<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/102053>102053</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            fatal error: error in backend: failed to perform tail call elimination on a call site marked musttail on arm32 darwin
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Un1q32
      </td>
    </tr>
</table>

<pre>
    used test case from #63214

```c++
void name(int *params, int *program, int r, int g, int b, int a) {
  auto fn = (void (*)(int *, int *, int, int, int, int))1;
  [[clang::musttail]] return fn(params, program, r, g, b, a);
}
```

compile with:
```sh
clang++ -target armv7-apple-darwin test.cpp -c # crashes with all 32 bit arm architectures except armv4t and armv5
```

output:
```console
fatal error: error in backend: failed to perform tail call elimination on a call site marked musttail
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: clang++ -target armv7-apple-darwin test.cpp -c
1.      <eof> parser at end of file
2.      Code generation
3.      Running pass 'Function Pass Manager' on module 'test.cpp'.
4.      Running pass 'ARM Instruction Selection' on function '@_Z4namePiS_iiii'
 #0 0x0000000005dd91f8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/llvm19/bin/clang-19+0x5dd91f8)
 #1 0x0000000005dd6fee llvm::sys::RunSignalHandlers() (/opt/llvm19/bin/clang-19+0x5dd6fee)
 #2 0x0000000005d4d59e (/opt/llvm19/bin/clang-19+0x5d4d59e)
 #3 0x0000000005d4d55b (/opt/llvm19/bin/clang-19+0x5d4d55b)
 #4 0x0000000005dd39d7 llvm::sys::Process::Exit(int, bool) (/opt/llvm19/bin/clang-19+0x5dd39d7)
 #5 0x0000000003db0ac3 (/opt/llvm19/bin/clang-19+0x3db0ac3)
 #6 0x0000000005d537d9 llvm::report_fatal_error(llvm::Twine const&, bool) (/opt/llvm19/bin/clang-19+0x5d537d9)
 #7 0x0000000005d536c6 (/opt/llvm19/bin/clang-19+0x5d536c6)
 #8 0x00000000044ce474 (/opt/llvm19/bin/clang-19+0x44ce474)
 #9 0x0000000006d91d6a llvm::TargetLowering::LowerCallTo(llvm::TargetLowering::CallLoweringInfo&) const (/opt/llvm19/bin/clang-19+0x6d91d6a)
#10 0x0000000006daf6a6 llvm::SelectionDAGBuilder::lowerInvokable(llvm::TargetLowering::CallLoweringInfo&, llvm::BasicBlock const*) (/opt/llvm19/bin/clang-19+0x6daf6a6)
#11 0x0000000006d996ff llvm::SelectionDAGBuilder::LowerCallTo(llvm::CallBase const&, llvm::SDValue, bool, bool, llvm::BasicBlock const*, llvm::TargetLowering::PtrAuthInfo const*) (/opt/llvm19/bin/clang-19+0x6d996ff)
#12 0x0000000006d85950 llvm::SelectionDAGBuilder::visitCall(llvm::CallInst const&) (/opt/llvm19/bin/clang-19+0x6d85950)
#13 0x0000000006d7b106 llvm::SelectionDAGBuilder::visit(llvm::Instruction const&) (/opt/llvm19/bin/clang-19+0x6d7b106)
#14 0x0000000006e16343 llvm::SelectionDAGISel::SelectBasicBlock(llvm::ilist_iterator_w_bits<llvm::ilist_detail::node_options<llvm::Instruction, false, false, void, true, llvm::BasicBlock>, false, true>, llvm::ilist_iterator_w_bits<llvm::ilist_detail::node_options<llvm::Instruction, false, false, void, true, llvm::BasicBlock>, false, true>, bool&) (/opt/llvm19/bin/clang-19+0x6e16343)
#15 0x0000000006e15bdb llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/opt/llvm19/bin/clang-19+0x6e15bdb)
#16 0x0000000006e13de2 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/opt/llvm19/bin/clang-19+0x6e13de2)
#17 0x00000000045a2251 (/opt/llvm19/bin/clang-19+0x45a2251)
#18 0x0000000006e1294e llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/opt/llvm19/bin/clang-19+0x6e1294e)
#19 0x00000000054c97b4 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/opt/llvm19/bin/clang-19+0x54c97b4)
#20 0x00000000058e9ba2 llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/llvm19/bin/clang-19+0x58e9ba2)
#21 0x00000000058f0a13 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/llvm19/bin/clang-19+0x58f0a13)
#22 0x00000000058ea896 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/llvm19/bin/clang-19+0x58ea896)
#23 0x00000000064ac252 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) (/opt/llvm19/bin/clang-19+0x64ac252)
#24 0x00000000064cd0c5 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/llvm19/bin/clang-19+0x64cd0c5)
#25 0x0000000007e368f9 clang::ParseAST(clang::Sema&, bool, bool) (/opt/llvm19/bin/clang-19+0x7e368f9)
#26 0x00000000068e89d6 clang::FrontendAction::Execute() (/opt/llvm19/bin/clang-19+0x68e89d6)
#27 0x0000000006859ba4 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/llvm19/bin/clang-19+0x6859ba4)
#28 0x00000000069b3b7e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/llvm19/bin/clang-19+0x69b3b7e)
#29 0x0000000003db0739 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/llvm19/bin/clang-19+0x3db0739)
#30 0x0000000003dad991 (/opt/llvm19/bin/clang-19+0x3dad991)
#31 0x00000000066a30c9 (/opt/llvm19/bin/clang-19+0x66a30c9)
#32 0x0000000005d4d53c llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/llvm19/bin/clang-19+0x5d4d53c)
#33 0x00000000066a2b06 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (/opt/llvm19/bin/clang-19+0x66a2b06)
#34 0x0000000006661367 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/llvm19/bin/clang-19+0x6661367)
#35 0x000000000666180e clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/llvm19/bin/clang-19+0x666180e)
#36 0x000000000667febf clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/llvm19/bin/clang-19+0x667febf)
#37 0x0000000003dad06b clang_main(int, char**, llvm::ToolContext const&) (/opt/llvm19/bin/clang-19+0x3dad06b)
#38 0x0000000003dbc0e7 main (/opt/llvm19/bin/clang-19+0x3dbc0e7)
#39 0x00007f8fed239088 __libc_start_call_main (/lib64/libc.so.6+0x2a088)
#40 0x00007f8fed23914b __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14b)
#41 0x0000000003dab525 _start (/opt/llvm19/bin/clang-19+0x3dab525)
clang++: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 19.1.0-rc2
Target: armv7-apple-darwin
Thread model: posix
InstalledDir: /opt/llvm19/bin
clang++: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang++: note: diagnostic msg: /tmp/test-c84746.cpp
clang++: note: diagnostic msg: /tmp/test-c84746.sh
clang++: note: diagnostic msg: 

********************
```

[test-c84746.cpp](https://github.com/user-attachments/files/16502302/test-c84746.cpp.txt)
[test-c84746.sh](https://github.com/user-attachments/files/16502303/test-c84746.sh.txt)

</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzUWk1v4ziT_jXKhYghUR-WDjk4TtydQXoTJJlZYC8GRZVsbkukh6Ty8e8XJCVbdJyOnekd4A2MWKZKVU89LFaRFIlSbMUBLoL0Mkivzkin10Je_Mmjv2N8Vorq7aJTUCENSiNKFKBaihYFOM5iHCVBeBWEs_5_FroPDfCl-djWZ8EqxEkLAc4Z1yjAsw2RpFUBnqOhQYqVJO3QIoeL1XBRDhckwAUKpr1uhEinBao5CuIrFODcGgtwHuBZgIudxZGt_vKDryLARRTEW_2WlUvaEL4K4lkQz9pOaU1YE6RXQXqFJOhOclTzAOc7t0b-WF-sH9YHg3-rPphe7TE3ppOKdsMaQC9Mr41tX1KteykLzfKNzjWRK9CIyPZ5ek42mwbOKyJfGLfdN6GbDTqnpu8QlUStQVnliDQNijEqmX0UEUnXTAPVnQSF4JXCxulMNCK8spfpL4CLTm86_R4yFVyJBlxrTTRpEEgpZBDP3AViHJWE_gRembaasMZEnkAbkLWQLTLEI2rgQsNaxolmgiPBEXGtimlALZE_oULbjrLm7m-vZ4_XSHVla7xEZbdCEjZCaqN_rfVGGcB4EeDFiul1V06oaAO8aJrn4et8I8X_AtUBXjClOlABXlhCGKdNVwHSa3DEWi-0JBRcNMBGCgrKjCMlOumaLZVKCcqIhgrJjiNFJdvoiYP8qAn9iaqu3WypDCdBWNy74EJErroWuDbA0elh4DRGRmMQz0HUQXyNNkQqkIhoBLxCokY1GzoMG8m5qACtgIO01Ls7sbnz0HHO-AptiFIowNNFx6ntnXvT8INwsgIZ4KnprVZUXQNGasAT4GnvdXJI2ezhB7rhSsvO6XyEBuxVr7AejAV4GiTh8n8Sk3Du2eOSMcZMoxvOAY5DFL6Gw19aVUVU58h2sh3e6k25i3vJuLZd8OT6Md8JSfKyFEpLMEM82-UOl3kWYqP7iImKAC9KxgO8sB10bhouw9ferskFW2DRHrCsBjgE7KHjj2zFSfOd8KoBqazRk2wb1Z5t7NtOqrSAExRaeU9h_E5hWp6mMC09hckeO3FRTQ93mx1o7sf1K9OuBtj8K0RzIlHGigcjHcOIqzIkND5aYS_vKcx8v9J4WhUjv1yKWtpkuXTJchyITy-MAzJ5VfeBeLqT1qSHabqPKaPZSQozmnkK87HCJKGQTJOjFfbynsJirDCriqjKyIi1J5v_bsULSDbUbftrTprmSfgUHpA1YkPLDa-F5bZwPB-Nu4e1xW2GeOjjJnVGshHubVq7mn277FhTgXQ3GgPmhj-Ln6Rs4Gv45yNDl0QxetkI-nMIntkpQdMj91yL9rqkyOr6GNc-6hfTdGmmm-PoHum7-os0HexCfvf9iZvzTwLlXstZp9eGty-SY333yME-OXlapOEx5DwzxbRh4h01phqOqDkFnrXuwYt9eNMyCo8KSwvPgzYu0l9DZ4176LzUn0GUxUn8AbqbR2jGrbsA8FCyhim9ZNrMYoRcvixLZmZR832JCuwE0rZwUcFSbIwhX3TksgmumjQKvAuzJjHfWrp4PRSfQXztPWNlXdt_KGw3Gk_rfNe3Xuene52fllV5ZOfPbALpkSovALaT0y_FqEPhwcz2YMYV4E9hyo7f8R-ErhmHAZEH8929U3EaGB5Or7QnKcE4jY6vxE7eU5jvOY6LBH7h-C2sCH37t9w3YDy03rwhTWgxLRP0oUGzchlBPYjxi-B622Nw2F-Z5FCUZBxDi3uDZ1hI_T_BclY9WP66JK9DEsVHwPph13h-f_ZNJ0KyFj1IeI8pkhfjetWMgmwE7qbd7Abe7wBm7XrA_EKaEIpTjEabR9ct05dug-PObZLgfHT7ipEVF0ozqq75inHopz0jke9AKpCPQCRd37m07s2QRqJmrf4N-CdSbgr0idAt4atDIqOBrs0M6gFqv3lgdransCdhtq0_48KkZafYMzxAPef6Xkuvbj3X_ZhcsAYe35SGtq84SlfuTsfZ3x0sN3tPmlX75kUyDcth7T56qIKadI0png1o-OTB-Lq3-d6lueCqa0GeOmt0weJFkz_xSWgV0vRXFl2A2F2BJ0m4auwezZ-c7YXZ7PFpLriG15Mrn8PggfQK9BTiLK-LMch7IhXMHp98CI_QEm_FevrKtbflgfHLcA55UWVjMAtp_N7GXb9JALTTcOIuSq_csz71radFSRJ_QNoNXWmmXoRT8OwPQyH_GO6JneUAeAj9al2UcTkFLz85LDugz4KS97jeOXJirDvDHrJif2NlGheI0mjZEuYn65mU5M0kmnhO10Tu1mj9iPTatvPYkwD29scA_X3DuCJVURw_c-rlPYX-gjkjcUhPoNDJewrfb-LFdJRX55Ko9QNQ8QzybRj_2x1FUkPz5vE87KkupeV692alsEyfssVkoXhY4z3ncRl6A7WS7HnIaPN5NBdtS3i1P2APBsU2o7tVD2m8XL6rU9scvn1guaSvr1HkfpRm6WDyvd0YsKHmCZuGpZbELcHs7T11pGnM6BFydN-IzHbZbvaFbSVHlsemXyiyLIqz6Yds2rFL3uW_gWJvoO89aAQ-miL8QnS2tzd5qsPWH8_hdN_hPIRTHf5DlOpjb_8Q5S3ztli82U5LmuYvoFr0s8pd1G0IMx3e7zkfS1AfGv-Qpjz0kqq_uZxl0xrK-iNIV6NrrwwcyP8f0fsv0nRKqrR-e8RM95N5mJUOxFBvBmB22M_ebxwK0fQ59Et7CL1ND1S-VwJpCFNk4JxSt8xDntahsE7rvIYKx0WY52i5bFhpshuReklJ0yxHdhpWZon7phMlJpnVjUmY52PNSbivOUpKX7PlMgm_3d5czpd4gifpJyaixKMkifb6qUxxipzyU6g2j231jt6Ubl88b9-gorqfciHax17_Etq-J4dXZrq7AjQNjf1OATp_RlogBYDYaLY0toWeQSomOIqKSTQJzyXF7q5behnb79_U9hJrCaRCrajsnhHaCMVe3S0792oaqK6YhX-Yi0Mec2HWNzNUbVebqFUrq6Mn_h98RscA-lfus6en2fw7evp-jRZ3t7d3_33zX9_Q4ub2-hE93dnmyz-_oYfr-7uHp2B40X1_6JV5rswQ-_C1-VZAArKVFypEdscQjmcBL3S7Mf9B6XOaJ9Mks--of4OaA6c2juqS39Uxh45rBOnlvqfpVYDzXxyK6BTIc6I1oWt3AgEvatbYAxFRloY4DvF7_ib6Ve9Gt29UrX-Dzfgd2Z7Js-oiroq4IGdwEU0xzvMiCvOz9UVWp1UaJRWpYxwXdZJjUkUFxllWQ5pM8zN2gUOchHmY4jDKcT4pQlynWV2FeZHVaZ0ESQgtYc3EDL6JkKsze0DkIgpxmMZnDSmhUcMJK3lhD5OU3UoFSdgwpdXuOc10Axf_2uEYe1u2MUYu7Zx1srn4-mmY3t_nC_x_AQAA__-dvkcN">