The Boehm-Demers-Weiser conservative garbage collector can be used as a 
garbage collecting replacement for C malloc or C++ new. It allows you to 
allocate memory basically as you normally would, without explicitly 
deallocating memory that is no longer useful. The collector automatically 
recycles memory when it determines that it can no longer be otherwise 
accessed.

The collector is also used by a number of programming language 
implementations that either use C as intermediate code, want to 
facilitate easier interoperation with C libraries, or just prefer 
the simple collector interface.

libatomic_ops is an optional dependency, but gc will use an internal copy
if it's not already installed on the system.