How to compile multi-threaded program under buildroot

Hi, All ADI's experts

      I'm in learning dual-core communications between Core A and Core B on bf609-EZboard. I want to use multi-thread in linux, but I don't know how to compile muti-threaded program under buildroot. I checked the (blackfin-buildroot/output/build/libmcapi-10834/libmcapi-2.0/tests),but I  am still don't know how to modify the to connect -lpthread ?

     Hope you apply! thank you!