Non-compatible safety conversion (like C++), prevent void * to T *

[pabuhr]

forall( otype T ) T * realloc( T *ptr, size_t n ) {
    return (T *)(void *)realloc( ptr, sizeof(T) );
}
int fred() {
    int *i;
    double *d;
    // need to change CFA so that T *p = void *p disallowed
    i = realloc( d, 2 );
}

[a3moss]

I think this is one for the new resolver...

...of course, I haven't added generic/pointer types to the prototype yet.

[Rob Schluntz <rschlunt@…>]

In cdbfab0:

Remove unsafe void * constructors and assignment operators from prelude [closes #24] [fixes #51]