On Sat, 17 Mar 2012 15:38:20 -0700, G S <stokest...@gmail.com> said: >I have a member variable to hold an NSDate: > > NSDate* _firstBadAccuracyTime; > >At some point, something happens and I set this value to "now": > > _firstBadAccuracyTime = [NSDate date]; > >On my next trip through this function, I calculate how long it has been >since I set this date: > > NSDate* now = [NSDate date]; > if([now timeIntervalSinceDate:_firstBadAccuracyTime] > >BAD_ACCURACY_TIME) > >then CRASH: BAD ACCESS > >_firstBadAccuracyTime still contains a valid address, but the object >must've been released. Why? If I add a retain where I assign it, the >crash doesn't happen. I added autorelease, but then got a crash on >releasing an object I hadn't allocated (which makes me think it's already >autoreleased). > >Thanks for any insight!
http://www.apeth.com/iOSBook/ch12.html#_memory_management The mistake you're making here is *exactly* the mistake marked with the comment "in non-ARC code this would be a bad idea". Of course ARC relieves you of such worries. And so does passing thru a property with a synthesized accessor, as that chapter goes on to explain. m. -- matt neuburg, phd = m...@tidbits.com, <http://www.apeth.net/matt/> A fool + a tool + an autorelease pool = cool! Programming iOS 5! http://shop.oreilly.com/product/0636920023562.do _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
