std.signals and malloc

[David]

Is there any reason why std.signals.Signal allocates with calloc and
realloc instead of using the gc directly? When digging through the code
everything seems magic and old.

E.g.:
https://github.com/D-Programming-Language/phobos/blob/master/std/signals.d#L199

This looks like an old label used for a goto.

(calloc/realloc:
https://github.com/D-Programming-Language/phobos/blob/master/std/signals.d#L170)

Also rt_detachDisposeEvent and co. are magic to me, I can only guess
what they do when digging through the code, what prevents std.signals
from using the GC. It's just a guess but, I think this would also allow
the use of struct methods as callbacks.

I ran into this issue today:

---
struct Foo {
    Bar bar;

    void my_callback(int i) {
        bar.do_something();
    }
}

slot.connect(&foo.my_callback);
---

This kept segfaulting, chaning Foo to a class solves the issue. (I had
more such strange moments, using curry! together with a helper function
which bound the callbacks also introduced segfaults).

I think that has to do with the manual memory managment used together
with the more or less magic functions.

If you tell me that the manual memory management is an old D1 relict and
isn't needed at all, I could clean that code up and submit a pull
request (I really learned to like std.signals).