Hey Tim,
The lockfree::queue constructors raise a static assert if no capacity is specified. This contradicts the member initialization code close to the assert, for instance:
queue(void): head_(tagged_node_handle(0, 0)), tail_(tagged_node_handle(0, 0)), pool(node_allocator(), has_capacity ? capacity : 0) { BOOST_STATIC_ASSERT(has_capacity); initialize(); }
which implies that 'has_capacity' is allowed to be false. From what I can see 'has_capacity' could be false, indeed, in particular if the queue is not bounded in size.
the idea is that the default constructor is only allowed, when the capacity is set at compile-time. otherwise the data structure won't be completely lockfree, as creating new nodes will hit the memory allocator. so the assertion is correct, but the initialization of the pool can be changed.
Hmmm, I do not understand. If the queue is constructed with fixed_size<false> (which is the default), this assertion will _always_ fire as you're not required to specify a capacity in this case. Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu