<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/84843>84843</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] `<random>`: Enforce `seed_seq::generate()`'s mandate for `RandomAccessIterator`
        </td>
    </tr>

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

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

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

<pre>
    [N4971](https://isocpp.org/files/papers/N4971.pdf) \[rand.util.seedseq\]/7:

> ```cpp
> template<class RandomAccessIterator>
>   void generate(RandomAccessIterator begin, RandomAccessIterator end);
> ```
> *Mandates:* `iterator_traits<RandomAccessIterator>::value_type` is an unsigned integer type capable of accommodating 32-bit quantities.

This example should be rejected, but isn't: https://godbolt.org/z/86qrr5PEa

```cpp
#include <random>

int main() {
    std::seed_seq seq;
    int arr[1];
 seq.generate(arr, arr + 1); // should be rejected!
}
```

(MSVC's STL was also affected: https://github.com/microsoft/STL/issues/4434 )
</pre>
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