Attributes lost in TypeInfo, please advise

[Jakob Ovrum via Digitalmars-d]

Consider the following:

---
struct S
{
     ~this() @safe {}
}

void foo() @safe
{
     S s;
     // OK
}

void bar() @safe
{
     S s;
     destroy(s);
     // test.d(15): Error: safe function 'test.bar' cannot call 
system function 'object.destroy!(S).destroy'
}
---

`destroy` is used in algorithms using low-level operations like 
`emplace[Ref]`, and while `destroy` itself is a template and thus 
enjoys attribute inference, it calls the non-generic 
typeid(T).destroy function, which is unconditionally @system. 
This unsafety then propagates all the way up to high-level code 
that is otherwise inferred to be safe.

The `postblit` TypeInfo method, used from `emplace[Ref]`, has the 
same problem.

Is it possible to call the destructor or postblit constructor 
directly, and will they correctly destruct/copy recursively like 
TypeInfo.destroy/postblit do? If so, we should change `destroy` 
and `emplaceImpl` to use direct calls ASAP.