>
> Do you understand why -funroll-loops causes the code to fail to work?
> Because I cannot.  Unless I'm missing something, this sounds like a
> GCC bug.
>

I've no idea. For that we would have to look into generated assembly code,
but I'd rather leave that for compiler professionals to analyze. Would
forward it to GCC guys?

And how about filtering this flag for good as I asked earlier?

CFLAGS := $(filter-out -funroll-loops,$(CFLAGS))