<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/61849>61849</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Incorrect Optimization On Pointer Arithmetic
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          dkw72n
      </td>
    </tr>
</table>

<pre>
    reproduce code
```cpp
class Ptr {
 int* _r;
  inline void m_set(int* p){
    _r = p + 1;
  }
 inline int* m_get(){
    return _r - 1;
  }
public:
  Ptr(int* p) { this->m_set(p); };
  inline operator bool() {
    return !!m_get();
  }
};

int main()
{
  Ptr p((int*)0);
 while(p);
  return 0;
}
```
when compile with `-O0` or `-O1`, the output returns 0 as expected.
when compile with `-O2` or higher, the output is an infinite loop;

this issue first appeared at clang 3.3, and affects all archs (those i can test with godbolt), godbolt link below:
https://godbolt.org/z/59j8GT1KG

gcc also share the same issue since gcc 9, FYI.
</pre>
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