<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/57412>57412</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang][nullability] No warning when defererencing _Nullable pointers
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          iluuu1994
      </td>
    </tr>
</table>

<pre>
    The [nullability documentation](https://clang.llvm.org/docs/analyzer/developer-docs/nullability.html) states:

> If a pointer p has a nullable annotation and no explicit null check or assert, we should warn in the following cases:
> 
> * p gets implicitly converted into nonnull pointer, for example, we are passing it to a function that takes a nonnull parameter.
> * **p gets dereferenced**

However, I can't get Clang to warn for the latter case.

```c
#include <stdio.h>

int main() {
    int * _Nullable x = NULL;
    printf("%d", *x);

    return 0;
}

```

> -Wnonnull -Wnull-dereference -Wnullability

https://godbolt.org/z/rrGW4h66T

Is there an undocumented flag that needs to be set? Or was this never fully implemented?
</pre>
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