<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/144642>144642</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang]Crashes when initializing an rvalue reference array of an incomplete class type
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          Rush10233
      </td>
    </tr>
</table>

<pre>
    Generated by fuzzer that deletes the class declaration body to create incomplete classes.

Probably starts from clang-9: https://godbolt.org/z/6fE8nzsna

Simplified test:

```c++
  class MoveOnly;

  void foo() {
    MoveOnly (&&mo)[1] = {};
 }
```

$clang++ -fsyntax-only mut16.cpp
```
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-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>:5:28: current parser token ';'
2.      <source>:4:14: parsing function body 'foo'
3.      <source>:4:14: in compound statement ('{}')
 #0 0x0000000003c1ff08 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3c1ff08)
 #1 0x0000000003c1e04c llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3c1e04c)
 #2 0x0000000003b6e6d8 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x000074d51ea42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x0000000000c3f490 clang::Sema::LookupSpecialMember(clang::CXXRecordDecl*, clang::CXXSpecialMemberKind, bool, bool, bool, bool, bool) (.cold) SemaLookup.cpp:0:0
 #5 0x00000000068d808a clang::Sema::LookupDestructor(clang::CXXRecordDecl*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x68d808a)
 #6 0x00000000068638bb checkDestructorReference(clang::QualType, clang::SourceLocation, clang::Sema&) SemaInit.cpp:0:0
 #7 0x000000000687da58 (anonymous namespace)::InitListChecker::CheckArrayType(clang::InitializedEntity const&, clang::InitListExpr*, clang::QualType&, llvm::APSInt, bool, unsigned int&, clang::InitListExpr*, unsigned int&) SemaInit.cpp:0:0
 #8 0x000000000687f4c2 (anonymous namespace)::InitListChecker::CheckListElementTypes(clang::InitializedEntity const&, clang::InitListExpr*, clang::QualType&, bool, unsigned int&, clang::InitListExpr*, unsigned int&, bool) (.constprop.0) SemaInit.cpp:0:0
 #9 0x000000000687faaa (anonymous namespace)::InitListChecker::CheckExplicitInitList(clang::InitializedEntity const&, clang::InitListExpr*, clang::QualType&, clang::InitListExpr*, bool) (.constprop.0) SemaInit.cpp:0:0
#10 0x0000000006880317 (anonymous namespace)::InitListChecker::InitListChecker(clang::Sema&, clang::InitializedEntity const&, clang::InitListExpr*, clang::QualType&, bool, bool, bool, llvm::SmallVectorImpl<clang::QualType>*) SemaInit.cpp:0:0
#11 0x0000000006880625 diagnoseListInit(clang::Sema&, clang::InitializedEntity const&, clang::InitListExpr*) SemaInit.cpp:0:0
#12 0x0000000006880597 diagnoseListInit(clang::Sema&, clang::InitializedEntity const&, clang::InitListExpr*) SemaInit.cpp:0:0
#13 0x00000000068884d6 clang::InitializationSequence::Diagnose(clang::Sema&, clang::InitializedEntity const&, clang::InitializationKind const&, llvm::ArrayRef<clang::Expr*>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x68884d6)
#14 0x0000000006880ff5 clang::InitializationSequence::Perform(clang::Sema&, clang::InitializedEntity const&, clang::InitializationKind const&, llvm::MutableArrayRef<clang::Expr*>, clang::QualType*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x6880ff5)
#15 0x00000000065b65db clang::Sema::AddInitializerToDecl(clang::Decl*, clang::Expr*, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x65b65db)
#16 0x000000000621099e clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x621099e)
#17 0x00000000062265fc clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62265fc)
#18 0x00000000062292fa clang::Parser::ParseSimpleDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::ParsedAttributes&, clang::ParsedAttributes&, bool, clang::Parser::ForRangeInit*, clang::SourceLocation*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62292fa)
#19 0x0000000006229827 clang::Parser::ParseDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::ParsedAttributes&, clang::ParsedAttributes&, clang::SourceLocation*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x6229827)
#20 0x00000000062f6b46 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62f6b46)
#21 0x00000000062f747e clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 24u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62f747e)
#22 0x00000000062ff20d clang::Parser::ParseCompoundStatementBody(bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62ff20d)
#23 0x00000000062ffc4a clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x62ffc4a)
#24 0x00000000061da536 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61da536)
#25 0x0000000006226a5f clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x6226a5f)
#26 0x00000000061d28d7 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61d28d7)
#27 0x00000000061d36ee clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61d36ee)
#28 0x00000000061dd25f clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61dd25f)
#29 0x00000000061dead8 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61dead8)
#30 0x00000000061cceba clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x61cceba)
#31 0x000000000456c23d clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x456c23d)
#32 0x000000000487dd3a clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x487dd3a)
#33 0x00000000047f997b clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x47f997b)
#34 0x00000000049727c3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x49727c3)
#35 0x0000000000d97015 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd97015)
#36 0x0000000000d8efdd ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#37 0x00000000045ddf39 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
#38 0x0000000003b6eaf3 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3b6eaf3)
#39 0x00000000045de159 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
#40 0x00000000045a0e1d clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x45a0e1d)
#41 0x00000000045a1dd1 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x45a1dd1)
#42 0x00000000045ac6bc clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x45ac6bc)
#43 0x0000000000d93911 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd93911)
#44 0x0000000000c4c1e4 main (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc4c1e4)
#45 0x000074d51ea29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#46 0x000074d51ea29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#47 0x0000000000d8ea75 _start (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd8ea75)
clang++: error: clang frontend command failed with exit code 139 (use -v to see invocation)
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzsm91y27gVx5-GvsHIQ4LfF75gJHubbTJxo0xn7zwgAEqoSYALgI6Up-8AoEyRkmUnZdKdaXe8sUzi439-ODg4BCGkFNtwSm-8-J0Xr65Qp7dC3nzu1DbwYRhelYLsb36jnEqkKQHlHlTdt29UAr1FGhBaU00V0FsKcI2UAoTiGkmkmeDA1AVaACwp0hQwjkXTmgquLFXXnl94fnEvRYnKeg-URlIrUEnRmCJ8s8i9sABbrVvlhYUH7zx4txGkFLW-FnLjwbtvHrxLqtuMf1McuebWrGlrVjFKgKZKm4r2upf47gd78J358QvQq_4onugnXu-98J0rC8CTYARUQngw82AOvNSVB89lgb2TeDBphAdzL34XePEKeOHKFk5XrjFgPh113muBkTXQKQGLSu25RruFMA03nQ6Sa9y2k3r3H26L9S1QXdkwDRAouw2QtBVSG8oTSkxvu_Iai8aDd3X9dPi1aKX4F8Xag3dMqY4qD94BxIkZnboj1A2lRGoLSoQftUSYenAJWklbKTBVihKgRCfdZVMTKSUws-4hOw4UlqzVZmjXGuFHQLqmdWPgX3t-fi_FRqIGILnpGsq1kQw8eCdao8l4CKupXNBdWwtJpblmPUHLjj968K5k_HDtAG9DviJZLSKw2ICFMI2htjVNdrrt9LUCi8aYDhaLXZYskGoWjrYXrhjXtAaLiovFE5WlUNTcB4s1WCw2GC-0EDXeIsa9cHVRpCmsOGrVVmiwqLCohVwQhjZcKM2wcn1YsKPLXrjsaYa3nl8EBtHoWljEXljAzGDCnZSUa9AiqcwUFI-UAw-mxtNg6vkFPFM98sIiMP_YaoxvQNVxPExQD6bWzU398GJ9xoExXXScmKmqqRk_Nw3S3uVhaqaC8XoY-sDf-Yf_QhxUlZ8B64ph4YWF2iv34V4yrq2vfHHelg2FJPr6IJSWFDV2ri0B49rOR9PrjzuNB9_5u17ToDiYKKZ-hM8pXtYU8a79xNdsw1HtwazjNo4SUAvTxWz6jIJBHxzpKxOakAwsjU99plg8Ubl3gv6GOKlNN1lPa1RmKbimO20DTFj49n_Xfti3n0YkDiiKYAz93pKalR6822XJQxItasa73WLDO3cDXytxnVjJtsogODoW7OOwinLfRXYHck0b5D59EOKxa9ctxQzVH2lTWvlHRZd__GEMkGRFce3BwvjC-Pao8t8ZJ6ZIKUT9-m87XtdY1MR8NqqcnjOM4mOTkoxkfoYumbSiSssOa_GqPfM4TS9pGINkLDgJs7IEeEvx4yDtM62opNxOviON_-hQ_WXf0gnrtY0OHwS2y_z0prHfTFXH8T1n5zwtHYtKCYozYz7igu8b0SnAUUNVa-NB7lo2TX1gSi-Ndip7jOaPQkq0d0KP5ZsKDNXsGyW3XDO9B1hwpftAMiloWr7dtfLUtQYKtt4QD4r79XszvwZveg4Ddt69oZuTChepZRNqVYThj1OzUmobxI156lfAmw_UdOpypVsp2mv_FYb5lCFC6McZ3u7ammGmDyV-BcPL9b6filn4_DGVzA-D9IeoTC-OeDzHhhMjfp6nTX8P03fdoLr-JzXx733T1l64PNdaeNsH5wv0gim9BMagz_KoUWzq_VwUF_XBqb44T_9K-sKJviwiydlu7YKzpn92dq2y91a9GbPLHzo0ucSo5NESYFaez7QaO8_BauM7c63qFopb1Q2yaDqkVRW_Fdk9lZWQzX-H2MdOo7Kmr4N7YXLPmChZaAPScWYXl0lMyvOZXUHIAEZ-ES6FO6Z5Pkk9H6b_c0uc1sGSccoHAz_P6bGOe_v8ePR5NezaFJWm8vC3kAUnhdaSlZ2eZghDoVN3OOmBfKFNWyNN3_NKvOREx7XuhPyM-Ia60DTfqDsaA6txJgphElf4VVa_SdG1Yxr37uHa3DUPIqfGDbj6B7Bzxo9gfx_U0_LTPH3qjr8EtwU64M4muHNYoYs22t28Ywd9yQnPU50yOMv0deqnJQ75xFt5vjYys_E2RAfe-ZR3BtO3hoK_COlfxS07bF55MITjhBhWSRkll_30sCH2SU6j6SiAns0_x6vgWjcHn4FRZxfD10OBqfS2gTkbBr5_YOYCb9EO4IMJ-DRKL69d58H_VUjPRslwGCjBCaUK-uSi6mW_cftM650gew9ms-YhTsegMpyqxNHlYH_X70xPVb6aWZ16BRb9o-B8tuFoCKxwnIAHBMXh5QBxsG1FK2aSx2l8PUogfl5W9QFpOsxmt2Mxn5c6CgOjeJpbobj6f241Z26F4mrAnUxcEmbk9bX-kzxyzPdcU-neaMy8cr86hAXGVCm7h18xw2A2nzQYBkjpBFKY0Dc_G41YvTiJZ0c19a2fh8rAGFBlE1QEvjJ9b3fOfV7MIX8WntkAGBMHAPkEAEUkuwjgi2g_0Cdan24IfGrRnx2915ME5Dng2a2QM-nHsOnwUZCupu-bVkht18c5Vzdn27Pl43e3SYAxLU9X7mL95cU9pDPv12ZQaXUMKke5YhQnGIajLGgpCP2N8sJO2cMWDMWdpv2l_mzHDNr63gdtowwtylJCwhHBO2lWKk7OiJtTlut4kDVKyaK0yvO0HCNzHb3nSqPnHcMptZftmM8ne3GD9FHGFeUpTHE43l2zIgcLnp5X5-yShfMFkF7UIHmUAPkkT_0gBhgHDw1i40eU4_3QLZKHXO55K3R0DS7t8aQZlTtpg_BkLDyjFSHgAHgZfLGz-vwT1uFdyokVk41g00afrR1lrjkgkj1RefqWYPzOOIoJqcLcHdMaGj0cbXmQFqW966aTO8zihQVGdV0i_PhQ8XEsdh33TrIMlqJpECfTmXl2yJTuy4nW9I4MgCM4WjK-6SO8G8_nCg8PeLcLAvdHiRTDD8oW7xGOCpsLD1oiptXh9qQ5VNfG6d1zbn-_f4N1iMXWZxxwW8WDaY2akiB7eOeACmaHkyy_i_LMYGTToyioCo_G4dyBE3fnc8fXqKL1fsTy8rjNdZ7GyRy8PJ94FA3iHPwve4R9a9wiqd0L47NDH_ljasinAXmRmh0qdLLEHVCOIvOkoinw0jPthaLF5HjAs2EzrPHW1mf_iSb5BwoICb6XxO-iVC9j-F2U5iH9hXdpp1H3edhbxMyIMz59FL5IrveNn8fPEBr4wQk_nJT4Ja2ro8-jlf7MEv8S91_Ib66s0jIZiIWThCLMg97jDinFQbGNFEU_z19fdedJIoycQezk9F-EAxoBI3OW3lx7Q2_x-PAizEn-nYcXbZWhwWTaII188PBg6jzYk-oPR7a8uQsaHXWRTtMslMbANT7PiNgWXX_H98ICUCnNmlA47wFVn8YD3Pt0hVhNCfjK9BbQHTPeQigIQusqnaJg8QS0AIpSwI4y7fz4zPoVuQmNU6ArehOksQ9hkkbh1famIkEF44j6OSSwyn2YlThKA5hkCY7zLL9iN9CHsZ8EmZ_4cRRe05RkaeYnWUBSiMLEi3zaIFZfG9e-FnJzZY-z3wRRlETwqkYlrZX9VgOEveXQi1dX8saegi-7jfIiv2ZKq6EJzXRtvwrhasQrm8ZQBb5uKQfs8Mqf8Q1AHMgnVHcUyMPZSYDM8g9EZW5Ov-wA9L6lV52sb378nH5v29MN_HcAAAD__71iRJs">