<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/61779>61779</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Nested requires-expression in lambda causes ICE
        </td>
    </tr>

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

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

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

<pre>
    The snippet below is derived from GCC's test `concepts-lambda14.C` causes an assertion failure. Unsure if it's a minimal repro, but it's as minimal as I could get it for now.
```cpp
// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s

template<typename U>
void f() {
 []<typename T>(T){
    static_assert(requires { requires __is_same(T, int); }); // expected-error{{}}

    return 0;
  };
}

void g()
{
    f<int>();
}
```
```
clang++: /root/llvm-project/clang/lib/AST/ExprConstant.cpp:15330: bool clang::Expr::EvaluateAsConstantExpr(clang::Expr::EvalResult&, const clang::ASTContext&, clang::Expr::ConstantExprKind) const: Assertion `!isValueDependent() && "Expression evaluator can't be called on a dependent expression."' 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 -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>:4:6: instantiating function definition 'f<int>'
 #0 0x000055959dac438f llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3c7438f)
 #1 0x000055959dac20cc llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3c720cc)
 #2 0x000055959da0f238 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x00007fb100f43420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #4 0x00007fb100a1000b raise (/lib/x86_64-linux-gnu/libc.so.6+0x4300b)
 #5 0x00007fb1009ef859 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22859)
 #6 0x00007fb1009ef729 (/lib/x86_64-linux-gnu/libc.so.6+0x22729)
 #7 0x00007fb100a00fd6 (/lib/x86_64-linux-gnu/libc.so.6+0x33fd6)
 #8 0x00005595a130bd37 (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x74bbd37)
 #9 0x00005595a0450617 clang::ActionResult<clang::Expr*, true> calculateConstraintSatisfaction<calculateConstraintSatisfaction(clang::Sema&, clang::NamedDecl const*, clang::SourceLocation, clang::MultiLevelTemplateArgumentList const&, clang::Expr const*, clang::ConstraintSatisfaction&)::'lambda'(clang::Expr const*)>(clang::Sema&, clang::Expr const*, clang::ConstraintSatisfaction&, calculateConstraintSatisfaction(clang::Sema&, clang::NamedDecl const*, clang::SourceLocation, clang::MultiLevelTemplateArgumentList const&, clang::Expr const*, clang::ConstraintSatisfaction&)::'lambda'(clang::Expr const*)&&) SemaConcept.cpp:0:0
#10 0x00005595a0450ba2 CheckConstraintSatisfaction(clang::Sema&, clang::NamedDecl const*, llvm::ArrayRef<clang::Expr const*>, llvm::SmallVectorImpl<clang::Expr*>&, clang::MultiLevelTemplateArgumentList const&, clang::SourceRange, clang::ConstraintSatisfaction&) SemaConcept.cpp:0:0
#11 0x00005595a04510bf clang::Sema::CheckConstraintSatisfaction(clang::NamedDecl const*, llvm::ArrayRef<clang::Expr const*>, llvm::SmallVectorImpl<clang::Expr*>&, clang::MultiLevelTemplateArgumentList const&, clang::SourceRange, clang::ConstraintSatisfaction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x66010bf)
#12 0x00005595a0cb8428 (anonymous namespace)::TemplateInstantiator::TransformNestedRequirement(clang::concepts::NestedRequirement*) SemaTemplateInstantiate.cpp:0:0
#13 0x00005595a0ce9196 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformRequiresExpr(clang::RequiresExpr*) SemaTemplateInstantiate.cpp:0:0
#14 0x00005595a0ce9d7e (anonymous namespace)::TemplateInstantiator::TransformRequiresExpr(clang::RequiresExpr*) SemaTemplateInstantiate.cpp:0:0
#15 0x00005595a0cbd193 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformExpr(clang::Expr*) SemaTemplateInstantiate.cpp:0:0
#16 0x00005595a0cf1a1c clang::Sema::SubstExpr(clang::Expr*, clang::MultiLevelTemplateArgumentList const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6ea1a1c)
#17 0x00005595a0d03306 clang::TemplateDeclInstantiator::VisitStaticAssertDecl(clang::StaticAssertDecl*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6eb3306)
#18 0x00005595a0d56098 void llvm::function_ref<void ()>::callback_fn<clang::Sema::SubstDecl(clang::Decl*, clang::DeclContext*, clang::MultiLevelTemplateArgumentList const&)::'lambda'()>(long) SemaTemplateInstantiateDecl.cpp:0:0
#19 0x00005595a02f6b05 clang::Sema::runWithSufficientStackSpace(clang::SourceLocation, llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x64a6b05)
#20 0x00005595a0d04b21 clang::Sema::SubstDecl(clang::Decl*, clang::DeclContext*, clang::MultiLevelTemplateArgumentList const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6eb4b21)
#21 0x00005595a0cb6a86 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformDeclStmt(clang::DeclStmt*) SemaTemplateInstantiate.cpp:0:0
#22 0x00005595a0cf7759 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformCompoundStmt(clang::CompoundStmt*, bool) SemaTemplateInstantiate.cpp:0:0
#23 0x00005595a0cbc8b6 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformLambdaExpr(clang::LambdaExpr*) SemaTemplateInstantiate.cpp:0:0
#24 0x00005595a0cbd3d9 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformExpr(clang::Expr*) SemaTemplateInstantiate.cpp:0:0
#25 0x00005595a0cf64ff clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformStmt(clang::Stmt*, clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::StmtDiscardKind) SemaTemplateInstantiate.cpp:0:0
#26 0x00005595a0cf7759 clang::TreeTransform<(anonymous namespace)::TemplateInstantiator>::TransformCompoundStmt(clang::CompoundStmt*, bool) SemaTemplateInstantiate.cpp:0:0
#27 0x00005595a0cfa85e clang::Sema::SubstStmt(clang::Stmt*, clang::MultiLevelTemplateArgumentList const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6eaa85e)
#28 0x00005595a0d4b298 clang::Sema::InstantiateFunctionDefinition(clang::SourceLocation, clang::FunctionDecl*, bool, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6efb298)
#29 0x00005595a0d4967f clang::Sema::PerformPendingInstantiations(bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6ef967f)
#30 0x00005595a0316fa0 clang::Sema::ActOnEndOfTranslationUnitFragment(clang::Sema::TUFragmentKind) (.part.0) Sema.cpp:0:0
#31 0x00005595a031768a clang::Sema::ActOnEndOfTranslationUnit() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x64c768a)
#32 0x00005595a01b2253 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6362253)
#33 0x00005595a01a5dda clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x6355dda)
#34 0x000055959ece4f78 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x4e94f78)
#35 0x000055959e5498a9 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x46f98a9)
#36 0x000055959e4cddd6 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x467ddd6)
#37 0x000055959e62d537 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x47dd537)
#38 0x000055959b0425a6 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x11f25a6)
#39 0x000055959b03e3ca ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#40 0x000055959e3360ad 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
#41 0x000055959da0f720 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x3bbf720)
#42 0x000055959e33696f 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
#43 0x000055959e2fe1ac clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x44ae1ac)
#44 0x000055959e2fec4d 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+++0x44aec4d)
#45 0x000055959e3068fd clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x44b68fd)
#46 0x000055959b040a50 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x11f0a50)
#47 0x000055959af4c4c5 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x10fc4c5)
#48 0x00007fb1009f1083 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x24083)
#49 0x000055959b0390de _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+++0x11e90de)
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzkW11z26i7_zTKDSMPAr1e5MJ1kj3d0912mnTPpQcBcthKoAWUJt_-DJJsC9luk47d_8x_Z9zG4uXh97w_IEyMERvJ-XWQvAuSmyvS2Uelr-nfrLwqFXu5fnjkwEjRttyCktfqGxAGMK7FE2eg0qoBv61WAcoMsNxYEKSQKkl5a01Yk6ZkJIoXqyCFgJLOcAOIBMQYrq1QElRE1J3mC_BFmk5zICogbE-MgEZI0ZAaaN5qFaAVKDu76zW7bmLAe0BVVzOw4W4AqJQGUn1bBPAmgMsghcOHtu3Ygu4CdAc-f_kzwEsQoITWRG7WlEYgNJYF-IYG6F2A3iEIwsq8SEueQyXrFxA-cS2qFzfHjLT6_y1v2ppYHuCVfWm5JA0HXwJ8O_Q-KcFAFaA8QAUIsndDKxgEPp3y4Kag_CFAxX4YAMBYYgVdD2ILUK75P53Q3DhiYPewXguzNqThA4kVENI6SvgdCLKb7beBd_7ccmo5C7nWSrvF3OfGfSZsubU1t52WAAZ4B8iN2j7NZvSsbgZWtwMmjFQBXjlUPZsDojmZrbaOPvaKGnQzqO5OK2UDdFfXT03YavU3p-5xHHdXizJAd8v7hwDd3T63eqWksUTahbMFvIwSjKEjVCpVg2ESXgZ46caO355I3RHLl2Y7t-9D-cnRn7npahug1KmAuklTysv7h5WSlj_vRhyjM13rf4VkznB6Ug7scuc9Ti4oEuYvUnf8hrdcMu50Phiao5-CACFHhRvjZvCBHaUBJTJAmXNpQEldcwaUBASwLRVnIuOsRYBQgLLeWTkb3erTh9vl_S0wXdkICwgou43zVKUtsAo8Wtsax0tvbhthH7tyQVUzqupQY8KYjhtnmkQyICStO8aBfeSAamIeQUnoV6sJ5U5mbR8SKDeGM2BUp4dmN5MYo6ggljOgOwkM1aK1I-R7S-hXwLrG6X5ogosAFp-02mjSAKI3XcOlNaNtqba3JdW0ouY65M9trTTXW_sKd2HMhFZ38muA7koh9-bnzBSEG_aN6CqMQbgBoXJ0Sds66p1tO7swIGycLEAYPudpSEwTDhEnwDdCWl6D8B6E4YbS0CpV00ciZIBvvgvPDTaStOZRWRBWVNVKh0yQjVTGCmpAWEkV9oL1m-fRL8CrUbzbWBY5gQV4xVUV4FvQEm24BsQCLhlQFahEzYeRaBy5J4CXcYCXqZOuGOxbECvkBlSdpL1BM14JKQbbRtk0WmTboIkwBPAZQgiTpEgKRmiM8wr0VtX7jnkxw5dPWkjb6_xhMJx8P0iTb2tlrOakGf1wCJagd56zaD5A7-AzppmDt4uGDn80w48gpcfwr2pOZNd-lPdiI0kdoLyTfa5moFZulUugdWA8tMhHCyuEc7BypvOZU_XE9csA73-IZLVbNB8l6Y0ZY94Yd2H_b7cEHpfIqjKCsIpxjCBYrzU3Vmm-1nbkc4jmz3m6TuOwFrJ7DjeyGzpa-6g5YQujFrDnJYpjBD1OYm8ZEkEIS6CJMPwV9KmjnPaUYwxh6VFOPMoFr_KkAKRUr0I-oYxQnhQe5XROOdtp_dU0M-TTzHw5QFix9G00Ma5Y6tHMJ1ZCIgxLhrNzW2cWl46st24xXRfGCUyjzEu3fVwZUzJezZMtWjrXt7pz8cnlQdq5Mq5Pv5q48EGsMBXpqbj5PxjhlQX3vCGHSf5P0nB2w2k9JvQBwnRaHy8_KEoGkl7nH11txQf-xOuHseRcjknrg3CFxkDyWGFxarlTnPT67UcEKBsKeReFDwqfCd1iqOt-KIKfhLP6oYL-7eLvKz4Xex3vq2EXdhhyXQqCc78pCQKrR06_nlu0-8S21Jq8fObVoR_uJzgDms65b0hd_8WpVfp909bHXdhNmoP5OU0Nyv9M5Ia_QU8_Fnc0E3cEywrMBTqs81od_Hulfea0kqbQqWO_YUU4Qp6-aJnHKHfrEqnkS6M6A9x-3bR9WTn66Zbz97vSVo27uQdNpKmUbv7kxnL2ediwN8NWbcL19txkVPDh4OXW2A7X4scND_uM8CIq0qmgHzTnO3gBXv0Uj7czNkfM5nCn7Pe8nZ14zg7L-Bn0cjnAycyQWFTgi8v_xAnFT8BPffhVRCJ6PG7dd6U5dTRykPReHS7O7-ycOB48Z888JhnEGPo-MmJ0wfbQiP4SRrhdphV0OJhxw2bp8qB3eRHWSofcYy33WUtSWOSgP6PbB_3t5nut-2TR925P50bLoqSuS0K_rivp54SZ_g9Z37Hr6d-17k7Bft44jtZHuzJ0u0c-YfAOw3Gj9_cUqEpLmBw3et3J_xP28b6rKkEFH08b7geXzb9bVL5W_hewk5g4jqZ2guDMBeISRd_x81-s5wt4imPQk0A0C9QpyS-fKJ187m1jD2U5tL45YKNZ4VJlWVJcnI2ValrVSXbIit_TW0CpVP1mtmZlTEnz8vLa-dBHlcOcNm1_u4bieUWA2eU1dLaKAM0KmiqNq-ri8A8Na2JQF1rcrXAjDCWabd_AvElQ89Lpv8QTsxlbJE_4dzLFazX3H60IHQ9eMpiVTXGJivw4kxN53Y15_Gb3DuNHNcCkcz95l0cH9cz_XoD_yrHn8V_M-C_S7MRxxSeund194pIJudlLwy0coPxymB2kKWbslzA4SisCj2NeUvtR3kr2ser9pu7RfpHC3mmyOdyV7yc-fNmO2EaEAOWLlmi7gFtHOuo1OJqBy9KcvBHc7q3umYtB6rB4kvRriKhEKPH2rJ_6d36T7w-q7V33sCz82JJ_Ov7Jan_b4Ab-plXX9udTR86T9vL4Q7Gu5u-bVul-l8UvFAVw6tj05OAXHRFJGCMHcujvFpw4G7205-LEQfIwT6uLglMeV1nuH6wx_huXy_GFxlAJcNpZvtyeMV4AacwLB8RDmnhIk7jIiZcf77TbOEh2BOqFQKaVw-CBTD2QMWWMpWCWVd2yQ-Cj_LhET3N1EVuO08zh9BjJPEZSxBKc-a8oesh7fp52eWpeRXj8XuQkI86Yw-cxME3JRQljlJAUUBqtG-Jo5McPvh_JwWm334ZW_XHIZfiIosrB9PgofD4wx5SArfRX0UMfKvLvHskfMJX6BwqOxrjr9gonpsUT10cTVOzdqeAYp5Cwcx4UDWuPRrSKVqppiGRzrz6qxP5OimtTrVudOBlM5GO1kJsxjwwa3k1Yr-nzcxQNDyUxgq5NP3yUojfYNaytJsKabfeMHKlr5xRKT_rdkEm1tpxe1HrF2dTvqjyuj2h-6yJDcKKKY3crxgPrTt6Titcvnjh_9RkTLkuHeGr5MZqbWJF6ReW_zkRm1eNJW8Ce4FDFI0JPCq7XHTlImVtpetF8NtENOPWq7jtDl161M-HtrCkhJo5tz6DiuVxozN4ql99VaU4L5XdVHry__F5o3tlBS4QeL6-9QY6jsfwaadKYedL06zEM07w6Kc2byXevcjhSMpzSwi-U5vkLlLh04vHkl84KFEiScf-5LVG2-Puwsjx4YX8qbZ-_KHHQPOxedUiqmMY0AQ712ReHlaPtLZ77V9yqCOYYrNe1KF0sJtquJ0hee-kthrm3mYvndVcBGQcD_fNLmDvq--W3d9iv2DVmBS7IFb-O0hzCOIFZfvV4TaoCJRmvqjhhhPOCZzHM8hwTniCc8ORKXCOIMMQoRziKonzBU85SFxMxzgiM8iCGvCGiXjh7Wii9ueovVF-nUZYVVzUpeW36X3ggtLvd29_qXrmW0aOqcXOy79heSNg1uLrDPSU3V_q6v8JddhsTxLAWxpr96lbYml8PVxh2v1AI91fKgZBgqIy2Pwt5v7q96nR9_fM3x3te_z8AAP__7ci85g">