<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/91536>91536</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
clang 18.1 parser crash
</td>
</tr>
<tr>
<th>Labels</th>
<td>
clang
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
drzdv
</td>
</tr>
</table>
<pre>
Godbolt link: https://godbolt.org/z/obG6EThzd
```cpp
decltype([]()->decltype(this){})
```
Produces following output:
> 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-18.1.0/bin/clang++ -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -S --gcc-toolchain=/opt/compiler-explorer/gcc-13.2.0 -fcolor-diagnostics -fno-crash-diagnostics -std=c++20 <source>
> 1. <source>:1:29: current parser token ')'
> 2. <source>:1:10: lambda expression parsing
> #0 0x000000000351ae38 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x351ae38)
> #1 0x0000000003518f84 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3518f84)
> #2 0x0000000003467018 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
> #3 0x00007bad21242520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
> #4 0x0000000006c0342c clang::FunctionDecl::hasCXXExplicitFunctionObjectParameter() const (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x6c0342c)
> #5 0x000000000623bb95 clang::Sema::ActOnCXXThis(clang::SourceLocation) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x623bb95)
> #6 0x0000000005c0f1f5 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, bool&, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c0f1f5)
> #7 0x0000000005c1197a clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c1197a)
> #8 0x0000000005c11b19 clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c11b19)
> #9 0x0000000005c16fa9 clang::Parser::ParseExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c16fa9)
> #10 0x0000000005bf311e clang::Parser::ParseDecltypeSpecifier(clang::DeclSpec&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bf311e)
> #11 0x0000000005c2be9b clang::Parser::ParseOptionalCXXScopeSpecifier(clang::CXXScopeSpec&, clang::OpaquePtr<clang::QualType>, bool, bool, bool*, bool, clang::IdentifierInfo**, bool, bool) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c2be9b)
> #12 0x0000000005b999bc clang::Parser::TryAnnotateCXXScopeToken(bool) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5b999bc)
> #13 0x0000000005bd8750 clang::Parser::ParseDeclarationSpecifiers(clang::DeclSpec&, clang::Parser::ParsedTemplateInfo const&, clang::AccessSpecifier, clang::Parser::DeclSpecContext, clang::Parser::LateParsedAttrList*, clang::ImplicitTypenameContext) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bd8750)
> #14 0x0000000005bd9a93 clang::Parser::ParseSpecifierQualifierList(clang::DeclSpec&, clang::ImplicitTypenameContext, clang::AccessSpecifier, clang::Parser::DeclSpecContext) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bd9a93)
> #15 0x0000000005bda13f clang::Parser::ParseTypeName(clang::SourceRange*, clang::DeclaratorContext, clang::AccessSpecifier, clang::Decl**, clang::ParsedAttributes*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bda13f)
> #16 0x0000000005c31f30 clang::Parser::ParseLambdaExpressionAfterIntroducer(clang::LambdaIntroducer&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c31f30)
> #17 0x0000000005c3281b clang::Parser::ParseLambdaExpression() (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c3281b)
> #18 0x0000000005c100e5 clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, bool&, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c100e5)
> #19 0x0000000005c1197a clang::Parser::ParseCastExpression(clang::Parser::CastParseKind, bool, clang::Parser::TypeCastState, bool, bool*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c1197a)
> #20 0x0000000005c11b19 clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c11b19)
> #21 0x0000000005c16fa9 clang::Parser::ParseExpression(clang::Parser::TypeCastState) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c16fa9)
> #22 0x0000000005bf311e clang::Parser::ParseDecltypeSpecifier(clang::DeclSpec&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bf311e)
> #23 0x0000000005c2be9b clang::Parser::ParseOptionalCXXScopeSpecifier(clang::CXXScopeSpec&, clang::OpaquePtr<clang::QualType>, bool, bool, bool*, bool, clang::IdentifierInfo**, bool, bool) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5c2be9b)
> #24 0x0000000005b999bc clang::Parser::TryAnnotateCXXScopeToken(bool) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5b999bc)
> #25 0x0000000005bd8750 clang::Parser::ParseDeclarationSpecifiers(clang::DeclSpec&, clang::Parser::ParsedTemplateInfo const&, clang::AccessSpecifier, clang::Parser::DeclSpecContext, clang::Parser::LateParsedAttrList*, clang::ImplicitTypenameContext) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5bd8750)
> #26 0x0000000005b9c10d clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5b9c10d)
> #27 0x0000000005b9d011 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5b9d011)
> #28 0x0000000005ba53af clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5ba53af)
> #29 0x0000000005ba6f27 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5ba6f27)
> #30 0x0000000005ba7540 clang::Parser::ParseFirstTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5ba7540)
> #31 0x0000000005b9638a clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x5b9638a)
> #32 0x0000000003d5a725 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3d5a725)
> #33 0x0000000003fe2aa1 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3fe2aa1)
> #34 0x0000000003f6010b clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3f6010b)
> #35 0x00000000040c2473 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x40c2473)
> #36 0x0000000000c19746 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0xc19746)
> #37 0x0000000000c1211d ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
> #38 0x0000000003da1979 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
> #39 0x0000000003467443 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3467443)
> #40 0x0000000003da1b99 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
> #41 0x0000000003d69d17 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3d69d17)
> #42 0x0000000003d6a6cd clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3d6a6cd)
> #43 0x0000000003d7445c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0x3d7445c)
> #44 0x0000000000c16a21 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0xc16a21)
> #45 0x0000000000b0fa84 main (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0xb0fa84)
> #46 0x00007bad21229d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
> #47 0x00007bad21229e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
> #48 0x0000000000c1191e _start (/opt/compiler-explorer/clang-18.1.0/bin/clang+++0xc1191e)
> clang++: error: clang frontend command failed with exit code 139 (use -v to see invocation)
> Compiler returned: 139
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWl2T2yjW_jXqG0ouAbI-LvpCcbfzZt7spjfdtZU7F0LIZiODFqGOe379FiC39WE7mVllprKZVBLLfD7nOYfDgwxpGr4VjN16yzfe8u6GtHon1W2hfi2eb3JZvNy-lUUuKw0qLj57OAM7revGw5mH1h5ab13tQqqth9a_emgt87fR_dPu18IL7rwg86LA_aV17UoKRiv9UjMPJW5S84BS38P3vSq9442HUi9-48V35mE4mvv6oGTRUtaAUlaV_MLFFshW1602-FwH9z--Bw_v77PHe9C0-Z5rQEDeboFitVQaaDm2iutdmy-o3HtoXVXPxw-_VvJfjGoPrXnTtKzx0BoQUQAuaNUWDOgdA1SRZgdyQj9rRSjz0ArUitVKUtY0rACNbJUrNj1J00jKiWYFUK0ADVW81osT7EdN6GdQtPv6ZBO-B8HCC9IHJbeK7AFR23bPhDYGAOOC2iCkcl_ziimfHepKKqZMWUXE1ofJAi4CD61zLo6FHnrjoTfA3xZfiCr9EPhb4EszGqlrM6blddEAf2-YAL5_SCKfNHu_eRGaHDx8x4VmFfAfge9vKfW1lBXdES48fHcVlGkM8QItAuCXVFZS-QUnWyEbzWkD_FJI35I6LG504eE76oCjAHh41VGL709EQUPUoApn0MMZSg1ZtFWKCQ1qohqmgJafmQAeik3Aofg0CrowCgzMKBXZ5wUB7FAr1jRcCjseF9vTAMBDOADBITj-wUtIGE6AjS6ceThrXhr38KC40NbvTy6AklMjRb5sZKMVI3sPRSaIuNAeSoFdRP-F5z30Jjh0oE7LrUMOR8iTMgnPIV9VjIi2_iAe-VaQykNJK2x-KUAlzUzz4TQQJjjRAGcYxQFMwMqEzkdG5TNTLw7Y_xFRVGa6pGNv0GYlhWYHvTAZC2eB_TeYBnfTxDkpEEQhWprws4ZVPPfQ-pBEmyj0Ky7ag78Vraugi0YuImuA7TKBH_bhRzTAIaLA2W7pXbeCai7FHaOVK9mRZvXp0_2hrjjl-lj_ITdJ6oEosmfammlspFI0eh7-O2wTA5YDAxDO83TZN-CR7Yl7yqj-IFafPj3ZNJ_029gl9l5SYkyZLWQ6NBPIUR_ykgYlLAeQH2xm6D2vSKPvX1f6EHu_sWlnv_8_F4VZqLmU1enTrt0LXZ9eajvNoyaaTbtms5HS2TshJR6SAmEak-9Lyp_PhDVywkQyZiKH6VUmMiuozG78LXyM7JvRmBymE2PSkTFRSa4b86eaYNANTDAb0WAPXeYlhpBdNeGuk5SPNaO85DYb9tqbalNlF-Rc2B2sCXY4pB_lLM2vYv9QmxRIqtWnT49UXrShXz1NLB9q8u-WPWjl4VWv-B8tqYzrjJaZrKve-jq7RN8VTGiL5J0opW2XTXvPFgqWqQmdaBgKaZrm9GIeUS-ZENKE6JGtJ6P1PJTMi9XBmGDFQ6xFEi-Dr4YtUXYLfPV6cyV0L2ZQ-1w8sX1dEc2Mu5wQmPbKqDmg9GLs4pjHmTuhdKXle6KZQ5Bprd5zM282Dqa9Uy8mGgXZs9dRZ_OJpXvik3Dkk5Sk-CqLr9SYtWMfnEHf5pSLZs7lhPnoMkxM6FqO6CIQl1fpMob-nezZOXn3kYgtm4bCMeql-j3sWFn8movG0GwE8rzV5tQ-o3BwTEzoGulKDEt8fcW_t4fI046bldqkV-1ecYxSvmvcr51x-3JgJxaNRCFGCby-fY0t6s4hc4E0809AjvVaELCfSc5beyekjHXfzynnPYRR8L8i540x8IeX8wj9uHIe4b_k_IxyHoU_jpxHYy30l5z_0-U8ikbxQ2FQfNUnH9TpnWr5Tmim3Gvrq-LxrH--2oKL7WUXT5w1XwAbHiZkxSOyigDCbw3gAWdccH1-P5mbsnGcfUfKDBsTyobKMidLTK6ff-4PLpx61P0xNM1GhLVxQkQ6IiIqUXz9ICjr9-yZVe58lnx9MzMN3yrZ1h9ZaTe0sdWn3xH-Jou2Yu_2tVRHyTLnzm-NGzOARy8hSbwMr6f_NVeN_pFpMBZOaICjJBLhZHqsyB6fRi8ADGhnyvfRFw7IBO3wt8FiSWI0OBmuZMHeMpHZzOaK7g-Mtpp1RTOeXrvpJxgHkhKXDBEySMtrZTZTUZwBOSs8N_MEXjiEFwUwyIcUugnfiUYTQdl5Fi_bM2PMdugmJgyUWxhQFMaDl34d2JMlz68_RCbXLJ0x73aoJtAHAiegMI3DCFAKN3tixuldEsiUIi82aazojqijQsy6w8GwDK3As-TFnBY4bBMD4pEBCMICHAlfwSebBXpmPO5JVf2TUS2VEZVnrbF55NTFjNEJzp4uTkGh-DNT53_RN9CSYXIgMI1TS0tv7LJTPRtlmbW1btW5-yAeziipqpzQz5tSDFO5m7-LnRVcyf2eiGK8gM960F5zMWWyOz56eNXjSCsutt0G4dz72mGzoYcDhO5LThpON41t3jE5aGwKNloRrptj9Wg4UlVmLUjVqzdNstELHMe77eKh2N2NsVdqjlSh5HgZ5BeZX_ZJOr7MEYa4545zVzZczcdWPJKSVS8DSq-7b7a843COYz8MxgGWp4N3NT9dgBi6FzVR2pB5PRLC4fWjIkoLGF8kz3qOTPbHI6ODND7qaBpcOk5faZoN5MysF206YyfhNBIzEYlo8VsZ-UXmzWU6fpG5Od8P6LiWml-joCbcBIC9WPXtDHah8h15NBRNeBwKriIOwyW9hPmu9zyQCWf0wSX-_0AeZ5OqlpQJc-FoM48I6qTqUY8ckdtEcnyl-PWteiYFYvBMQA_UX5AHJUlCYODOM6sbcDJrNLwuiNIi_Y3XBW2XybjxeFwWBmCzMV03jSZKb3qmffNMbHrSC5ORs2EKGXBzzOUvM-Rg3n4TnAGmlNlYMlcOyu7kAGi3AkrCK1aAL1zvADtwE1MFAxDbgGobBvxnoCVoGAO8J-p7Ex41PVBMt0owsw7NADfFLS5SnJIbdgtjuEQBCuLwZnebB5jGZRhCnCAcQEyKMIqXKVuWCWQowjf8FgUoDJZBgmAAYbiII5ZSCFkQQRoVy8ILA7YnvFqYZbGQantjr5XfpnCJo5uK5Kxq7M18hDo6kLe8u1G39jJ63m4bLwwq3ujmNILmumK3jiXD-vFus71BfdOq6vb333W3uP4TAAD__xDeWbY">