Steps followed:

git clone git://git.osmocom.org/gr-osmosdr (commit 86ad584204762eeb01f07daa683673f1ec3f1df5)
cd gr-osmosdr/
mkdir build
cd build/
ENABLE_FCD=ON ENABLE_FCDPP=ON cmake ../
make
Scanning dependencies of target gnuradio-osmosdr
[ 10%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/source_impl.cc.o
[ 20%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/sink_impl.cc.o
[ 30%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/ranges.cc.o
[ 40%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/device.cc.o
[ 50%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/time_spec.cc.o
[ 60%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/fcd/fcd_source_c.cc.o
[ 70%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/file/file_source_c.cc.o
[ 80%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/rtl_tcp/rtl_tcp_source_f.cc.o
[ 90%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/rtl_tcp/rtl_tcp_source_c.cc.o
[100%] Building CXX object lib/CMakeFiles/gnuradio-osmosdr.dir/rfspace/rfspace_source_c.cc.o
make[2]: *** No rule to make target `/usr/lib64/lib64/libboost_thread-mt.so.5', needed by `lib/libgnuradio-osmosdr-0.1.5git.so.0.0.0'.  Stop.
make[1]: *** [lib/CMakeFiles/gnuradio-osmosdr.dir/all] Error 2
make: *** [all] Error 2

I wonder if anyone can help me with this? Looks like the path to libboost_thread-mt.so.5 has two lib64s in it.

I'm running CentOS 6.6.