<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72883>72883</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            `<ranges>`: `drop_view::begin const` has O(n) complexity 
        </td>
    </tr>

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

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

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

<pre>
    https://github.com/llvm/llvm-project/blob/f9c47e89c1d6433e3bc28e756e08ebc600a38946/libcxx/include/__ranges/drop_view.h#L104-L108


The wording of `drop_view::begin const` in [[range.drop.view]](https://eel.is/c++draft/range.drop.view) is:

>   _Returns_: `ranges​::​next(ranges​::​begin(base_), count_, ranges​::​end(base_))`.

Note that "_Returns_" is used here, which means that the implementation only needs to return the value of `ranges::next` and does not need to obtain the value through `ranges::advance`, which will have 𝒪(n) complexity in the case of random-access-sized but non-common range.
Currently, only MSVC-STL handles this situation correctly.
</pre>
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