<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/82891>82891</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Calling a static constexpr method on a non-constexpr variable does not yield a constexpr result
        </td>
    </tr>

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

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

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

<pre>
    The following C++ code fails to compile with Clang 17.0.1:

```cpp
struct A {
    static constexpr int n() {
        return 42;
    }
};

void foo(const A& a) {
 constexpr int n = a.n();
}
```

with the following error message:

```
<source>:8:19: error: constexpr variable 'n' must be initialized by a constant expression
    8 |     constexpr int n = a.n();
      |                   ^   ~~~~~
<source>:8:23: note: function parameter 'a' with unknown value cannot be used in a constant expression
    8 |     constexpr int n = a.n();
      | ^
<source>:7:19: note: declared here
    7 | void foo(const A& a) {
      |                   ^
```

GCC compiles the same code without errors.
</pre>
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