On Jul 17, 2014, at 11:01 PM, Jens Alfke <j...@mooseyard.com> wrote:
> Every once in a while I run into a bug in my code that’s triggered by self > getting dealloced in the middle of a method. It’s usually something like > - (void) someMethod { > doSomeStuff; > [self.delegate object: self didSomeStuff: yeah]; > doSomeMoreStuff; > } > where it turns out that the delegate method clears its reference to me, and > that was the last reference, causing self to get dealloced during the > delegate call, causing doSomeMoreStuff to crash. > > Once I’ve identified such a bug, the fix is easy: put a [[self retain] > autorelease] at the top of the method. Except now I’m using ARC, and I can’t > find a simple way of doing it. I tried adding > __unused id retainedSelf = self; [Conjecture] I haven’t tried it, but maybe the following would work: __unused id retainedSelf __attribute__((objc_precise_lifetime)) = self; Now retainedSelf should be retained until it goes out of scope. But I don’t know whether the optimizer is still allowed to mess with this. > but the optimizer recognizes that retainedSelf isn’t used and strips it out, > making this a no-op. The only thing I’ve found that works is > CFRetain((__bridge CFTypeRef)self); > at the top of the method, and a corresponding CFRelease at the end, but this > is pretty ugly and could cause leaks if the method returns early. > > Am I missing some convenient way of doing this? I looked through the ARC > docs, at least those I could find, and didn’t see anything relating to this. > > —Jens_______________________________________________ > > 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/dave.fernandes%40utoronto.ca > > This email sent to dave.fernan...@utoronto.ca _______________________________________________ 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