<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/107024>107024</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] "error: ambiguous reference to placeholder" when '_' is used as identifier in lambda capture
        </td>
    </tr>

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

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

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

<pre>
    ### Minimized reproducer

```c++
int foo() {
    return [_ = 42]() { return _; }();
}
```
https://godbolt.org/z/5r7GW53re

### Error

```
<source>:2:32: error: ambiguous reference to placeholder '_', which is defined multiple times
    2 |     return [_ = 42]() { return _; }();
      |                                ^
<source>:2:13: note: placeholder declared here
    2 |     return [_ = 42]() { return _; }();
      |             ^
<source>:2:13: note: placeholder declared here
<source>:2:12: error: cannot initialize return object of type 'int' with an rvalue of type 'void'
    2 |     return [_ = 42]() { return _; }();
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~
2 errors generated.
```

### Further info

Affected versions: 18.1.0, trunk

clang 17.0.1 works ok, other compilers also seem to work ok


</pre>
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