Re: alloc init thread safe?
Re: alloc init thread safe?
- Subject: Re: alloc init thread safe?
- From: Rosyna <email@hidden>
- Date: Thu, 8 Mar 2007 18:44:30 -0700
The first message to a Class is *not* threadsafe when ZeroLink is on.
This is why the problem disappears in Release mode, because ZeroLink
is always off in Release mode.
Everyone on this list should immediately do this in Xcode:
Switch to Debug/Development mode, go to the Build menu and make sure
Allow ZeroLink is UNCHECKED.
ZeroLink offers no real benefits (especially to typical Cocoa
developers that work with a relatively small number of files). And it
causes random problems to appear like this one.
ZeroLink should always be off. It should never be turned on.
Ack, at 3/7/07, email@hidden said:
I have one object of Class1. This object has a method
- (id) C2_alloc_init {
return [[Class2 alloc] init];
}
This method can be called from multiple threads simultaneously.
Sometimes this would return null, and it appears from the trace
messages that this occurs when it is being called from two threads
at about the same time. Both classes are subclasses of NSObject.
The problem seems to be solved by putting a lock around the alloc
init calls, doing an unlock before returning the value.
So did I miss some documentation that says alloc init are not thread
safe? Or at least alloc?
--
Sincerely,
Rosyna Keller
Technical Support/Carbon troll/Always needs a hug
Unsanity: Unsane Tools for Insanely Great People
It's either this, or imagining Phil Schiller in a thong.
_______________________________________________
Cocoa-dev mailing list (email@hidden)
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:
This email sent to email@hidden