<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/93845>93845</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Flang] Incorrect diagnose on NULL(mold) being actual arg to `same_type_as` and `extends_type_of`
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            bug,
            flang:frontend
      </td>
    </tr>

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

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

<pre>
    Consider the following code
```
type dt
  real :: r1
end type
logical :: res
type(dt), pointer :: a, b
res = same_type_as(null(a), b)
res = extends_type_of(null(a), b)
end
```

Flang currently issues errors as:
```
./tt.f:6:20: error: A NULL() pointer is not allowed for 'a=' intrinsic argument
  res = same_type_as(null(a), b)
 ^^^^^^^
./tt.f:7:23: error: A NULL() pointer is not allowed for 'a=' intrinsic argument
  res = extends_type_of(null(a), b)
 ^^^^^^^
```

The code seems standard conforming to me. 
`null(a)` returns a disassociated pointer that has the characteristics as `a`. The argument of `same_type_as` and `extends_type_of` requires it does not have an `undefined` association status. `Disassociated` is not `undefined`.
</pre>
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