On Apr 4, 2011, at 12:38 PM, Bing Li <[email protected]> wrote: > if (nil == defaultMenu) > { > @synchronized(self) > { > if (nil == defaultMenu)
Don't do this. I don't mean just in Cocoa either, I mean don't do it ever. It's an anti-pattern called "double-checked locking" and it's fatally broken under most languages' memory models. If you want to initialize a value once-and-only-once, use dispatch_once or (if you need to support an OS version without GCD) use pthread_once. -- Chris _______________________________________________ Cocoa-dev mailing list ([email protected]) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [email protected]
