Leaking NSAutoreleasePool

问题

I'm working on an app and have 1 leak left. The leaked object is NSAutoreleasePool, size is 32 bytes. In the stacktrace only foundation methods are called. I have no clue how to resolve this.

In simulator no leaks reported, on the device only this leak.

Any idea's?

The autoreleasepool is one I define myself.

In my viewcontroller I call:

[self performSelectorInBackground:@selector(getDetailInfo:) withObject:self.infoID];

This is getDetailInfo:

- (void)getDetailInfo:(NSString *)theID {

    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    DetailInfo *info = [[DataProvider sharedInstance] getDetailInfo:theID]; //the return object is autoreleased.
    [self performSelectorOnMainThread:@selector(updateViewWithDetailInfo:) withObject:info waitUntilDone:NO];

    [pool release];
}

Some additional info:

For testing I changed all my methods which were called using performSelectorInBackground to run on the main thread and removed those autoreleasepools.

I still received the leak on the NSAutoreleasePool. Today I learned that you can show the "Library name" in the stacktrace in instruments. :-) I copied it below and you can see the MapKit on line 6 and 7.

0 libSystem.B.dylib calloc
1 libobjc.A.dylib _internal_class_createInstanceFromZone
2 libobjc.A.dylib class_createInstance
3 CoreFoundation +[NSObject(NSObject) allocWithZone:]
4 Foundation +[NSAutoreleasePool allocWithZone:]
5 CoreFoundation +[NSObject(NSObject) alloc]
6 MapKit TileCachePrivate::runCacheThread()
7 MapKit _runCacheThread(void*)
8 libSystem.B.dylib _pthread_start
9 libSystem.B.dylib thread_assign_default

This the code for the mapview:

    MKMapView *omgeving = [[MKMapView alloc] initWithFrame:CGRectMake(11, 22, 298, 297)];
    omgeving.delegate = nil;
    [self addSubview:omgeving];
    [omgeving release];

If I comment out the MapView code, no leak. If I leave it in, I get the Leak.

Leaked Object       #   Address     Size    Responsible Library Responsible Frame
NSAutoreleasePool       0x6a52e50   32      Foundation          +[NSAutoreleasePool allocWithZone:]

Thanks for all the comments so far. Any suggestions?

回答1:

Known issue: https://devforums.apple.com/message/282497#282497

Thanks for thinking along.

回答2:

I have found a leaked NSAutoreleasePool often points at the wrong NSAutoreleasePool. Do you use a NSAutoreleasePool in DataProvider's getDetailInfo? What about the caller?

I've read before that draining an outer NSAutoreleasePool is supposed to drain inner ones, but I haven't found this to be the case.

…Also, drain is preferred over release on NSAutoreleasePool. That isn't your problem, though.

来源：https://stackoverflow.com/questions/4156517/leaking-nsautoreleasepool

标签

iphone

memory-leaks

instruments