Migrating dmd to D?

[jerro]

> Really what is needed is gc arrays and ngc arrays as well as 
> other essential features. e.g., gc arrays would not be part of 
> the core spec while ngc arrays would.

You can already use slices without a gc, like this:

T[] allocate(T)(int n)
{
     return (cast(T*) malloc(T.sizeof * n))[0 .. n];
}

void deallocate(T)(ref T[] a)
{
     free(a.ptr)
     a = null;
}

Of course, you can not append to such slices or expand them 
without a GC. It would be useful to have a @nogc flag which would 
result in an error if a feature that needs a GC was used.

I think adding @nogc would be better than defining a "core spec", 
because most D code does not need that feature. If we add a a 
@nogc flag, the people that don't need it can just ignore its 
existence and do not need to learn about it, but if we call the 
subset of D that doesn't use a GC a "core spec", people will feel 
that's something they need to learn, which will make the language 
seem more complex.