Fix various gcc warnings.

source/blender/python/api2_2x/Object.c

@@ -3747,18 +3747,15 @@ static int Object_setAttr( BPy_Object * obj, char *name, PyObject * value )
 	if( StringEqual( name, "dupliGroup" ) ) {
 		PyObject *pyob=NULL;
 		BPy_Group *pygrp=NULL;
-		Group *group;
 		if( !PyArg_Parse( value, "O", &pyob) )
-			return ( EXPP_ReturnPyObjError( PyExc_TypeError,
-							"expected a group" ) );	
+			return EXPP_ReturnIntError( PyExc_TypeError,
+							"expected a group" );	
 		if (pyob==Py_None) {
 			object->dup_group= NULL;
 		} else {
 			pygrp= (BPy_Group *)pyob;
 			object->dup_group= pygrp->group;
 		}
-		
-		
 		return 0;
 	}
 

source/blender/python/api2_2x/Sys.c

@@ -386,7 +386,6 @@ static PyObject *M_sys_sleep( PyObject * self, PyObject * args )
 
 static PyObject *M_sys_exists( PyObject * self, PyObject * args )
 {
-	struct stat st;
 	char *fname = NULL;
 	int mode = 0, i = -1;
 

source/blender/python/api2_2x/sceneRender.c

@@ -1530,6 +1530,7 @@ PyObject *RenderData_EnableCropping( BPy_RenderData * self, PyObject * args )
 				      &self->renderContext->mode );
 */
 	printf("cropping option is now default, obsolete\n");
+	Py_RETURN_NONE;
 }
 
 //------------------------------------RenderData.SetImageType() ---------