<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/61566>61566</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Pointless -Wundefined-internal warning from concept checks
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          timsong-cpp
      </td>
    </tr>
</table>

<pre>
    ```cpp
auto begin(auto&& r) {
    return r.begin();
}

template<class T>
concept Range = requires (T t) { ::begin(t); };

namespace {
    struct R {
        int* begin();
    };
}

static_assert(Range<R>);
```
Here, I'm just trying to check the concept; nothing is actually calling `::begin` or `R::begin`. Yet clang warns:
```
<source>:10:14: warning: function '(anonymous namespace)::R::begin' has internal linkage but is not defined [-Wundefined-internal]
        int* begin();
 ^
<source>:2:14: note: used here
    return r.begin();
 ^
```


</pre>
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