<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/62174>62174</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang will ignore using declarations from qualified names when handling declarators
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c++
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          ChuanqiXu9
      </td>
    </tr>
</table>

<pre>
    See https://godbolt.org/z/8eef5nsEs and the test form is:

```
namespace lib {
    namespace impl {
        template <class>
        inline constexpr bool test = false;
    }
    using impl::test;
}

struct foo {};

template <>
inline constexpr bool lib::test<foo> = true;

static_assert(lib::test<foo>);
```

GCC will accept this but clang will reject this.

</pre>
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