A header for bridging between ARC and non-ARC code, I.E., 32- vs. 64-bit OS X.

ARCBridge.h

#ifndef PPMacho_ARCBridge_h
#define PPMacho_ARCBridge_h
#include <AvailabilityMacros.h>

#if __has_feature(objc_arc)

#define SUPERDEALLOC
#define RELEASEOBJ(obj)
#define RETAINOBJ(obj) obj
#define RETAINOBJNORETURN(obj)
#define AUTORELEASEOBJ(obj) obj
#define AUTORELEASEOBJNORETURN(obj)
#define BRIDGE(toType, obj) (__bridge toType)(obj)
#define arcstrong strong
#if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_7
#define arcweak weak
#define __arcweak __weak
#else
#define arcweak unsafe_unretained
#define __arcweak __unsafe_unretained
#endif

#else

#define SUPERDEALLOC [super dealloc]
#define RELEASEOBJ(obj) [obj release]
#define RETAINOBJ(obj) [obj retain]
#define RETAINOBJNORETURN(obj) [obj retain]
#define AUTORELEASEOBJ(obj) [obj autorelease]
#define AUTORELEASEOBJNORETURN(obj) [obj autorelease]
#define BRIDGE(toType, obj) (toType)obj

#ifdef __OBJC_GC__
#define arcstrong strong
#define arcweak weak
#define __arcweak __weak
#else
#define arcstrong retain
#define arcweak assign
#define __arcweak
#endif

#endif

#define arcretain arcstrong

// Other useful functions for ARC/CoreFoundation data exchange:
// CFBridgingRetain(), CFBridgingRelease()

#endif