Re: GC question

[Han-Wen Nienhuys]

Erik Sandberg wrote:
> class A {
>   SCM b_;
>   A() { b_ = get_b (); scm_gc_protect_object (b_); }
>   ~A() { scm_gc_unprotect_object (b_); }
>   ...
> };
>
> Now if a third smob C contains an A object, as in
>
> class C {
>   A a_;
>   ...
>   DECLARE_SMOBS (C);
> };
>
> .. then A's gc_unprotect will be called during the gc sweep.
>
> Is my problem related to the smob macros in Lilypond? (if not, I should ask on 
> guile-user instead).

do the following:

  make A::protect() and A::unprotect().

In C::C call A::unprotect, and use C::mark to mark the smob. You will 
also need machinery to make sure unprotect() isn't called if the B is no 
longer protected.

--
 Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwen