pragma unroll breaks kernel

Update: I made the steps variable an argument of the kernel so that I can choose not to run the main loop, i.e.

for(long k=0;k<steps;k++){

The output should just be a copy of the input if I set steps=0. However, some array elements are swapped in the output. Somehow the memory load/stores are not working as expected. The strange thing is that the issue only appears if I compile the kernel with the unrolled inner loop (which should never get executed anyway). This seems like a bug to me, but maybe I'm missing something important here.