<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/133257>133257</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [C][Sema] -Wformat misleading idempotent FixItHint for scanning into const
        </td>
    </tr>

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

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

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

<pre>
    The following code:

```c
#include <stdio.h>
#include <stdlib.h>

void parse(char* in) {
    const char* B = (char*) malloc(42);
    sscanf(in, "%s", B);
}
```

```
<source>:7:23: warning: format specifies type 'char *' but the argument has type 'const char *' [-Wformat]
    7 |     sscanf(pos, "%s", B);
      |                  ~~   ^
      | %s
```

https://godbolt.org/z/Gnqvq4Kvd

produces a `-Wformat` warning that has a `FixItHint` attached, which does not actually change anything related to the code. Such a warning is a problem in interactive editors where the editor shows "fix available", and after applying the fix, the warning is still there.

</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJx8VF2v4yYQ_TX4ZZTIAX8kD37Ix6Zd9XEr9XkM45gKgxdwctOH_e0VdpK9d1vdyBIT5jDMORzAEPTFEjWsPLDylOEUe-ebW6_DSF7He9Y6dW_-7Ak6Z4y7aXsB6RQxsWf5_FX58sn0hwttpZkUARPHEJV2656JL_-XMrp95fL91WkFI_pAjG9lj57xPWjL-A5YfWD5HgBAOhsiPLMHYOIEP-EJO6AxTjK-LTjjOyaeK0OQaDvGt6nkERjnjJdhHo5weEFZfXpP6ReGKRbH4CYvKTUu9jUTey6Y2MMNvdX2ksLO-QEjhJGk7jQFiPeRgPE69QlzozW0U4TYE6C_TAPZCD2-A754PuGsPKz-Wgqz8vQgVQOrj_CB3ujCZ_xm8GvVh9-PHylTfvmAmov8R5A-xjEkA_Az4-eLU60zce38hfHzP4yff7Pfr9-LP65qgY_eqUlSAARW5S8aVf4UDWKPiwAz4qzfvsbftZ0hGCPKnlTiceu17EE5CmBdBJRxQmPuSSh7IUB7j30q58lgJAXRzRInu67h2yR7wNeWOm02etcaGkBb0DaSRxn1lYCUjs4HuPXkaS6xzEDo3S0kcTv9BnhFbbA19FAZrQLsInnAcTT3hRdBp99SNoXv9g5RG5MmPa0fLuMbVh6-DnihdMJ8-4vKOvZTu5ZuYPw8BfKrRZnkncD4GUOgOeBbue3arl5VnWpXBVd8hTLPVxKJUyc2qsx3jO8y1Qi1EzvMqNnUhci35XZXZX2DO9xhm6OqeIVFkW9yImxFUQpFpUCV6YbnvMwFrzeF2PBqTWVR1GXdVaJrsSsqVuQ0oDZrY65DskWmQ5io2QjByzoz2JIJ84PDuaUbzNkkYnnKfJMWrdrpEliRGx1i-Fkm6mjml-qYFCoP32hAVp7gaSkYdDCEatZY0TC6mG7Wy0_pZkK6Kcsp2OiWFyWbvGk-kTs18BhWo3d_k4yMn-e2k-IPXteG_xsAAP__GPqcSw">