<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/102314>102314</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
             clang refuses to match dependent reference non-type template parameter in partial specialization
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Rush10233
      </td>
    </tr>
</table>

<pre>
    The following code used to be accepted but is now rejected after clang-16:

```c++
template<int, class T, T> struct S;
template<class T, T A> struct S<0, T, A> {};
int i;
S<0, int*, &i> r;  // OK
S<0, int&, i> s;
```
The diagnostic shows that `template<class T, T A> struct S<0, T, A> {};` is not chosen for the instantiation of `S<0, int&, i> s;`.

```c++
<source>:5:15: error: implicit instantiation of undefined template 'S<0, int &, i>'
    5 | S<0, int&, i> s;  
      |               ^
<source>:1:34: note: template is declared here
    1 | template<int, class T, T> struct S;
      | ^
1 error generated.
```

I'm not sure but it seems that implicit conversions like `int & A=i` should be taken into consideration. Note that non-type dependent pointer argument can be successfully matched as shown in the fourth line of the test.

GCC and MSVC accept the code.

[https://godbolt.org/z/jcMP8938e](https://godbolt.org/z/jcMP8938e)
</pre>
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