<html>
    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Wrong program output in case of many concept conversion operators"
   href="https://bugs.llvm.org/show_bug.cgi?id=51291">51291</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Wrong program output in case of many concept conversion operators
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>12.0
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Windows NT
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>enhancement
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>C++
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedclangbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>fchelnokov@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>blitzrakete@gmail.com, dgregor@apple.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Example code:
```
template <auto =[]{}> class C;
template <typename, typename = C<>> concept x = true;

#include <iostream>

struct S {
    operator x<C<>> auto() { return 42; }
    operator x<C<>> auto() { return '+'; }
    operator x<C<>> auto() { return 44LL; }
    operator x<C<>> auto() { return 45.5; }
    operator x<C<>> auto() { return 46.5f; }
    operator x<C<>> auto() { return 47L; }    
    operator x<C<>> auto() { return 48ULL; }
    operator x<C<>> auto() { return 49U; }
};

int main() {
    S s;
    std::cout << (int)s << "\n";
    std::cout << (char)s << "\n";
    std::cout << (long long)s << "\n";

    std::cout << (double)s << "\n";
    std::cout << (float)s << "\n";
    std::cout << (long)s << "\n";

    std::cout << (unsigned long long)s << "\n";
    std::cout << (unsigned)s << "\n";
}
```

Clang prints here:
```
49
1
49
0
0
49
49
49
```
which is obviously wrong.

Demo: <a href="https://gcc.godbolt.org/z/dPa4GxYhc">https://gcc.godbolt.org/z/dPa4GxYhc</a></pre>
        </div>
      </p>


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      <ul>
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