Cannot take slice of scope static array in @safe code

[Dennis via Digitalmars-d-learn]

Compiling the following with -dip1000 gives an error.
```
void main() @safe {
    string[1] a0;
    scope int[1] a1;
    scope string[1] a2;

    scope string[] b0 = a0[]; // Fine
    scope int[] b1 = a1[]; // Fine
    scope string[] b2 = a2[]; // Error: cannot take address of 
scope local a2
}
```

Can anyone explain why? I don't see how b2 violates the scope 
constraint of a2.
It might be a compiler bug, but since the int[] case works, I 
could also just be missing something about how `scope` works on 
`string[1]`.