Re: Segfault when NSTextView is released

[Lundberg, Johannes]

Thanks Matt! 

I actually didn't know there are some classes that still do not support weak reference in Cocoa. But does that imply that they also do not support strong reference? If Yes, than I'm totally OK with it and will just use assign property or __unsafe_unretained ivar.

Perhaps we should add the tags you mention to the classes in GNUstep that do not support weak references, like Apple has.

Found this: (https://developer.apple.com/library/mac/releasenotes/ObjectiveC/RN-TransitioningToARC/Introduction/Introduction.html)

Which classes don’t support weak references?

You cannot currently create weak references to instances of the following classes:

NSATSTypesetter, NSColorSpace, NSFont, NSMenuView, NSParagraphStyle, NSSimpleHorizontalTypesetter, and NSTextView.

Note: In addition, in OS X v10.7, you cannot create weak references to instances of NSFontManager, NSFontPanel, NSImage, NSTableCellView, NSViewController, NSWindow, and NSWindowController. In addition, in OS X v10.7 no classes in the AV Foundation framework support weak references.

For declared properties, you should use assign instead of weak; for variables you should use __unsafe_unretained instead of __weak.

In addition, you cannot create weak references from instances of NSHashTable, NSMapTable, or NSPointerArray under ARC.

--

Johannes Lundberg

BRILLIANTSERVICE CO., LTD.

On Sun, Feb 16, 2014 at 4:20 PM, Matt Rice <ratmice@gmail.com> wrote:

On Sat, Feb 15, 2014 at 4:17 PM, Lundberg, Johannes
<johannes@brilliantservice.co.jp> wrote:
>  I don't know if the problem is because my ivar. This should work regardless
> if I store the pointer in an ivar or not. And so far this only occurs on
> NSTextView. I suspect that the way NSTextView releases its objects
> internally is not ARC-friendly.

been a long time since i've been in this area, but I do recall
NSTextView being rather weird due to its support for multiple
ownership graphs, I can definitely see as being non-arc friendly...

looking in our NSTextView.h I didn't see the objc_arc_weak_unavailable
or NS_AUTOMATED_REFCOUNT_WEAK_UNAVAILABLE or a -supportsWeakPointers
which the following indicates should be there

http://stackoverflow.com/questions/12882710/iboutlet-for-nstextview-in-a-arc-project

possibly has something to do with it....

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