Hi all, The following code seems to generate an "unused variable" variable warning with g++ -Wall. I am working on the latest version available from git, though I am not sure if this version is relevant. #include <boost/lockfree/fifo.hpp> typedef boost::lockfree::fifo<ReplicateData, boost::lockfree::static_freelist_t> Queue; Queue _buffer(4096); It occurs in fifo.hpp at line 263. Replacing tagged_node_ptr head2 = head_.load(memory_order_relaxed); By head_.load(memory_order_relaxed); Seems to do the job. Many thanks, Julien