<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/95225>95225</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Capturing constant bit-field by reference is not a constant expression
        </td>
    </tr>

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

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

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

<pre>
    This program:
```
struct U {
    int i : 4;
};

constexpr int foo() {
    const auto & [y] = U{5};
 return [&]() { return y; }();
}

static_assert( foo() == 5 );
```
is accepted by GCC, but Clang rejects it with the error:
```
error: static assertion expression is not an integral constant expression
   10 | static_assert( foo() == 5 );
      | ^~~~~~~~~~
note: initializer of '[y]' is not a constant expression
    6 |     const auto & [y] = U{5};
      | ^
note: in call to '[&]() {
```
Online demo: https://gcc.godbolt.org/z/Mqx1M9589

If one removes lambda expression then the compilation succeeds, meaning that error about `initializer of '[y]' is not a constant expression` is wrong.

The code is slightly modified version from: https://stackoverflow.com/q/78611419/7325599
</pre>
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