I appologize if this has been addressed before. I did a quick search of the of the new group and didn't find anything. I just tried to port a code that uses Boost to a new computer loaded with RedHat 7.3. It seems that in 7.3 the /usr/include/asm/atomic.h header is different and generates a warning (i.e. #warning Using kernel header in userland program. BAD! instead of supplying routines like atomic_add and atomin_sub that are apparently required by Boost for the shared_ptr implementation. I ended up replacing this 7.3 header with one from 7.1 and this fixed the problem, but if anyone has a better solution, I would appreciate it. Thanks, Scott -- ===================================================================== Dr. Scott Collis, Asst. Prof. | Tel: (713) 348-3617 Dept. of Mechanical Engineering | Fax: (713) 348-5423 and Materials Science - MS 321 | Rice University | Email: collis@rice.edu Houston, TX 77005-1892 | http://mems.rice.edu/~collis =====================================================================