Hello, I cannot compile boost with clang 3.1 on Mac os x 10.8.2. This is what I did: ./boostrap.sh --with-toolset=clang ./b2 toolset=clang cxxflags="-std=c++11 -stdlib=libc++" linkflags="-stdlib=libc++" I also tried without chrono, test, wave and signals. I tried a user-config.jam with using clang-darwin This is the error I have for almost every file: /boost/config/select_stdlib_config.hpp:18:12: fatal error: 'cstddef' file not found It is kind of similar to [ http://stackoverflow.com/questions/8486077/how-to-compile-link-boost-with-clang-libc][1 ] I do have the latest Xcode 4.5.2 with the command line tools installed. Here is part of the console output: Kikohs:trunk kikohs$ ./b2 toolset=clang cxxflags="-std=c++11 -stdlib=libc++" linkflags="-stdlib=libc++" Performing configuration checks - 32-bit : no - 64-bit : yes - x86 : yes - has_icu builds : no warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam - gcc visibility : yes - long double support : no warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. Building the Boost C++ Libraries. - iconv (libc) : no - iconv (separate) : yes - icu : no - icu (lib64) : no Component configuration: - atomic : building - chrono : building - context : building - date_time : building - exception : building - filesystem : building - graph : building - graph_parallel : building - iostreams : building - locale : building - math : building - mpi : building - program_options : building - python : building - random : building - regex : building - serialization : building - signals : building - system : building - test : building - thread : building - timer : building - wave : building ...patience... ...patience... ...patience... ...patience... ...found 8672 targets... ...updating 1127 targets... common.mkdir bin.v2/libs/atomic common.mkdir bin.v2/libs/atomic/build common.mkdir bin.v2/libs/atomic/build/clang-darwin-4.2.1 common.mkdir bin.v2/libs/atomic/build/clang-darwin-4.2.1/debug clang-darwin.compile.c++ bin.v2/libs/atomic/build/clang-darwin-4.2.1/debug/lockpool.o In file included from libs/atomic/src/lockpool.cpp:1: ./boost/atomic.hpp:10:10: fatal error: 'cstddef' file not found #include <cstddef> ^ 1 error generated. "clang++" -x c++ -O0 -g -std=c++11 -stdlib=libc++ -O0 -fno-inline -Wall -g -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_ATOMIC_SOURCE -I"." -c -o "bin.v2/libs/atomic/build/clang-darwin-4.2.1/debug/lockpool.o" "libs/atomic/src/lockpool.cpp" Any help would be greatly appreciated, Thank you, Kikohs