<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/148258>148258</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [flang] Unexpected runtime failure when allocating a zero-sized array
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            flang:runtime
      </td>
    </tr>

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

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

<pre>
    Consider the following code

```
real, allocatable :: r1(:)
call sub(r1, [real :: ], 0)

contains
subroutine sub(obj, source, size)
real, allocatable :: obj(:)
real :: source(size)
integer :: size

allocate(obj, source=source)
print*, allocated(r1)

end subroutine
end
```

Flang failed at runtime with
```
> a.out

fatal Fortran runtime error(t.f:2): Assign: left-hand side variable is neither allocated nor allocatable
IOT/Abort trap(coredump)
```

Flang supports allocating zero-sized array as shown in issue #148255, this variation should also be supported.
</pre>
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