<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/109652>109652</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [ARM][AARCH64] clang doesn’t support mfence in aarch64 or arm?
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Zhenhang1213
      </td>
    </tr>
</table>

<pre>
    I find neither AArch64 nor ARM supports this, but x86 is ok;  but in gcc, it‘s ok.  And I don't find  reference about this case
[godbolt](https://godbolt.org/z/5q4K8vrME)
```
__asm__ __volatile__("mfence" : : : "memory")
```
</pre>
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