<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63465>63465</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Invalid "Substitution into constraint expression resulted in a non-constant expression" warning from clang-16 on
        </td>
    </tr>

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

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

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

<pre>
    The following C++20 code results in the above mentioned error:

```cpp
template <typename, int a, int b> struct c {
  template <typename... d>
  c(d...)
    requires(sizeof...(d) == a * b);
};
template <typename e, int a> struct f : c<e, a, 1> {
 using c<e, a, 1>::c;
};
void g(c<double, 2, 1> h) { f<double, 2>(h, 0); }
```

It works with `clang-15` as well as other compilers and started failing with `clang-16`.
</pre>
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