Local fixed sized arrays

[Smoke Adams via Digitalmars-d-learn]

I'm in need of a way to create a local array that isn't GC'ed. It 
must be dynamic in the sense of setting the size at compile time 
but it will be used only in scope and only on structs.

function x(int y)
{
    bool[y] arr;

    arr ~= 3;

}

I care about slicing or anything but appending, removal, and 
indexing. I don't even need bounds checking. I don't see a need 
to get locked in to the GC for such simple cases.