<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/91433>91433</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Compiler gets into an infinite loop after commit 8e7618aa2165
        </td>
    </tr>

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

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

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

<pre>
    Recently a bunch of our internal tests started to time out when being built and I was able to bisect it back to 8e7618aa2165. Consider the following code:
```c++
typedef double __attribute__((ext_vector_type(4))) double4;
#define double4_zwxw(__A) (__A.zwxw)
void test52() { double4 id10996 double4_zwxw(id10996); }
```
If compiled with a compiler that does not include 8e7618aa2165, the compilation completes in under a second:
```
$ time ~/src/upstream/0a0cac6dbd0ef67eb473f85a968bbf4ebea5220d-linux/bin/clang -c -mavx repro.cpp -o repro.o

real    0m0.044s
user    0m0.012s
sys 0m0.032s
```
However, if we build with a compiler that includes 8e7618aa2165, the compiler seems to get stuck in an infinite loop and is still building after 10 minutes:
```
$ timeout 600 ~/src/upstream/8e7618aa2165-linux/bin/clang -c -mavx repro.cpp -o repro.o
$ echo $?
124
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJycVM2O4zYMfhrlQiSQ6Z_YBx92ZmB0r32BQJboRF1ZCiR6Mumhz17ITtrudNsCBQRb-iSS4veRUinZsyfqRf0i6redWvgSYm_uiz_vxmDu_c-kybO7g4Jx8foCYYKwRLCeKXrlgClxgsQqMhngAGxngrAw3C7kYSTrzzAu1jEob-Ar3FQCNTrKZ0ebSDNYhlHpbxlp6dgUrVJYNPUBXoNP1lAEvhBMwblwy-50MCTKL0K-CflFNHIbWuBLHivK9ysZmsCEJcc6nRRztOPCdDoJbAW29MGnd9Ic4ikfFthWArttPMwqUT7cCSwNTdbTc-f06-3jJrA9nb7k89vssIHdZvMerFnpqXGN2IE4vjztwZpCdl3z2d8Dzk7KFxDHt09JbsuvE-gwX60jAzfLF1DPdaZKMZhACXxgsF67xdB3vAp8XQndTBTb4Ne5I6YE1sPiM-cKEungzd-ZfnJSbWL_JnBIUQsclmviSGoWOEgltdKNGY2kqTnSWB3Lqa1V17TjOFU0kqoRpdk765cPgcNovcBBO-XPsNewn9X7B0S6xnDQ1yvsw2MRHtHXbyTlAADkLA-yqtKGLoniH2iBDzTd04aUT-RTQj-FG71TzPTYCW60lu0_EPzgNf0LsRQhEc0pl_WZGBIv-lumV3mwfrLeMoEL4bo2hs1NZJ3bguYqVxNThELCbP3ClP5Lh9xzjZQ_luOv1_zflGMFpC8BBFaiHDawwOrTrXamL01XdmpHfXEs6qJq6rLdXXpJk2oJEWls2kJTTVLS0dRlUSmiotjZHiVWspatrMu6bA8VtgUeyxI73SnstKgkzcq6g3Pv8yHE886mtFDfFVVZ7pwayaX1LUP0dIN1UyDmpy322WY_LuckKuls4vSnF7bsqH99ynYmzn3A4QdSraLoMM-Wv9N-t0TXX5ivq044CBzOli_LeNAhC5BjPX77awy_kGaBw3rDJHBYM_g9AAD__9lIueM">