<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/151716>151716</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Assertion `CAT && "vla in literal type?"' failed.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c++20,
            clang:frontend,
            crash
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          k-arrows
      </td>
    </tr>
</table>

<pre>
    Reproducer:
https://godbolt.org/z/89EbxxGfT
```cpp
constexpr int f() {
  int(&&g)[]{0};
  return g[0];
}
```

Backtrace:
```console
clang++: /root/llvm-project/llvm/tools/clang/lib/AST/ExprConstant.cpp:4032: typename SubobjectHandler::result_type findSubobject({anonymous}::EvalInfo&, const clang::Expr*, const {anonymous}::CompleteObject&, const {anonymous}::SubobjectDesignator&, SubobjectHandler&) [with SubobjectHandler = {anonymous}::ExtractSubobjectHandler; typename SubobjectHandler::result_type = bool]: Assertion `CAT && "vla in literal type?"' failed.
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 --std=c++20 <source>
1.      <eof> parser at end of file
2.      <source>:1:19: parsing function body 'f'
 #0 0x0000000003fdb0d8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3fdb0d8)
 #1 0x0000000003fd8504 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3fd8504)
 #2 0x0000000003f1ccf8 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x0000763a86042520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x0000763a860969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #5 0x0000763a86042476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #6 0x0000763a860287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #7 0x0000763a8602871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #8 0x0000763a86039e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #9 0x00000000078c66bf (anonymous namespace)::ExtractSubobjectHandler::result_type findSubobject<(anonymous namespace)::ExtractSubobjectHandler>((anonymous namespace)::EvalInfo&, clang::Expr const*, (anonymous namespace)::CompleteObject const&, (anonymous namespace)::SubobjectDesignator const&, (anonymous namespace)::ExtractSubobjectHandler&) ExprConstant.cpp:0:0
#10 0x00000000078c7198 handleLValueToRValueConversion((anonymous namespace)::EvalInfo&, clang::Expr const*, clang::QualType, (anonymous namespace)::LValue const&, clang::APValue&, bool) ExprConstant.cpp:0:0
#11 0x000000000791b91f (anonymous namespace)::IntExprEvaluator::VisitCastExpr(clang::CastExpr const*) ExprConstant.cpp:0:0
#12 0x00000000078dd09b clang::StmtVisitorBase<llvm::make_const_ptr, (anonymous namespace)::IntExprEvaluator, bool>::Visit(clang::Stmt const*) ExprConstant.cpp:0:0
#13 0x00000000078ce2b6 Evaluate(clang::APValue&, (anonymous namespace)::EvalInfo&, clang::Expr const*) ExprConstant.cpp:0:0
#14 0x00000000078ef8db EvaluateStmt((anonymous namespace)::StmtResult&, (anonymous namespace)::EvalInfo&, clang::Stmt const*, clang::SwitchCase const*) (.part.0) ExprConstant.cpp:0:0
#15 0x00000000078ee7e8 EvaluateStmt((anonymous namespace)::StmtResult&, (anonymous namespace)::EvalInfo&, clang::Stmt const*, clang::SwitchCase const*) (.part.0) ExprConstant.cpp:0:0
#16 0x00000000078f516b HandleFunctionCall(clang::SourceLocation, clang::FunctionDecl const*, (anonymous namespace)::LValue const*, clang::Expr const*, llvm::ArrayRef<clang::Expr const*>, (anonymous namespace)::CallRef, clang::Stmt const*, (anonymous namespace)::EvalInfo&, clang::APValue&, (anonymous namespace)::LValue const*) ExprConstant.cpp:0:0
#17 0x000000000793ef04 clang::Expr::isPotentialConstantExpr(clang::FunctionDecl const*, llvm::SmallVectorImpl<std::pair<clang::SourceLocation, clang::PartialDiagnostic>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x793ef04)
#18 0x0000000006ad2756 clang::Sema::CheckConstexprFunctionDefinition(clang::FunctionDecl const*, clang::Sema::CheckConstexprKind) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6ad2756)
#19 0x0000000006a5b003 clang::Sema::ActOnFinishFunctionBody(clang::Decl*, clang::Stmt*, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6a5b003)
#20 0x00000000067a098f clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x67a098f)
#21 0x0000000006698063 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6698063)
#22 0x00000000066cde4d 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+++0x66cde4d)
#23 0x000000000668ae3e clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x668ae3e)
#24 0x000000000668b5cf clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x668b5cf)
#25 0x00000000066932da clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x66932da)
#26 0x0000000006694265 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6694265)
#27 0x0000000006694720 clang::Parser::ParseFirstTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6694720)
#28 0x0000000006685fa3 clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6685fa3)
#29 0x0000000004987388 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4987388)
#30 0x0000000004c7aa05 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4c7aa05)
#31 0x0000000004bf780e clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4bf780e)
#32 0x0000000004d6e731 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4d6e731)
#33 0x0000000000daa41f cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xdaa41f)
#34 0x0000000000da106a ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#35 0x00000000049eeaa9 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
#36 0x0000000003f1d194 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3f1d194)
#37 0x00000000049ef0bf 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
#38 0x00000000049b16ed clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x49b16ed)
#39 0x00000000049b277e 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+++0x49b277e)
#40 0x00000000049ba7b5 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x49ba7b5)
#41 0x0000000000da68cf clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xda68cf)
#42 0x0000000000c5b7d4 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xc5b7d4)
#43 0x0000763a86029d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#44 0x0000763a86029e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#45 0x0000000000da0b15 _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0xda0b15)
clang++: error: clang frontend command failed with exit code 134 (use -v to see invocation)
Compiler returned: 134
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzkWk1z6yjW_jVkQzkloe9FFooT95t-M3UzSaq3LiQhmwkGDaBcZ379FEiyPuzYcXd8Fz23krqKgMPzPBwORwBWiq44ITcguAXB3RWu9VrIm7cZllL8VFeZKD5unkklRVHnRAIvBU661rpS5hEtAFqsRJEJpq-FXAG0-A9Aizi5z7bb38pX4KQgdJqfvKqAk-aCK022lYSUa1gCFAOUQBDdAieF5p19EwIUrgBKGlAgunVAdAe8ppIkupYcrkBw65hS-9qUDzozz056i_M3LXFOGtg9FMGVYMTAYZivALo1P14KAVpIITRAC8beN7NKin-RvPsToIUWgimAFm2zBaMZQIv05RWgxf22knPDDnN9bch6qe94yJjVHxXheEPgS52JzJj8P8wL1sjppZKomumlqQVLyotdLaNFdIu54B8bUSurgWlw_47ZAy-FFWoOraawwdSUbysJUNqXHbQyF5uKEU1-tH2FJ-rvYN0R4zNYC9k22qNlXicQBLc_qV7vFUPg3R3u4n5rhkvvy3R7jobGfCYEs86RwlQpIjUVHILQmaevsPEvCBB6ZxhSDhnVRGJm-wDeAiAEUARLTBkproGTPj3epy_3UNXZhmqIYVavoCSVkBpqASezgep1nV3nYtO7zcSZqFI1MW4EMS8g5TmrCwL1msBcYrWG2c5t0RxW0ky-nChFCqhELZvXpiVWSuQUa1JAWXOockkrbfC-aJy_waLeVI3jO9fASZ6kWEm8gViu6g3hWrUOLyqDKRebijIiZ2RbMSHNGDZePsOdfGqmZc3fAFpklPeTwMwdOFsVP7EsZz6creBMGLu4qoz1Wle1vlZwtjEqwNlsG4czrDYz9cE13gLvjnJNGJyVXMzeicyEIqYczl7gbLbK85mZdPkaUw68u6N4TWXFcaXWQsNZmQsm5KygeMWF0jRXTR9W4_HrmdIF8O7yhgxyIPDmrdTePXBS1-gHvDkRJfDuYYWlIhJiDQkvoChhSW0wQW21vqmXuuY3MVKbVpSvYFnz3HqjCa0QoKgEKDKBDSDPgc7W6f55ZZE5RQytE1knVx-qeXiSlGs7yq-Nn8R9JYl_LoXSkuBNOz1tVE2gjazfMtwA3TrbFp6J0g14dwI-Dhz_EPg5I5jX1Q_-YqIIAyiuuV2ECsiE6eISUA2YHioaQ3XzvIzh3DjGM8nFO5EfDbZdPItbDUd15oJrsu2CvWN_G_teaz8KPRyHjo8C41SWVLNkbONwGfozRnm9na143RTk10pchxaybdID9scGkzApc1jptSS4WL5Rxs6zbtv31oMpXD8K4coG-TMN26a94XBsGMVR6UGcmcB5llnbsDcb7Zl1s7MNullvMB4b9BKShOcZtE16g8nQwaI4D8OsNAZ3Sx40a5mq7ORNTix-x3MEb_5n7d5bhsfbTjKNcY7RZAttpnHC0jjb6FqGX2h5IO84p_ln9Jsc5UDW1k1kE9KcyThGbhLDtbXw-AdmNXkVz_b_ueDvRCoq-LeKOij7Z43Zq0lQTlNuoI1EGhhKn2xxW2ATpdNCjIJ7lLhZ4p506AeujVVDt7bZon37B1VUz7HSTZYaD5B1bwcSnASGxiNUFE6SDdm-6I22XQp5ixUB3rxfkjb4jSxtX8tKyy8Iu8eoE9Cu9R25MSkD4BxC3sTlCMpC2PZIxqbHI_ldXncSoT9GSMq4yHYIDd3TU8DUerYh7a-Cn8g7LvtJdb6eY0VG9ACKryss9bXzBbLBhCyJSPy3JRuOyZaBG2awCZiLNm2dY8YmDm7T3UeRY23D3whV1-yO5Oyc5WIcwqZc9-JkP6dTKfHHMymBN_-0gVn5Ti9YmDFj58QI_OmxPGvy7slxciijccD2SOn4e3sE9omqJ6EJ1xSzzt5-aP50HHvlXzaYsT9IroV82FTMfAiZzypTVGEqxwNy1GmesDRo7nbfaDa-3nfbCt_7cdBq0-RuRrl4qFyICxQF4cgFyAa3LrIm-du829HqJSoppw2tL0n4Bdv_T3lxAe4tu557MuYeZI7jHcaX5voHX1BO1bojdiuKjzFlQ_UASRs102H28e28LPIdLzTK48IIO0lcTjxOdam2fe44vWisyYZw_VVye5ZeclGRy7huS6SnOcrSwjCJndD7Es3PfPap2bQwVLEc7Pgds1m8kk3FsCYm7n2WhA5bPWJNmpap1vKRDteub5WrEaSXC43lygviF0epGR1-k6KuPlXppSL5Pttev3bP4JAalj3Nak3UuSofyBQm8fWYmy6EfMZ8RR44vZjyVtteeW-sfIyJR04q_2MYYh-4JrLZPjpfyJM1jo5mmudEKVNGS2rkuIBeVpFeL3-iVxbkx-NX53FU8B8nV6aLqDb1uF-imtGlVy2YhEMPFfioavfbxqkG6v0apS4R6wzbXotwooWPwuCoFq-ieiTvhDXL3FCEHxX-d02e9CSl2wVHm33fH4hJu-ThH6KoGXnYVEJqu8JeaH1saPYiRFMRIuQcXx-pVPpvokTUbSgbJeJJQAlKvJ8p2IPNeIp7uG90uQyugdQDHmWmfhJHXhwPAc9FQX4jPLWBrvvEIXmtSfuqPWn-XpgtkB3M8QmOn0cYO6NptpAmAeDFAZwXQthg6BGOckQ_K6PYIWMhmz4f7Kdgc3a-r-XnlC7ivy3OnsUodfOLkESeO_68tXh7Mu-7VCg-RvYiwbjF16MfpT9OgbHvljDP3eUGGwPx4e2MNd7bwxi_Q3P4LmhxGRINyp6DP-HgOiGGnexz99XGhfjY9sA-oXC8o2BstAnz4DsigYWk70Tub3p4wThIEIJxYiUZGO3OX5fSqmpLm6m328XNMWMZzt-WJR8H9qbj1nXm7lxsNpgX01l8cPR2eyGiMr1jNtqJftGS8lW7XDRDu2uwXObbres2f2RY0XypbPVWwlFl82KpJaZadcUTc5gxMxWEHJSbKoPvces-jeC2CUARw5vMpBNRLxWKu-Pa30V2YDDCySFr4SbD8-BDR6lNyXPNX3BJ2MdIy-PjdolDY4u4d_ho4lylk41y8P8555jsLR_2gnisWuaGpPhUNTtqeG9l7KQche5JQ1Phs82GI1XTyTHYjtj3ZgmWdu9Kk2QmQ1FEzhXld5GpzxX5XWSPVI3PWc_ZqrX3Hb4uYr8_e3kpjVg7KX1nIiWOsuAz2HeD51GCcCAz-GwIfqGUF8hWrTy9eO5kDQ_jbluhy0Q68DaUpHt7_p-t0N-eexhkPe5R9ufkQRYVPjSIv7vjxnTf8eRiD0qK5MyLPbZJb9CfGiS-A5dL02apNJZ6OaD15S6IP-gimAyyk7kBbIx__zgZ403XwzIvhURKewOgcS9Yth8NMG_9v7ltCe2FUbKlxp0KAl3PNxhrReDsHWoBFSGQDpJ501OXxLc3g4mZfqbl8MrvVXHjFYmX4Cty40aB74QoiZKr9Y1bFFGMcRYlpAhx7EQFit0Ih27ulNh3nSt6gxwUOLHjuoGPguQ6yIkXhlFQRMiPSOkD3yEbTNm1mRbXQq6u7AXPGzdwIze8YjgjTNn71QjtrhjaO6Zz86YNC50gfYHJj8xfwd2VvLFXSLN6pYDvMKq06nvTVDN7f7sxFdz91RuvV7VkN3_-VmvL-_0G_TcAAP__MhxOSQ">