Re: GSAutoreleasedMemory

[Richard Frith-Macdonald]

On 30 Nov 2006, at 16:27, Marc Brünink wrote:

> Richard Frith-Macdonald wrote:
> > On 30 Nov 2006, at 15:21, Marc Brünink wrote:
> >
> > > Hi all,
> > >
> > > thanks to NSDebug I found two small memory leaks. However there's  
> > > another one:
> > > I'm loosing 2 instances of GSAutoreleasedMemory every few runloops.
> > >
> > > I do not understand /usr/src/core/base/Source/Additions/ 
> > > GSObjCRuntime.m at the moment. So could anyone explain me the use  
> > > of GSAutoreleasedMemory please?
> >
> > GSAutoreleasedMemory is a private class whose instances are used  
> > to wrap  an area of memory on the heap which is to be freed when  
> > the enclosing autorelease pool is deallocated.  It should be  
> > impossible for this to be leaked unless you are running without an  
> > autorelease pool... in which case you should get lots of warning  
> > messages.  Are you sure you are not misinterpreting things?
> No. Of course I'm not sure :-)
> However I'm also loosing an autoreleased local NSString. So I've a  
> problem with AutorelasePools. However I do not get any "autorelease  
> called without pool...." message. Perhaps I'm getting an exception  
> in a background thread, which is not caught. In such a case the  
> corresponding pool wouldn't be released. However the thread itself  
> would exit. Could this cause the problem?

If it doesn't exit cleanly, yes.  On clean exit (ie the method the  
thread was launched with returns normally) the thread's autorelease  
pool is deallocated and all memory should be cleaned up ... assuming  
no bugs.  If the thread exits abnormally  ... eg it crashes or calls  
exit() then autoreleased stuff won't get deallocated.