Make Mac OS X target require 64bit (to support modern Objective-C runtime, namely ivars in class extensions)
Make Mac OS X target require 64bit (to support modern Objective-C runtime,
namely ivars in class extensions)

sanojnambiar/libextobjc,kolyuchiy/libextobjc,goodheart/libextobjc,bboyesc/libextobjc,sunfei/libextobjc,telly/libextobjc,WPDreamMelody/libextobjc,sandyway/libextobjc,liuruxian/libextobjc,KBvsMJ/libextobjc,jiakai-lian/libextobjc