<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/77189>77189</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Deducing `auto&` from `const int` in template parameters is impossible in partial specializations
        </td>
    </tr>

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

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

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

<pre>
    ### Code to Reproduce
See https://godbolt.org/z/rhKsWKdPz .
```cpp
#include <type_traits>

template <auto& Value, int>
struct test : std::false_type {};

template <auto& Value>
struct test<Value, 0> : std::true_type {};

int main() {
    static constexpr int v = 42;
    static_assert(test<v, 0>::value); // error ?!
}
```
```none
<source>:11:19: error: static assertion failed due to requirement 'test<v, 0>::value'
   11 |     static_assert(test<v, 0>::value);
      |                   ^~~~~~~~~~~~~~~~~
```
### Explanation
Clang is completely unable to deduce `auto&` in the partial specialization, leading to this failure. GCC accepts this code, as it should.

Note that replacing `auto&` with `const auto&` fixes this, but shouldn't be necessary.
</pre>
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