Category on NSObject that logs deallocs, useful when tracking down memory leaks

NSObject+LogDealloc.h

#import <Foundation/Foundation.h>

@interface NSObject (LogDealloc)

- (void)logOnDealloc;

@end

NSObject+LogDealloc.m

#import "NSObject+LogDealloc.h"
#import <objc/runtime.h>

static char __logDeallocAssociatedKey__;

@interface LogDealloc : NSObject
@property (strong) NSString* message;
@end

@implementation NSObject (LogDealloc)

- (void)logOnDealloc
{
    if( objc_getAssociatedObject( self, &__logDeallocAssociatedKey__ ) == nil ) {
        LogDealloc* log = [[LogDealloc alloc] init];
        log.message = NSStringFromClass( self.class );
        objc_setAssociatedObject( self, &__logDeallocAssociatedKey__, log, OBJC_ASSOCIATION_RETAIN );
    }
}

@end

@implementation LogDealloc

- (void)dealloc
{
    NSLog( @"dealloc: %@", self.message );
}

@end

how to use it, it seems not work in my arc project~~

Cool trick. I would just mention that associated objects are released after dealloc.