<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/115845>115845</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Clang][C23] Possible bug in initialization of constexpr variable
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c23,
            clang:frontend
      </td>
    </tr>

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

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

<pre>
    Consider the following code
```
void f(){}

const int x = 4;

constexpr auto a = x - x; //clang: error: constexpr variable 'a' must be initialized by a constant expression
constexpr auto b = &f - &f; // clang accepts

```
but trunk gcc rejects both constexpr variables with the same diagnostic
```
error: ‘constexpr’ integer initializer is not an integer constant expression
```
So i guess that clang should also reject the initialization of the 2nd constexpr variable
</pre>
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