COMP: Add -stdlib=libc++ flag for MacOSX

CMakeLists.txt

@@ -57,6 +57,10 @@ else()
   message(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
 endif()
 
+if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
+endif()
+
 #-----------------------------------------------------------------------------
 # Define External dependencies
 #-----------------------------------------------------------------------------