang::ParseAST(clang::Sema&, bool, bool) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x9d76ed)
#&#8203;17 0x00007f73416130c8 clang::FrontendAction::Execute() (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1fa30c8)
#&#8203;18 0x00007f73415c9641 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1f59641)
#&#8203;19 0x00007f7341679200 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x2009200)
#&#8203;20 0x00000000004131bf cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/usr/lib/llvm-11/bin/clang+0x4131bf)
#&#8203;21 0x00000000004115fe (/usr/lib/llvm-11/bin/clang+0x4115fe)
#&#8203;22 0x00007f73412fc732 (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c8c732)
#&#8203;23 0x00007f733b084bcd llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/usr/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb14bcd)
#&#8203;24 0x00007f73412fbc5f clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c8bc5f)
#&#8203;25 0x00007f73412d3a7f clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&) const (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c63a7f)
#&#8203;26 0x00007f73412d3c27 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) const (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c63c27)
#&#8203;27 0x00007f73412e778c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) (/usr/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c7778c)
#&#8203;28 0x00000000004110a3 main (/usr/lib/llvm-11/bin/clang+0x4110a3)
#&#8203;29 0x00007f733a086d0a __libc_start_main ./csu/../csu/libc-start.c:308:16
#&#8203;30 0x000000000040e89a _start (/usr/lib/llvm-11/bin/clang+0x40e89a)
clang: error: clang frontend command failed due to signal (use -v to see invocation)

[mizvekov]

*** Bug llvm/llvm-bugzilla-archive#48601 has been marked as a duplicate of this bug. ***

[mizvekov]

This is fixed by https://reviews.llvm.org/D98095

[mizvekov]

Patch has landed: d4a8c73

[mizvekov]

mentioned in issue llvm/llvm-bugzilla-archive#48601