<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/161983>161983</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Variadic concept defined in terms of another concept improperly cached
        </td>
    </tr>

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

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

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

<pre>
    The following valid translation unit

```c++
template<bool b>
concept bool_ = b;

template<typename... Ts>
concept unary = bool_<sizeof...(Ts) == 1>;

static_assert(!unary<>);
static_assert(unary<void>);
```
causes clang to fail with

```console
<source>:8:15: error: static assertion failed
    8 | static_assert(unary<void>);
      | ^~~~~~~~~~~
<source>:8:15: note: because 'void' does not satisfy 'unary'
<source>:5:17: note: because 'sizeof...(Ts) == 1' does not satisfy 'bool_'
    5 | concept unary = bool_<sizeof...(Ts) == 1>;
      | ^
<source>:2:17: note: because 'false' evaluated to false
    2 | concept bool_ = b;
      |                 ^
1 error generated.
Compiler returned: 1
```

Commenting out either static assert causes the failure to go away. This was introduced by 9583b399d85cacdfa0a41f798ab44abaa3981bbf @cor3ntin @zyn0217 

See it live: https://godbolt.org/z/r5nPr5TKe
</pre>
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