@pinned classes

[bearophile]

Justin Spahr-Summers:
> I think the D2 spec puts restrictions on what you can do with GC-
> allocated pointers (can't convert them to integers, can't perform 
> arithmetic on them outside of their bounds, etc.), and I think they're 
> restrictive enough that a copying garbage collector could work with no 
> changes to compliant code.

Without annotations here the compiler has to find by itself that instances of this class is harder to move:


import std.c.stdio: printf;

class Foo {
    int x;
    int* ptrx;
    this(int xx) {
        this.x = xx;
        this.ptrx = &(this.x);
    }
}
void main() {
    auto f = new Foo(10);
    printf("%d %d\n", f.x, *f.ptrx);
    auto p = f.ptrx;
}

Bye,
bearophile