<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/71206>71206</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang should warn when building with `-fexperimental-bounds-safety` and `-x assembler-with-cpp`
        </td>
    </tr>

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

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

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

<pre>
    In #70480 the `-fexperimental-bounds-safety` flag was added.

Currently Clang will emit a warning that `-fexperimental-bounds-safety` is ignored when building with `-x assembler`. However, it won't emit a warning when building with `-x assembler-with-cpp`.

This issue tracks adding a warning to detect when `-fexperimental-bounds-safety` is used with `-x assembler-with-cpp`.

We can either have a generic warning whenever this combination of flags are used. Or we could have a more targeted warning:

E.g.

```
#if __has_feature(bounds_safety) // Should warn here
mov x0, #42
#else
#error "oh no"
#endif
```
</pre>
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