<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJylVttu4zYQ_Rr5hYghkro--CFxkt0ACRIkwQLti0FRI1stRboU5az79R1R8m3jFjEqCBbNyzlnZjhDFqbczgIWESkccdC6aROEt0F4HSTh-A5_Ga-btbGOBHzeulI409Ryugr43TCh1o7cvcJfHWLMTaf7ibckDPjNHqCEqtZA3o0TitBwh-x_F9ceMGAZAnG2cAHLyUL2QG0Q3_g1QXy7h9uYuiSVMbignxmkYz8hpekKBcT1K0Y9rddyQDvReYwapLfnrR9NQDcpoZejo8iVJIRcLcnVc4hfYeWKCNskETlZdQr15oT8k5RdsyYftVuZzpF22xRGES0aQKUsA912FsjWdGQlNkCU2jRXw6T6b7Ck1v2YJS_X79-JsaQFDN0KCOhNbY1uAJ2_EZYg5-Pjj6fF229PN8-PD7_fvS76JdiN3iFr04cMG3Xv64CPctESVRf9urdu3Qd8Wm6xgwxP-DMcHkoTkckwTr26fjW_brft0HixCO0NfbdCApp0mGTFx8K0zoJoApYEbI7m-GAH7IbwfBBBLxBRUBafE_Ha6bd6qYX6LnSpwLa7rYI8WTzwsEt40jI8xzNXIHS3fh7ZkKXTLTahJMro5Y6ShdnAyb_MmReclqLfEUIbvW1M1w6bZO2dmo_8VrSrV5BmA3Y7N9rBT_fQrNUwOhjv5wy51Xv8rEAaJoPA6BKBXGbkRMGJz3eUIwMfGWLPgB500CzWSrjK2GbPMjCkVZWFcZWGwEqyQL3OCswZ78pxlyRfgskzXuZJju1fYGgWRUka8SRhnMVZTuNkDFF6DCxPzP9FH4i0pCERha-MPSjjA0Z2CUZYYPZa6xHGOpHvo_BNmUKohzdQB5SjKGS8KgCO8_BJyBUW2ldY1shuH3RlhoElOOycK9G2Jzm5m9kHShrdjqbEdMzG8OtS0BZ-JOUBwWwnXW00LgLpxiLQ6Wc9yrzvtB8_UfRpLNmXCBqPyUvpTtbclPAN9L_t04gXqYyqzx7awb_0DjkIO6vonJQkHZWwgxIL52PtleSxBJ4eK7l_6cmfhBZL9P_lGvAY3YngXxZRRpGgXxDxZMpOnZbvXddeQLKLRnSBDwQ9LqUKlkJux6PjIORQxFDMf4ugNIzOnrmTcobZz3MxER0etna2qq0oa7cVk86q2cq5tY88u8d3iedxV0ylwZPp3rMNn6u1NX_0e5fd122LFwdsxJzxdLKa0YQllIc5TSgwgCLPK86hSCMpRJlIOlGiANXO8NYRMKbhg3gIbOO9Y_L_FdQzFjKGbk37T8ymMVRRJnkcsYhVJR50UQiNqNW0x5kau5zYmYcsumWLgwozvz0Movv7owG8YFToaqdg5it8f-8IWPo5pdmlxWfijZh5C_4Blj8juQ>53237</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Crash in 'InstructionSelect' llvm::MachineRegisterInfo::getRegClass
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    $ cat test.m
```
#import <stdatomic.h>
int ERequestCount = 0;
#define Total 100

_Atomic(int32_t) _counts[Total];
void foo() {
  double totalRequests = _counts[ERequestCount];
}
```

$ clang test.m -c   -g -O0  -arch arm64 

```
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
0  libLLVMSupport.dylib       0x0000000116a8c057 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 39
1  libLLVMSupport.dylib       0x0000000116a8b125 llvm::sys::RunSignalHandlers() + 85
2  libLLVMSupport.dylib       0x0000000116a8b7d0 llvm::sys::CleanupOnSignal(unsigned long) + 208
3  libLLVMSupport.dylib       0x00000001169b31da (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) + 106
4  libLLVMSupport.dylib       0x00000001169b33c8 CrashRecoverySignalHandler(int) + 136
5  libsystem_platform.dylib   0x00007ff805f70e2d _sigtramp + 29
6  libsystem_platform.dylib   0x00007f983d969000 _sigtramp + 18446743662325891568
7  libsystem_c.dylib          0x00007ff805ea7d10 abort + 123
8  libsystem_c.dylib          0x00007ff805ea70be err + 0
9  libLLVMGlobalISel.dylib    0x00000001183fbee7 llvm::MachineRegisterInfo::getRegClass(llvm::Register) const + 151
10 libLLVMGlobalISel.dylib    0x00000001183fa703 llvm::InstructionSelect::runOnMachineFunction(llvm::MachineFunction&) + 3155
11 libLLVMCodeGen.dylib       0x00000001143b7c4f llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 367
12 libLLVMCore.dylib          0x00000001195ce37f llvm::FPPassManager::runOnFunction(llvm::Function&) + 1007
13 libLLVMCore.dylib          0x00000001195d44a1 llvm::FPPassManager::runOnModule(llvm::Module&) + 65
14 libLLVMCore.dylib          0x00000001195cea10 llvm::legacy::PassManagerImpl::run(llvm::Module&) + 1104

```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJyVlslu4zgQhp9GvhAxKFLrwYfESboDJEiQBAPMXAxKKtnqoUgPSTntefopUfLW8TRiw7BoLv__VXFToavtLGARKYUjDqybtgG9Deh1kNDxO_xlvGnX2jgS8Ll1lXC6bcrpKuB3Q4dGOXL3Cv90qDHXneo73hIa8Ju9QAV1o4C8ayckCelO2f8urr1gwDIU4mzhApaTRdkL2SC-8WOC-HYvt9FNRWqtcUDfM0jHekIq3RUSiOtHjDzWsxzUTjiPVYP09nz0YwiYJinUckwUuSoJIVdLcvVM8SlMuSLCtElETkadSr05Uf5Nqq5dk4_GrXTniN22hZZEiRaQlGWgbGeAbHVHVmIDRMpNezV0av4FQxrVtxnycv3-nWhDLODUrYCA2jRGqxYw-RthCHo-Pv7xtHj78-nm-fHhr7vXRT8EqzE7ZK37KcNC0-c64CMuRiKboh_31q37CZ9WW6wgw4f-pMMnDBORlTROPV0_ml_brR0KLwalfaDvRpSAIR06GfGx0NYZEG3AkoDNMRw_2QG7ITwfIMILIIqQxecgXjv11iyVkN-FqiQYu1sq6JPFgw-7xCet6DmfuQShuvXz6IYunbJYhIpIrZY7S0azwZN_2TMveFiJfkUIpdW21Z0dFsnaJzUf_Y2wq1co9QbMdq6Vg5_uoV3LoXUI3vcZ9laf8bOAIU0GwOgSQF5m5ITgJOc7y9GBjw6xd8AMOmgXaylcrU27dxkc0rrOaFynFFhFFsjrjMA941M5rpLkSzJ5xqs8ybH8i0yYRVGSRjxJGGdxlodxMk5ReixcnoT_Cx-ItAopEYU_GXtRxgeN7BINWuDuNcYrjOdEvp-Fb1IXQj68gTyoHM1CxusC4HgfPolyhQftKywbdDcPqtZDwxIcVs6lsPZkT-569hNVamXHUOJw3I306ygYCz9CeUAx05Wu0QoHQenGQ6BTz2rEvO-Ubz8h-tSW7I-IMB43bxjusOa6gm-g_m-dRrxIy6j-nKGd_EufkAPYWaJzKEk6krADiYHzc-1J8rgEnh6T3L_05k9CiSXm_3IGvEZ3EPzLEFUUifALEE-66uTp8b2r2gMku9mILsiBCI-PUglLUW7Hq-MAcjjEEOb3EGFIo7N37qSa4e7nuZi4xkmY-aOqv0ADln5em-zSXTTpjJytnFv75cPu8bvES70rpqXG6-3eqw2Pq7XRP7zJfWMtvn1gIeaMp5PVLM9rmocQZnjcU1ZEYV1HgsUi4lEdc1FMpChA2hm-ugSMKfggXgLL-PIyaWaMMoaZTftHzKYx1FFW8jhiEasrvOsiCq1o5LTnmGqznJiZRyq6pcVGiQHaQyPG1d8O4O1QX3T4mmJmq8aIqnFbMfHmMw__H4-kDkA">