NSXMLParser memory leak on ios 4.0 - **NOT** NSCFS

问题:

I'm getting a weird leak in my NSXMLParser after it's done and released from memory.

It comes up with NSMapTable alloc leak. Here's my stack:

   0 libSystem.B.dylib calloc
   1 libobjc.A.dylib _internal_class_createInstanceFromZone
   2 libobjc.A.dylib class_createInstance
   3 Foundation NSAllocateObject
   4 Foundation +[NSMapTable alloc] <===== this is the leak...
   5 Foundation -[NSXMLParser initWithData:]
   6 Foundation -[NSXMLParser initWithContentsOfURL:]
   7 idispatch -[RootViewController parseXML:] /Developer/iPhone  Apps/iDispatch/Classes/RootViewController.m:562 <================== this is my code calling
   8 Foundation -[NSThread main]
   9 Foundation __NSThread__main__
  10 libSystem.B.dylib _pthread_start
  11 libSystem.B.dylib thread_start

Ideas?

Appreciate any light you can shed!

Here's the code:

[NSThread detachNewThreadSelector:@selector(parseXML:) 
                         toTarget:self 
                       withObject:requestStr];

which calls this method on its own thread:

- (void)parseXML:(NSString*)theURL {
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:[NSURL URLWithString:theURL]];
    DLog(@"URL: %@",theURL);
    [parser setDelegate:self];

    [parser parse];

    [parser release];

    [pool release];
    DLog(@"xml parser thread end and released");
}

回答1:

It's perhaps too late but I found this solution :

NSData * dataXml = [[NSData alloc] initWithContentsOfURL:url];
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:dataXml];
[dataXml release];

instead of

NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:url];

No more mem leaks...

回答2:

You should reset the delegate before releasing ([parser setDelegate:nil])

回答3:

Same problem here. The leak appears even if I'm just to this:

NSURL *xmlURL = [NSURL fileURLWithPath:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"myfile.xml"]]; 
NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:xmlURL];
[parser release];

I've reported the bug to apple, since it seems a serious bug in the NSXMLParser class.

回答4:

I have the same problem, Malloc 512 Bytes & NSConcreteMapTable Leaks... also this code does not leak if compiled against Snow Leopard 10.6

I can also confirm that the following code works for ios & mac os without leaks.

        NSData * dataXml = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:query]];
    NSXMLParser *parser = [[NSXMLParser alloc] initWithData:dataXml];
    [parser setDelegate:self];
    [dataXml release];
    [parser parse];
    [parser autorelease];