Hi Boost-ers, I am trying to create a boost::unordered_map in a boost::interprocess::managed_shared_memory segment. This works fine until I try to change from using boost::interprocess::allocator to boost::interprocess::cached_node_allocator. It seems that the hash_bucket structure is deferring the key size calculation, but the cached_node_allocator needs the size at compilation time. Any ideas on how to make this work? Below is a sample attempt which displays my problem along with the GCC output. Thanks, -Lenny Sample code: #include <boost/interprocess/managed_shared_memory.hpp> #include <boost/interprocess/segment_manager.hpp> #include <boost/interprocess/containers/string.hpp> #include <boost/interprocess/allocators/cached_node_allocator.hpp> #include <boost/unordered_map.hpp> using namespace boost::interprocess; int main () { //Create shared memory. managed_shared_memory segment(create_only, "SharedMem", //segment name 65536); // Define cached node allocator type for char in a shared memory segment. typedef boost::interprocess:: cached_node_allocator<char, managed_shared_memory::segment_manager> cached_node_allocator_t; // Define an interprocess string type which uses the cached node allocator. typedef boost::interprocess:: basic_string<char, std::char_traits<char>, cached_node_allocator_t> shared_string_t; // Get an instance of the allocator. cached_node_allocator_t allocator_instance( segment.get_segment_manager()); // Create an unordered map with Key and Value as interprocess strings, using the default hash and predicate // and use the cached node allocator. boost::unordered_map<shared_string_t, shared_string_t, boost::hash<shared_string_t>, std::equal_to<shared_string_t>, cached_node_allocator_t> my_map_t(allocator_instance); return 0; } GCC output: $ g++ -I/opt/local/include cnasum.cc /opt/local/include/boost/interprocess/allocators/detail/allocator_common.hpp: In instantiation of ‘const size_t boost::interprocess::sizeof_value<boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >::value’: /opt/local/include/boost/interprocess/allocators/cached_node_allocator.hpp:104: instantiated from ‘boost::interprocess::cached_node_allocator<boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>’ /opt/local/include/boost/unordered/detail/fwd.hpp:134: instantiated from ‘boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ /opt/local/include/boost/unordered/detail/fwd.hpp:278: instantiated from ‘boost::unordered_detail::hash_iterator_base<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/fwd.hpp:347: instantiated from ‘boost::unordered_detail::hash_buckets<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/fwd.hpp:921: instantiated from ‘boost::unordered_detail::types<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::map_extractor<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > > >, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/unique.hpp:125: instantiated from ‘boost::unordered_detail::map<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ /opt/local/include/boost/unordered/unordered_map.hpp:63: instantiated from ‘boost::unordered_map<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ cnasum.cc:35: instantiated from here /opt/local/include/boost/interprocess/allocators/detail/allocator_common.hpp:43: error: invalid application of ‘sizeof’ to incomplete type ‘boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ $