Folks, I've tried to re-built 1.41 and 1.39 using the suggested patch. The libraries build successfully, but a single test ( "spinlock_try_test" ) for smart_ptr fails. Please, examine the issue and provide with solution or workaround. I've created a ticket on that - https://svn.boost.org/trac/boost/ticket/3678 Alexander Churanov, maintainer of devel/boost-* for FreeBSD