<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63497>63497</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang frontend C++ crash when using std::numeric_limits without header
        </td>
    </tr>

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

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

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

<pre>
    To quickly reproduce: https://gcc.godbolt.org/z/9qr5s5n4d (assertion-trunk)

```cpp
#include <iostream>

using E = std::numeric_limits<int>;

auto fail(E e) -> decltype(throw e, void()) {
  throw e;
}

int main(){
    return 0;
}
```

Compiling the above code crashes clang `clang++ -x c++ --std=c++20 `, crashes locally using clang-17.0 (a10019a), also on trunk with assertion (see godbolt link)

Note that if we use the correct header for std::numeric_limits (i.e. `#include <limits>`) then the code successfully compiles. 
</pre>
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