Garbage collection Libraries in C++ [closed]

What free and commercial garbage collection libraries are available for C++, and what are the pros and cons of each?

I am interested in hard-won lessons from actual use in the field, not marketing or promotional blurb.

There is no need to elaborate on the usual trade offs associated with automatic garbage collection, but please do mention the algorithms used (reference counting, mark and sweep, incremental, etc.) and briefly summarise the consequences.

Solution 1:

I have used the Boehm collector in the past with good success. It's open source and can be used in commercial software.

It's a conservative collector, and has a long history of development by one of the foremost researchers in garbage collection technology.

Solution 2:

Boost has a great range of smart pointers which impliment reference counting or delete-on-scope exit or intrusive reference counting. These have proven enough for our needs. A big plus is that it is all free, open source, templated C++. because it is reference counting, in most cases it is highly deterministic when an object gets destroyed.

Solution 3:

I use boehm-gc a lot. It is straight-forward to use, but the documentation is really poor. There is a C++ page, but its quite hard to find.

Basically, you just make sure that every class inherits from their base class, and that you always pass gc_allocator to a container. In a number of cases you want to use libgccpp to catch other uses of new and delete. These are largely high-level changes, and we find that we can turn off the GC at compile-time using an #ifdef, and that supporting this only affects one or two files.

My major problem with it is that you can no longer use Valgrind, unless you turn the collector off first. While turning the collector off is easy to do, and doesn't require recompiling, it's obviously impossible to use it if you start to run out of memory.