It looks like your copy of libunittest++.a
was compiled with a different implementation of the standard C++ library. On OS X there are now two implementations of the standard C++ library: GNU's libstdc++, whose header files reside in /usr/include/c++/4.2.1
and Clang's libc++, whose header files are in /usr/lib/c++/v1/
.
Your copy of libunittest++.a
appears to have been compiled with GNU's libstdc++, so you can either fix the issue by using the same library for your program:
SET(CMAKE_CXX_FLAGS "-stdlib=libstdc++ -std=c++11")
Or re-compile libunittest++.a
with using Clang's libc++.
Also see this question for more helpful information.