Aloha, I just tried to build Boost 1.34.1 fat (a.k.a. Universal) libraries for MacOS X. This is what happened: I created the following ~/user-config.jam file in order to build Universal libs: using darwin : # version : # command not specified ? use default : # options <compileflags>"-O -g -isysroot /Developer/SDKs/MacOSX10.4u.sdk - arch i386 -arch ppc" <linkflags>"-arch i386 -arch ppc" ; As described in http://www.boost.org/more/getting_started/unix- variants.html 5.1 "Easy Build and Install" I tried to fire up the build system like this: macpro01:/Volumes/Macintosh HD 2/boost_1_34_1 $ ./configure --prefix=/ usr/local/ Building Boost.Jam with toolset darwin... ./configure: line 198: cd: / Volumes/Macintosh: No such file or directory ./configure: line 1: cd: ./tools/jam/src: No such file or directory tools/jam/src//bjam Detecting Python version... 2.5 Detecting Python root... /sw Unicode/ICU support for Boost.Regex?... not found. Backing up existing Boost.Build configuration in user-config.jam.2 Generating Boost.Build configuration in user-config.jam... Generating Makefile... It seems that configure has a problem with "Macintosh HD 2" as a directory name... $ make make: *** No targets specified and no makefile found. Stop. WHATEVER - there's still the 5.2 "custom" way to build the boost libs: $ cd ~/boost_1_34_1/tools/jam/src $ ./build.sh $ cp bin.macosxx86/bjam ../../../ $ cd ~/boost_1_34_1/ $ ./bjam --prefix=/usr/local $ sudo ./bjam install ... 1 hour later everything _seems_ to be fine: $ file /usr/local/lib/libboost_filesystem-1_34_1.dylib /usr/local/lib/libboost_filesystem-1_34_1.dylib: Mach-O universal binary with 2 architectures /usr/local/lib/libboost_filesystem-1_34_1.dylib (for architecture i386): Mach-O dynamically linked shared library i386 /usr/local/lib/libboost_filesystem-1_34_1.dylib (for architecture ppc): Mach-O dynamically linked shared library ppc That's exactly what I wanted. But... THIS is really strange (test.cpp is the regex example from the install manual): $ g++ test.cpp -I/usr/local/include/boost-1_34_1/ -L/usr/local/lib/ - lboost_regex-mt-d-1_34_1 $ ./a.out dyld: Library not loaded: /var/tmp//ccMlDtbZ.out Referenced from: /Volumes/Macintosh HD 2/./a.out Reason: image not found Trace/BPT trap WHAT? I _never_ referenced a library called /var/tmp//ccMlDtbZ.out. What's going on here? Any help is GREATLY appreciated! Thanks, Ole