<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/117974>117974</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Clang] Confusing diagnostic when using `fsanitize=function -mexecute-only` flags together on ARM targets
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Il-Capitano
      </td>
    </tr>
</table>

<pre>
    When passing `fsanitize=function -mexecute-only` to Clang on an ARM target, it prints the following error:
```
error: invalid argument '-fsanitize=function' not allowed with 'arm-unknown-linux-gnueabi'
```
The error happens because `-fsanitize=function` is incompatible with execute-only memory, but prints the target triple as the reason. I would expect the error message to be the following in this case:
```
error: invalid argument '-fsanitize=function' not allowed with '-mexecute-only'
```

The diagnostic is created here:
https://github.com/llvm/llvm-project/blob/69d66fafec968b17f84e30bc09faffb3dc8e5f15/clang/lib/Driver/SanitizerArgs.cpp#L416-L423

I think a good solution would be to print `-mexecute-only` (or `-mpure-code`) as the reason for the incompatibility if it was passed to the compiler driver, and print the target triple otherwise.
</pre>
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