Specify compiler in setup

paddle/setup.py.in

@@ -55,6 +55,9 @@ elif is_osx == True:
 
 include_dirs = [np.get_include(), "../"]    # include numpy and paddle.
 
+os.environ["CC"] = "@CMAKE_C_COMPILER@"
+os.environ["CXX"] = "@CMAKE_CXX_COMPILER@"
+
 setup(name="py_paddle",
   version="@PADDLE_VERSION@",
   ext_modules=[