Trouble building on OS X 10.10.4

Hi there, I am having trouble building latest version of gr-osmosdr on my Mac. I am having identical issue with homebrew version (from chleggett tap) as with cloning from http://git.osmocom.org/gr-osmosdr/. `make` step always fails with linker error Undefined symbols for architecture x86_64: "_rtlsdr_get_index_by_serial", referenced from: rtl_source_c::rtl_source_c(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in rtl_source_c.cc.o "_rtlsdr_set_agc_mode", referenced from: rtl_source_c::rtl_source_c(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in rtl_source_c.cc.o rtl_source_c::set_gain_mode(bool, unsigned long) in rtl_source_c.cc.o non-virtual thunk to rtl_source_c::set_gain_mode(bool, unsigned long) in rtl_source_c.cc.o "_rtlsdr_set_direct_sampling", referenced from: rtl_source_c::rtl_source_c(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in rtl_source_c.cc.o "_rtlsdr_set_offset_tuning", referenced from: rtl_source_c::rtl_source_c(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in rtl_source_c.cc.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) make[2]: *** [lib/libgnuradio-osmosdr.0.1.5git.dylib] Error 1 make[1]: *** [lib/CMakeFiles/gnuradio-osmosdr.dir/all] Error 2 make: *** [all] Error 2 Trying to add -DCMAKE_CXX_FLAGS=-libstd=libstdc++ only results in even more undefined symbols on top of these. I'm not sure where to proceed from here. This is my first post to this list, so hello everyone! and Thanks for any help. Nils