I am trying to build Boost for G++ 32-bit applications on an Opteron system running Linux Fedora Core 3. This is my command: bjam --user-config=user-config.LINUX_AMD32 threading=multi instruction-set=opteron address-model=32 variant=release,debug,profile --stagedir=stageA32 stage and this is in my user-config file: using gcc : 3.4.4 : /opt/gcc344/bin/g++344 : <compileflags>-fPIC <linkflags>-fPIC ; The first evidence I had is that the .so libraries want to link to 64-bit shared libraries: 12% ldd libboostrgx.so librt.so.1 => /lib64/tls/librt.so.1 (0x00002aaaaac65000) libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x00002aaaaad7f000) libm.so.6 => /lib64/tls/libm.so.6 (0x00002aaaaaf71000) libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00002aaaab0f8000) libpthread.so.0 => /lib64/tls/libpthread.so.0 (0x00002aaaab203000) libc.so.6 => /lib64/tls/libc.so.6 (0x00002aaaab318000) /lib64/ld-linux-x86-64.so.2 (0x0000555555554000) Then I ran the same bjam command with the option that shows the commands executed. This is typical: "/opt/gcc344/bin/g++344" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -fPIC -pthread -march=opteron -DBOOST_ALL_NO_LIB=1 -DNDEBUG -I"." -c -o "bin.v2/libs/test/build/gcc-3.4.4/release/address-model-32/instruction-set-opteron/link-static/threading-multi/test_tools.o" "libs/test/src/test_tools.cpp" It recognized the other options I requested, but not 'address-model=32'. -- Dick Hadsell 914-259-6320 Fax: 914-259-6499 Reply-to: hadsell@blueskystudios.com Blue Sky Studios http://www.blueskystudios.com 44 South Broadway, White Plains, NY 10601