I'm getting a segfault in Boost when I go to use mutexes. I built the Boost unit test for threads with the following: bjam "-sTOOLS=gcc" "-sBUILD debug <runtime-link>static <threading>multi" In Boost 1.32 there are errors with text_mutex_lib: root@unstable:~/scratch/boost_1_32_0/bin/boost/libs/thread/test/test_mutex_lib.test/gcc/debug/runtime-link-static/threading-multi> ./test_mutex_lib Running 6 test cases... Exception in "test_try_mutex": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_try_mutex": Testing aborted Exception in "test_recursive_mutex": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_recursive_mutex": Testing aborted Exception in "test_recursive_try_mutex": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_recursive_try_mutex": Testing aborted Exception in "test_recursive_timed_mutex": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_recursive_timed_mutex": Testing aborted *** errors detected in test suite "Boost.Threads: mutex test suite"; see standard output for details [---] In Boost 1.32 there are errors with test_xtime_lib: root@unstable:~/scratch/boost_1_32_0/bin/boost/libs/thread/test/test_xtime_lib.test/gcc/debug/runtime-link-static/threading-multi> ./test_xtime_lib Running 2 test cases... Exception in "test_xtime_cmp": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_xtime_cmp": Testing aborted Exception in "test_xtime_get": signal: memory access violation /root/scratch/boost_1_32_0/libs/test/build/../src/unit_test_suite.cpp(150): fatal error in "test_xtime_get": Testing aborted *** errors detected in test suite "Boost.Threads: xtime test suite"; see standard output for details Segmentation fault [---] In Boost 1.33 there are errors with test_mutex_lib: root@unstable:~/scratch/boost_1_33_0/bin/boost/libs/thread/test/test_mutex_lib.test/gcc/debug/runtime-link-static/threading-multi> ./test_mutex_lib Running 6 test cases... unknown location(0): fatal error in "test_try_mutex": signal: memory access violation *** errors detected in test suite "Boost.Threads: mutex test suite"; see standard output for details [--] In Boost 1.33 there are no errors with test_xtime_lib: root@unstable:~/scratch/boost_1_33_0/bin/boost/libs/thread/test/test_xtime_lib.test/gcc/debug/runtime-link-static/threading-multi> ./test_xtime_lib Running 2 test cases... *** No errors detected Well then, i'm thoroughly confused. It seems the unit test Boost has are making calls to libthreaddb.so (NPTL). Anyone have any ideas? I've reproduced this on 2 machines (opterons 246), 2 distros now. What really boggles me is that the one xtime test works on 1.33 but the mutex test doesn't. Simple mutex calls work fine however. Are these specific problems with the test or something deeper? I've seen no discussion on the mailing list.