<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/107843>107843</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang crashes on incorrect code with build compiler returned: 254
        </td>
    </tr>

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

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

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

<pre>
    Reproducer: https://gcc.godbolt.org/z/dj3765YPn (assertions trunk）
```
#include <iostream>
class Base;
class Derived;
class DerivedClass2;
class Base
{
public:
    Base()  = default;
    Base(const Base&) {}
    virtual ~Base()  = default;
    virtual bool operator==(const Derived&) const noexcept {}
    virtual bool operator<(const Base&) const noexcept {}

protected:
    DerivedClass2 obj;
};
class Derived : public Base
{
public:
    bool operator==(const Derived&) const = default;
    bool operator<(const Base&) const = default;
};
class DerivedClass2 : public Derived
{
public:
    bool operator==(const Derived&) const = default;
    bool operator<(const Base&) const = default;
};
class DerivedClass : public Derived
{
public:
    bool operator==(const Derived&) const = default;
    bool operator<(const Base&) const = default;
protected:
    Base obj(const Derived&);
};
DerivedClass2 obj{};
int main()
{
    std::cout << "ok";
}
```
```
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-20240909/bin/clang-20 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -dumpdir /app/output.s- -disable-free -clear-ast-before-backend -main-file-name example.cpp -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -fno-verbose-asm -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debug-info-kind=constructor -dwarf-version=4 -debugger-tuning=gdb -fdebug-compilation-dir=/app -fcoverage-compilation-dir=/app -resource-dir /opt/compiler-explorer/clang-assertions-trunk-20240909/lib/clang/20 -internal-isystem /opt/compiler-explorer/gcc-snapshot/lib/gcc/x86_64-linux-gnu/15.0.0/../../../../include/c++/15.0.0 -internal-isystem /opt/compiler-explorer/gcc-snapshot/lib/gcc/x86_64-linux-gnu/15.0.0/../../../../include/c++/15.0.0/x86_64-linux-gnu -internal-isystem /opt/compiler-explorer/gcc-snapshot/lib/gcc/x86_64-linux-gnu/15.0.0/../../../../include/c++/15.0.0/backward -internal-isystem /opt/compiler-explorer/clang-assertions-trunk-20240909/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /opt/compiler-explorer/gcc-snapshot/lib/gcc/x86_64-linux-gnu/15.0.0/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include --std=c++20 -fdeprecated-macro -ferror-limit 19 -fgnuc-version=4.2.1 -fno-implicit-modules -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/example-338b0c.o -x c++ <source>
1.      <source>:34:2: current parser token ';'
2.      <source>:29:1: parsing struct/union/class body 'DerivedClass2'
  #0 0x0000000003b258d8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x3b258d8)
  #1 0x0000000003b2301c SignalHandler(int) Signals.cpp:0:0
  #2 0x0000725aa1a42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
  #3 0x0000000001abfe06 _ZN4llvm7hashing6detail23hash_combine_range_implIKjEENSt9enable_ifIXsrNS1_16is_hashable_dataIT_EE5valueENS_9hash_codeEE4typeEPS6_SB_ (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x1abfe06)
  #4 0x0000000003a78db1 llvm::FoldingSetBase::FindNodeOrInsertPos(llvm::FoldingSetNodeID const&, void*&, llvm::FoldingSetBase::FoldingSetInfo const&) (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x3a78db1)
  #5 0x000000000793da12 clang::DeclarationNameTable::getCXXDestructorName(clang::CanQual<clang::Type>) (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x793da12)
  #6 0x0000000007954f58 clang::CXXRecordDecl::getDestructor() const (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x7954f58)
  #7 0x0000000007957659 clang::CXXRecordDecl::hasConstexprDestructor() const (/opt/compiler-explorer/clang-assertions-trunk-20240909/bin/clang-20+0x7957659)
  #8 0x0000000006a02d28 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
  #9 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
 #10 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
............
#234 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#235 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#236 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#237 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#238 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#239 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#240 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#241 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#242 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#243 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#244 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#245 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#246 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#247 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#248 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#249 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#250 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#251 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#252 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#253 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#254 0x0000000006a02df9 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
#255 0x0000000006a02e64 bool clang::Sema::CheckCompletedCXXClass(clang::Scope*, clang::CXXRecordDecl*)::'lambda1'(clang::CXXMethodDecl*)::operator()(clang::CXXMethodDecl*) const::'lambda'(clang::QualType, auto&&)::operator()<'lambda'(clang::QualType, auto&&)&>(clang::QualType, auto&&) const (.isra.0) SemaDeclCXX.cpp:0:0
clang++: error: unable to execute command: Segmentation fault (core dumped)
clang++: error: clang frontend command failed due to signal (use -v to see invocation)
Execution build compiler returned: 254
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsXFuTG6sR_jXsC4VqxOj6sA9aXXK2kuM4livZ5EXFQM8ILwNTwKzlPOS3p2BGu9JK68tJfOpINSrZ1nBpvu6vGxokzJyThQa4RcM7NFzcsNpvjb1de_sIN5kRX24_QGWNqDlYlM7w1vvKoXSG6ArRVcF5rzAiM8r3jC0QXf0b0ZX4lI5Hw3--1xjRCXMOrJdGO-xtrR_RcoXu5mgyRckCJTM0Stp380hTqbmqBWCUzqVx3gIrUbpsqrlizuE75gCld4dFC7DyCcT50nl4oK_qopBmzHFbUdWZkjwoFx8xxk0rOkF0ijFKF1hAzmrln2UdtOFGO98-jEKHIHe8eGn3JK2vmcL_-R6h-8aZMQqbCizzxqJ0Ed77sfZKN8M1ZdrAjkPl3xz9lcD5OeRfEdVayhoP3AeDHxjryNzYZJ-eNQrdz1KDg081dv9ORn7UIG8Z-PvtcE7Cmwq1yh-otQd1FZpdsGLnfTZ0ja56FtBZq5y6eRMf-3qpPS6Z1E2IvzJPGNP5iCGdcVMHrHOUzjGi1DwiSo-GPDtFHj--_8tytl5iV2el9JjhrC6whcpYj715PV1Lv62zHjcloiulnvb_kMqaT8A9oivpXA0O0RVmWuD9XOy3gLllboszxh-9ZRwQnePKhrWBg3MgsDO1bYpDT-ac4ZJ5ENjWGjtuZeV7DeS1Z_wRi7qsnqlIeiiZvremsKzEzBZ1CdoH4BjRlakCMm7KSiqwBHaVMhZsKFNMF-RliSFxiSE0oYNkmkwRXWWBh7YdTTDhvI-Jt7JSgHeT0WY0ILV-1OazJkrqekcKXWMCpfTEZJ8wCSiFtAEGq6oApvZV7XuOYCKkY5kCklsATLgCZglznmSQGwskmAq0wCQ4A8mlAqJZCRh2rKwU9HhVYVJaUIazgJ6URoDCleSYVJITBU-gMG0epCOVBEzK3LISSGWk9mFFXjClMMlL5rcErNUGkzyvCDc6sORRujAak1wbYk2thdQFCW2boiewmXFAmCsxKaP_25p7YwlTkjlwmOS1_iy1ID5o6lC6oJh4ZgvwhFd1MCEZDTDxtYZYUIAGGzQQkNUFkTo35FFqgdLFgXxMxGdm8wDASaNRuhi0PQqwQZjUBUoXhcgwyRtJDf2NoYSM00ikBJOcmyewrICvtLHQuCdpufxfXErJbN8O0VVwqsiFZopI98V5KL8-QsE5cZpVbmv8s7iCc0RXrUc-eyKiq_6wl_QSRFe93ulfbXyGgRC9i--2wx8S1Blhf1ScIXg_Myt-FN-Pu88LkvNj1S7IDZOE-lbT38VsZ9qfgoJd-MBP9Xgx-lc84UzvHx8CExIX2kXLbgjUXEBlgYdliZSM2zBbgrXGEiXD8tmfYpIXuuaHM1OP9vrNfCnLSkkufZipaxWnR_coK2KEJXwL_JFITYoyD3PSbkea9DlufUh-9MCNMpYIyQptnJc8lDEhrJMFJovN5k_z-eaX2d-Xm8U_Zh9WdDNf3W9m619RuuhjYoKqvgyLUbuUkDSdZAnvGUx2uFU35BXtkrzfPfXDIntUnM7SAUpnNCy0vLYWtMcVsw4s9uYRwgZuHBISOm4k0DMSQpY068e8kFkndYGbWT7woYMJo7M7h8NuMgg83pXtRWOMaJrgZJfsX2lGhxMxwTFRifmS--KaD--t1D6mER-bXGTy0siyz5v9vjEkcXMstY_7sZCP_R-TCUTvkl0L8jnRi2r0X6mRJn2O17LQTP3CtFBhuEmLqil2IRtA6SyJf14k0VbSmA4Z67MBHdKkVaSJ4TPRqGTGe870RhFg7HIMLz2E12dZDskIb_71bhCMON4yt5W6GAnwTCqahucNN2UmNWws0wVsQhzc__nTcvlu7aegQ2qwkfn9g7Pv1v1NfyTdJvSK5YJ5dv9xs1wOn5iqYfluvZm2IgUslwP_pYLl-_Vos77b_ByKWg2PbTA4ooiNJyLrH3jayqiQK63BN4cNsUxq8c4I-Ku91wHAe-OOHO-lT2h1v2j2Iq0PPhkpEJ21T98Y6LnsXufmQMzP8uFG_WMDDQ8NNJ6mgvUpblatCHIBXDEbc613rISPgeympgA_f3hYwD7ZC9Vhe_XSd87032qmUDo_KPz4pYozys_SstXhWMvRsZbDQT6cHGo5f3j4ANxYEdR9Vu9Ft_YYp911_hzYEdQx7PEr2OPRcPoN2Fvm5gEl7Cr7O-MP6I7xTw7xj1hCBZ002_sDJdZQsladsLbOTVjqPIj5w0NcO459as1NBTHC5m9bIlRPmwpEx4qVmWD9sAQdu-fDw6_gt-akz_PZQ7Oz_1anNnKPhzsZLURC9P2wc669iZE-emvMdP5bJNFRjKzvavziDD3pLAt54BQHLoJi84eHN1aq6WtKYTToKL1YSkMWk5xEaT7tKL1USnsHr-cvW14lQl3cXjjJkdJhF7fXRumoo_TaKB13E--1UXq6remi9MIpPdnWdJReOKWDk21NN_FeOqX9LkqvjVLaUXptlKbdxHttlJ6cHnVReumUdqdHV0fpyelRN_FeOqUnp0ddlF46pd3p0dVR2n0pfm2UDrsvxa-O0u706OooPTk96ibeS6f05PSoi9JLp7Q7Pbo6Sk9Oj7qJ94IpbaQ2l-PSGY5XpcKHOt75wN5g2AGvPWBuypJpESrXUJSgfbwagOMd7DAkNxbinV8QaP9b8LfEx3KcW6M9aLGXjXMmFQgs6jiyixdngujaASZPsQwAS_3UXqh9HmcZQQY4WS1VFBh_3I4t-NrqeCUc0-Hg1QXrG3Gbimk6ZTdw2x_T4WTSp6PhzfaWJcO0P86T0XTAxnk2SEZcMBikLE9HGWeDG3m7_1F8v0_Hg0FPZOM0y7PxIB2J0XSQoEECJZOqp9RT2TO2uIkXr2_7yXgySG8Uy0C5-H9yUNpaiaLh4sbexvvaWV04NEiUdN69iPDSK7idR-PF29rgsNFYam6sBe4xNwLwZ-m337DDTW3V7W-_Ot4q8XRL_xsAAP__OIYrtw">