<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/60813>60813</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang Static Analyzer misses invalidation of a variable pointed to by a pointee of a global pointer (i.e. ptr-to-ptr, `int**`)
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          arseniy-sonar
      </td>
    </tr>
</table>

<pre>
    Invalidation of a local variable through a global pointer works only on 1 level of indirection:
```C++
void opaque();
int* globPtr = nullptr;

int f1(int p) {
  p = 1;

  globPtr = &p;
  opaque(); // p escapes here

  if (p != 0) return 0;
  return 1/p;
  //nonnull(p); //expected-warning{{nonnull}}
}
```
If `p` is reachable through a pointer-to-pointer, it is no longer invalidated. The following example differs only in 2 lines, and while `p` still escapes, the bug is no longer detected.
```C++
void opaque();
int** globPtr = nullptr; // This is now a second-order pointer

int f1(int p) {
  p = 1;

 *globPtr = &p; // This assignment had to change
  opaque(); // p escapes here

  if (p != 0) return 0;
  return 1/p;
  //nonnull(p); //expected-warning{{nonnull}}
}
```
</pre>
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