2009/8/21 Paolo Bonzini <bonz...@gnu.org>: >> Here tem should not be allocated on GC memory. > > I disagree, as this would not apply to tem only but also to anything > allocated to fold it. This is not going to be maintainable (what if fold > create temporary types, which need to be in GC memory definitely?).
I see. I never investigated what is going on here in detail. If tem were allocated in some obstack, I wouldn't see a problem with allocating its subparts in the obstack too. However I know nothing about those temp types that definitely should be in GC memory. Maybe I will come up with something once I investigate this thoroughly. Maybe this really has to stay as it is. > Not having to deal with the lifetime of "temporary" stuff is part of having > a GC, isn't it? Yes - if you don't know the lifetime or if the lifetime varies. If stuff has a fixed and short lifetime, then I guess non-GC allocation is the best for it. Of course the goal is to have as simple and as maintainable code as possible. Maybe http://gcc.gnu.org/wiki/Memory_management needs some updates. > At most, you may want to add more ggc_free calls, but I don't think this is > necessary either. I agree. Anyway, right now I am not planning to see what can be done about those types that are sometimes allocated in "a proper GC way" and sometimes for scratch only. For the time being, I am working only on those types that are allocated in GC while GC knows nothing about them. -- Laurynas
