Why can't I install Pillow on my mac? It gives

here is the error from installing Pillow. I'm using OS X Mavericks. I tried installing Pillow through pip install..

_imaging.c:391:28: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
                int temp = PyInt_AsLong(op);
                    ~~~~   ^~~~~~~~~~~~~~~~
_imaging.c:397:28: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
                int temp = PyInt_AsLong(op);
                    ~~~~   ^~~~~~~~~~~~~~~~
_imaging.c:407:28: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
                int temp = PyInt_AsLong(op);
                    ~~~~   ^~~~~~~~~~~~~~~~
_imaging.c:413:28: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
                int temp = PyInt_AsLong(op);
                    ~~~~   ^~~~~~~~~~~~~~~~
_imaging.c:520:17: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
            r = PyInt_AsLong(color);
              ~ ^~~~~~~~~~~~~~~~~~~
_imaging.c:533:25: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
                    r = PyInt_AS_LONG(color);
                      ~ ^~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/intobject.h:52:51: note: expanded from macro 'PyInt_AS_LONG'
#define PyInt_AS_LONG(op) (((PyIntObject *)(op))->ob_ival)
                           ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
_imaging.c:561:13: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
        r = PyInt_AsLong(color);
          ~ ^~~~~~~~~~~~~~~~~~~
_imaging.c:575:17: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
            r = PyInt_AsLong(color);
              ~ ^~~~~~~~~~~~~~~~~~~
_imaging.c:969:14: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
        *x = PyInt_AS_LONG(value);
           ~ ^~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/intobject.h:52:51: note: expanded from macro 'PyInt_AS_LONG'
#define PyInt_AS_LONG(op) (((PyIntObject *)(op))->ob_ival)
                           ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
_imaging.c:977:14: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
        *y = PyInt_AS_LONG(value);
           ~ ^~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/intobject.h:52:51: note: expanded from macro 'PyInt_AS_LONG'
#define PyInt_AS_LONG(op) (((PyIntObject *)(op))->ob_ival)
                           ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
_imaging.c:3102:15: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
        y = i / im->xsize;
          ~ ~~^~~~~~~~~~~
12 warnings generated.

The terminal hanged afterwards. The thing is I could try installing it in other ways but I wanna know why it isnt working

UPDATE The thing that has been choking my installation is when I install webp.. It always hangs in there..

I got it.. What I actually did here is installed Pillow through

sudo ARCHFLAGS=-Wno-error=unused-command-line-argument-hard-error-in-future pip install pillow

I realized I had problems with webp and little-cms so I manually installed them through downloading packages..