<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54659>54659</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Variadic template constructor not called implicitly
        </td>
    </tr>

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

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

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

<pre>
    From https://stackoverflow.com/questions/71654148/variadic-template-parameter-pack-expansion-looses-qualifier/71669096#71669096:

```
template <class... Args>
struct S {
    template <class... T>
    S(T...) {}
};

template <typename... Args>
void callFunc(S<Args...>);

int main() { callFunc<const int>(S<int>{1}); }
```
https://godbolt.org/z/h6eq1od3j

Expected behavior: The given object `S<int>` should be passed to the templated constructor `S<const int>::S<int>`, because it is not marked explicit. Instead, the following error is reported:

```
<source>:10:14: error: no matching function for call to 'callFunc'
int main() { callFunc<const int>(S<int>{}); }
             ^~~~~~~~~~~~~~~~~~~
<source>:8:6: note: candidate template ignored: could not match 'const int' against 'int'
void callFunc(S<Args...>);
     ^
1 error generated.
Compiler returned: 1
```

Tested with all versions of clang up to 14.0.0 for x86_64. gcc also doesn't accept this code, msvc does however, but utilizes the implicit copy constructor to do so (in my opinion incorreclty, since `S<int>` and `S<const int>` are two distinct, unrelated types).

</pre>
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