<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/67531>67531</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang-tidy: modernize-use-using leaving fragments of the tidied code
        </td>
    </tr>

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

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

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

<pre>
    clang-tidy check modernize-use-using (LLVM 17.0.1 and before) leaves some fragments of the tidied code which renders the code uncompilable (at best). A single function pointer typedef works fine but when multiple type aliases are defined the issue shows up.

Before
```
typedef void (*abcdefghijklmnopqrstuvw)(double);
typedef int (*ABCDEFGHIJKLMNO)(int);
typedef void (*x)();
```
After
```
using abcdefghijklmnopqrstuvw = void (*)(double);
typedef int (*ABCDE;
using ABCDEFGHIJKLMNO = int (*)(int);
typedef voi;
using x = void (*)();
```
Should be
```
using abcdefghijklmnopqrstuvw = void (*)(double);
using ABCDEFGHIJKLMNO = int (*)(int);
using x = void (*)();
```
Obviously, there is some relationship between the leftover fragments and the length of the type alias name
abcdefghijklmnopqrstuvw (23 characters)
typedef int (*ABCDE; (20 characters + LF == 23 - 2)
ABCDEFGHIJKLMNO (15 characters)
typedef voi; (12 characters + LF == 15 - 2)
</pre>
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