<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63822>63822</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libcxx] Lookup array size in _BMSkipTable for std::boyer_moore_horspool_searcher is not sufficient
        </td>
    </tr>

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

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

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

<pre>
    In `include/experimental/functionall:174`:
```c++
//  Special case small numeric values; use an array
template<class _Key, typename _Value, class _Hash, class _BinaryPredicate>
class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, true> {
private:
    typedef _Value value_type;
 typedef _Key   key_type;

    typedef typename make_unsigned<key_type>::type unsigned_key_type;
    typedef std::array<value_type, numeric_limits<unsigned_key_type>::max()> skip_map;
    skip_map __table;
```
The `key_type` evaluate to `char`, thus the `numeric_limits<>::max()` evaluate to 255, which is less-by-one for correct array size 256.
</pre>
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