<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/67529>67529</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang-tidy: modernize-use-using fails when type is implicitly forward declared
        </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) fails to convert typedef to a type alias when the type is implicitly forward declared. The new type alias (BPtr) is an alias for the class itself and not a pointer to the class. 

Before
```
class A;
typedef A* APtr; // OK
typedef class A* APtr2; // OK

typedef class B* BPtr; // * missing
```

After
```
class A;
using APtr = A *; // OK
using APtr2 = class A *; // OK

using BPtr = class B; // * missing
```

Should be
```
class A;
using APtr = A *; // OK
using APtr2 = class A *; // OK

using BPtr = class B *; // * missing
```

</pre>
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