<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/131223>131223</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Clang Assertion Failure in `CodeGenModule::UpdateMultiVersionNames` with Recursive `Multi-versioned` Function
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          bi6c
      </td>
    </tr>
</table>

<pre>
    Code explorer: [https://godbolt.org/z/rvrzh6rdj](https://godbolt.org/z/rvrzh6rdj)

generated by fuzzer

**Code:**
```c
int f_(void) __asm__("f");

int __attribute__((target_clones("default,avx"))) f(void) {
  return f_();
}

int main(void) { 
  return f(); 
}
```

**stack trace:**
```
clang-21: /root/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:1987: void clang::CodeGen::CodeGenModule::UpdateMultiVersionNames(clang::GlobalDecl, const clang::FunctionDecl*, llvm::StringRef&): Assertion `OtherGD.getCanonicalDecl() .getDecl() ->getAsFunction() ->isMultiVersion() && "Other GD should now be a multiversioned function"' 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-20250313/bin/clang-21 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -dumpdir /app/output.s- -disable-free -clear-ast-before-backend -main-file-name example.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=none -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-20250313/lib/clang/21 -internal-isystem /opt/compiler-explorer/clang-assertions-trunk-20250313/lib/clang/21/include -internal-isystem /usr/local/include -internal-isystem /opt/compiler-explorer/gcc-snapshot/lib/gcc/x86_64-linux-gnu/15.0.1/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -ferror-limit 19 -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/example-8fb254.o -x c <source>
1.      <source>:7:1: current parser token 'int'
2.      <source>:3:51: LLVM IR generation of declaration 'f'
3.      <source>:3:51: Generating code for declaration 'f'
 #0 0x0000000003e7dc08 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x3e7dc08)
 #1 0x0000000003e7b5c4 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #2 0x0000702a32042520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #3 0x0000702a320969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #4 0x0000702a32042476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #5 0x0000702a320287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #6 0x0000702a3202871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #7 0x0000702a32039e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #8 0x00000000043fc87a clang::CodeGen::CodeGenModule::UpdateMultiVersionNames(clang::GlobalDecl, clang::FunctionDecl const*, llvm::StringRef&) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x43fc87a)
 #9 0x000000000443408a clang::CodeGen::CodeGenModule::GetOrCreateLLVMFunction(llvm::StringRef, llvm::Type*, clang::GlobalDecl, bool, bool, bool, llvm::AttributeList, clang::CodeGen::ForDefinition_t) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x443408a)
#10 0x0000000004436e68 clang::CodeGen::CodeGenModule::GetAddrOfFunction(clang::GlobalDecl, llvm::Type*, bool, bool, clang::CodeGen::ForDefinition_t) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x4436e68)
#11 0x00000000044371e9 clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x44371e9)
#12 0x000000000443a3a4 clang::CodeGen::CodeGenModule::EmitMultiVersionFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x443a3a4)
#13 0x00000000044325a5 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x44325a5)
#14 0x000000000443298b clang::CodeGen::CodeGenModule::EmitGlobal(clang::GlobalDecl) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x443298b)
#15 0x000000000443cd63 clang::CodeGen::CodeGenModule::EmitTopLevelDecl(clang::Decl*) (.part.0) CodeGenModule.cpp:0:0
#16 0x000000000483ad46 (anonymous namespace)::CodeGeneratorImpl::HandleTopLevelDecl(clang::DeclGroupRef) ModuleBuilder.cpp:0:0
#17 0x000000000482ad04 clang::BackendConsumer::HandleTopLevelDecl(clang::DeclGroupRef) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x482ad04)
#18 0x000000000643bc44 clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x643bc44)
#19 0x0000000004837528 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x4837528)
#20 0x0000000004b00005 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x4b00005)
#21 0x0000000004a8398e clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x4a8398e)
#22 0x0000000004bedf9e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0x4bedf9e)
#23 0x0000000000d5391f cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0xd5391f)
#24 0x0000000000d4b2da ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#25 0x0000000000d4f47b clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0xd4f47b)
#26 0x0000000000c17ff4 main (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0xc17ff4)
#27 0x0000702a32029d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#28 0x0000702a32029e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#29 0x0000000000d4ad85 _start (/opt/compiler-explorer/clang-assertions-trunk-20250313/bin/clang-21+0xd4ad85)
clang: error: unable to execute command: Aborted (core dumped)
clang: error: clang frontend command failed due to signal (use -v to see invocation)
Compiler returned: 254
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzMWV1v2ziz_jXMDUFDouQPXeRCteO8BdrTounpuTQociRzI5ECSblJf_0BKTmyXKfb9F0Du_CmFs2ZeZ7hcGZEMmtlpQBu0fwdmm9uWOf22twWcsFvCi2eb9daAIanttYGDEpyjObv9s61FiU5oltEt5UWha7dTJsK0e0PRLfmYH7sF0b8heYbRFe_P51mKMpRlFegwDAHAhfPuOx-_ADT_4Co_3hMQV_4RDlaRP2HoyiXyuFyh-jqoKVANMO7HbPNzo8gSktEqTeTvOsV-tm7HXPOyKJzMExbOWYqcDteawW2lxRQsq52iK7Z4WnQEj64PDGGll4xxgZcZ1QPZLS33IxWGybVVBBPJF8E8Sh55HnqDOsYf8TOMH7ZJyjKec1URWgclo9ujdYO0W1dHxrSGv0XcP8YJvlhWSC69S6-BzV--6hFV8OMty1K8jhbLb0yDx73gkmOkvwodfrQC_ZD_9sK5uBjVzv5DYyVWv0Pa4KDT5Tc17pg9QZ4jegac62sO7Wx7RR3Uqt-Qu7neCb9jw_OSFV9gRLRRfBejnNrwXgBjBbRJ7cHc7-ZVeDWTGkl-dGSdzb24yePBCV3FbjcHm2ejEt7SmP4IVhdYERpMITvN9judVcLrPR3XABmuPFSh14KBC5fNFNEl7hksgYxQ1H--cNd_nCHbVc00mGGi67CBlptHHYan20p6fZdMeO6GZb159WV1nbe0VvMlMBS8boTgN0eMDfM7nHB-GMfQ3SNWwOt0RysBYGt7kw_7CWZtZrLsDVNp7DlRrbO430IYSi6xscHivJohqLss9GVYQ1mpuoaUM4OEajbEHG6aWUNhryklyEKCTuumSXOdOqR0IjOoyROEN0WfttsjyGNCecxJs7Itgb8tFrsFinp1KPS3xWppeqeSKU6TKCRjujiL0w8RCGNh8Ha1oPpXNu5mSWYCGlZUQMpDQAmvAZmCLOOFFBqA8Q7CZTAxO9dUsoaiGKNT4-saf3mwKQxUGvOPHbSaAE1biXHpJWc1HCAGtP-QVrSSsCkKQ1rgLRaKufz60ZpBZiUDXN7AsYojUlZtoRr5ZfHoWSjFSal0sToTgmpKuLn9kMHMIW2QJhtMGnC1jEdd9oQVktmwWJSduq7VII4T9SiZEMx6bMd4W3nPUgWKSauUxAGQir2FAQUXUWkKjV5lEqgZHOiHxPxnZmSDIGNkk06SFRgvDLpt--mEgUmZa-pX_3eU0J66v2KYFJyfQDDKvjFHAN9XJJhKf-biOoz3jH_-ZgKi6FYTaR9tg6af9qC35DDFrxoq7Nerw-k-u-mvg6r4pxYxVq779N9wFBxjuh22Ccv-wPRbTyfRTMPbDb7-c-F-T-Dgif_hf_MY5h6Qc-vpd9uApNPFJMSjNGG1NJnzjjDpKxUx09jc0ZnMSalfZQt0cIQvgf-SKQiVVOG-Ku1IUKySmnrJLeYHMCHufwBpNa6nQzY2scsE8JYWWGy2e3u1-vdf_Jvd7vN_-VftnS33r7f5Q8fUbKJMdEetWt85hnyBlmVBZ2nM43JE-YYJesh5yZ3KMpjn0gnY0nui2-o5rwzBpTDLTMWDHb6ERRGdCmVQ3SJopxekE5Qks-D-IcP3z7i91_w0G_5IqlLLIDXbHhEdFn2mpJfarofNKgKc98xltq8ogcjmkQ4eoqO_yWwFDxanVRx-2z7L5-NVC5Ulq99bVqNkwz7vtPWGWBNKLtrHEj7Irz6R0sMou-ipwFk36F6CvEZhWLOU_wgK8Xq_zAlam9qFRCtsZWVz5s7N_Qrfc-Xe7C9hB36qij83xugg4FlRFlCo5TOaTRw67fyhU1Zy4LPrJ4tAuYgMiJOpgqzRVZy3Lq9ASZ2j7Ku36Y9yI_a03O46XKBKxvovRV2ulyMiudTxXS1LBPMCt8IvUltEBzVLn5SGxdvVhgXo8LlVGGSQbZ4m8IgMipcnUZYmpR8tWTXbrYvt9l9E_53zfZ1Nt5AfHRLNnFLmqTR6k1uuQf3yawNMAc-_Z209heZnRL--tzC4IVXXVhoffHfUUt-fNn8IK070zUBv9VmA6VU0uPbXS-3DU4c3r5pEkdnLl7AYvVGF-dCmE_liXNfddhF955771_gIu-E0UXxmYuWMWRvcdFdI13vh3GjHXn8nrf68W-s7mCoJddi7rmNzOkZc5aw9K3MT5PSv5-_ZzjyT8740zmb_9nK_3sZe04j4_SccbYq_ozx6zyvyCVbFSOX-RkXLhbJW7l81e0H_y4_nBSdSL-cSQU6s5YZN_MdGL50iHZs9jysxQTWKmEiDc0DU1o9N7qzWPna3YYmOJug8223Nu-btu6H--7z1xjvje7aUN4y3GN618lagLkAbTmFRpmIJvv9XX8ostbKdk04Iv4DENdZ_B7suPiTjmqRJgVPJ1Q--7eo_OHrFOsDNGx4w5iWpSvBHoCNsLOz4FjO6aVynPeltg_TJ-Cdg_z01PJKPg5wXsDSae9Q-L-T9Lg1WjlQ4gLaq-LskYw4pwWcrZJsBVOn9pbfK-uY4nDZr68Tu2ZL3KMduUxLcgGizCZcBtQjpcNwRDll8BPlaxaZHuXIYVJWIzFPsrjEnMe74Z7kpH82hj37vJGs-Z6Z8eUkuQut4mRs-rZ9FSo91pFJOmWSFlQwfFyCdfw15I7Tl42G1fW3cJzUZ_ELtBZnnbLW9dqH25M7zgvhJow8XEridH6GqUyXQwk_-nc4qvCmhzuk37J4HY8GfKNHJ9Ux4vGyLNNwf3Yd872B0fzZmz3NRPbGk5ggMipcnSuENMK7nZfZWceM252Q-20TkJ6YyM4WnInVHPfKr7Vm3kQP4JhTcDiI9V86xYoasNMY-o2AuW4apkS4oSu0cSA8Lq4NhEskEK-pCiO4HLLtUc9wc4ZFF6yM506dBUwOYQwAy5PU59UfU95w6woBD52npxeoN-I2EVmSsRu4jZdpnEU0mkc3-1uIswXQVTyfL5Io5rGYF_MoXa6iNGXZapHdyNujz2icRvNothIxTYrFqlzyNI1jhtIIGibrmd9oM22qm3BPdxsnMaXJTc0KqG24mqd0uD2gaL65Mbfheq_oKovSqJbW2VGFk64O9_m9xHyD18Fl40Xolsm6M94bGC2iNxwdLSL8Xbo9_gK8M1YewMuHaeTlStNPOr7T3XSmvv3zu8rBDYdb-v8BAAD___GaFBQ">