i cloned the git repository by following command.

i use ubuntu12.10

1) git clone --recursive https://github.com/boostorg/boost.git modular-boost

2) ./bootstrap.sh

3) ./b2 headers

after this on running the following command for separately compiled libraries,

4) ./b2

gcc-4.7/release/link-static/threading-multi/bzip2.o
libs/iostreams/src/bzip2.cpp:20:56: fatal error: bzlib.h: No such file or directory
compilation terminated.

    "g++"  -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread  -DBOOST_ALL_NO_LIB=1 -DBOOST_IOSTREAMS_USE_DEPRECATED -DNDEBUG  -I"." -c -o "bin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi/bzip2.o" "libs/iostreams/src/bzip2.cpp"

...failed gcc.compile.c++ bin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi/bzip2.o...
...skipped <pbin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi>libboost_iostreams.a(clean) for lack of <pbin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi>bzip2.o...
...skipped <pbin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi>libboost_iostreams.a for lack of <pbin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi>bzip2.o...
...skipped <pstage/lib>libboost_iostreams.a for lack of <pbin.v2/libs/iostreams/build/gcc-4.7/release/link-static/threading-multi>libboost_iostreams.a...
gcc.compile.c++ bin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi/bzip2.o
libs/iostreams/src/bzip2.cpp:20:56: fatal error: bzlib.h: No such file or directory
compilation terminated.

    "g++"  -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -fPIC  -DBOOST_ALL_NO_LIB=1 -DBOOST_IOSTREAMS_DYN_LINK=1 -DBOOST_IOSTREAMS_USE_DEPRECATED -DNDEBUG  -I"." -c -o "bin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi/bzip2.o" "libs/iostreams/src/bzip2.cpp"

...failed gcc.compile.c++ bin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi/bzip2.o...
...skipped <pbin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi>libboost_iostreams.so.1.55.0 for lack of <pbin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi>bzip2.o...
...skipped <pstage/lib>libboost_iostreams.so.1.55.0 for lack of <pbin.v2/libs/iostreams/build/gcc-4.7/release/threading-multi>libboost_iostreams.so.1.55.0...
...skipped <pstage/lib>libboost_iostreams.so for lack of <pstage/lib>libboost_iostreams.so.1.55.0...
...failed updating 2 targets...
...skipped 6 targets...

i would appreciate if someone would guide me how to solve the problem.

thank you!