On Nov 9, 2019, at 08:38, Markus Ruggiero <mailinglists@...> wrote:

Way back when I dabbled around with ObjC (that was in 2002!) I created a small app that shows images from disk. About a year ago I upgraded this app to 64bit and ARC. This went well after a bit of flapping on my side because of deprecation warnings and things. But hey, it functioned and I built the app and it ran well. Btw this has been my only atempt at Cocoa programming since, so I am not a guru at all here).

Recently I upgraded from High Sierra to Mojave and my little app still runs - but it crashes somewhere deep inside Cocoa after the (only) window is closed. Why? I do have that crash consistently but it seems not to happen at the same place all the time. It happens to the built app as well as the app running within Xcode under debugger control. Unfortunately I have no idea how to debug this as my window has been closed and removed and only the menu bar should remain, ready to create a new window. There seems nothing of my code to be involved here

I did hear from a colleague that he has apps (not written by himself) that show the exact same behavior: running fine but crashing when the last window is closed. Is this something known? Anyone has an idea what could be the cause and how to prevent it?

Thanks a lot
---markus---

On Nov 10, 2019, at 9:26 AM, Markus Ruggiero <mailinglists@...> wrote:

On 9 Nov 2019, at 15:28, Sandor Szatmari <admin.szatmari.net@...> wrote:

Sounds like you have ‘Release When Closed’ checked in you XIB/NIB for the window. Try unchecking it.

Click the XIB/NIB in your project navigator and hi-light the window in question in the tree of XIB objects.
Go to the attributes inspector and see what the state of this check box is.

If it’s checked try unchecking it.

Thanks, tried it but did not help. The box was checked, tried both ways, same crash.

Sandor

On Nov 9, 2019, at 08:38, Markus Ruggiero <mailinglists@...> wrote:

Way back when I dabbled around with ObjC (that was in 2002!) I created a small app that shows images from disk. About a year ago I upgraded this app to 64bit and ARC. This went well after a bit of flapping on my side because of deprecation warnings and things. But hey, it functioned and I built the app and it ran well. Btw this has been my only atempt at Cocoa programming since, so I am not a guru at all here).

Recently I upgraded from High Sierra to Mojave and my little app still runs - but it crashes somewhere deep inside Cocoa after the (only) window is closed. Why? I do have that crash consistently but it seems not to happen at the same place all the time. It happens to the built app as well as the app running within Xcode under debugger control. Unfortunately I have no idea how to debug this as my window has been closed and removed and only the menu bar should remain, ready to create a new window. There seems nothing of my code to be involved here

I did hear from a colleague that he has apps (not written by himself) that show the exact same behavior: running fine but crashing when the last window is closed. Is this something known? Anyone has an idea what could be the cause and how to prevent it?

Thanks a lot
---markus---

On 10 Nov 2019, at 19:56, Steve Christensen via Groups.Io <punster@...> wrote:

Stack trace of the crash?

On Nov 10, 2019, at 9:26 AM, Markus Ruggiero <mailinglists@...> wrote:

On 9 Nov 2019, at 15:28, Sandor Szatmari <admin.szatmari.net@...> wrote:

Sounds like you have ‘Release When Closed’ checked in you XIB/NIB for the window.  Try unchecking it.

Click the XIB/NIB in your project navigator and hi-light the window in question in the tree of XIB objects.
Go to the attributes inspector and see what the state of this check box is.

If it’s checked try unchecking it.

Thanks, tried it but did not help. The box was checked, tried both ways, same crash.

Sandor

On Nov 9, 2019, at 08:38, Markus Ruggiero <mailinglists@...> wrote:

Way back when I dabbled around with ObjC (that was in 2002!) I created a small app that shows images from disk. About a year ago I upgraded this app to 64bit and ARC. This went well after a bit of flapping on my side because of deprecation warnings and things. But hey, it functioned and I built the app and it ran well. Btw this has been my only atempt at Cocoa programming since, so I am not a guru at all here).

Recently I upgraded from High Sierra to Mojave and my little app still runs - but it crashes somewhere deep inside Cocoa after the (only) window is closed. Why? I do have that crash consistently but it seems not to happen at the same place all the time. It happens to the built app as well as the app running within Xcode under debugger control. Unfortunately I have no idea how to debug this as my window has been closed and removed and only the menu bar should remain, ready to create a new window. There seems nothing of my code to be involved here

I did hear from a colleague that he has apps (not written by himself) that show the exact same behavior: running fine but crashing when the last window is closed. Is this something known? Anyone has an idea what could be the cause and how to prevent it?

Thanks a lot
---markus---

On 23 Nov 2019, at 19:50, Quincey Morris <quinceymorris@...> wrote:

On Nov 22, 2019, at 13:50 , Markus Ruggiero <mailinglists@...> wrote:

Anyway hopefully someone can make some sense of this.

There’s not really enough information here to really solve the problem. The overall “feel” of the crash is a memory management problem related to the various objects used alongside a NSWindow. It is more than possible that you’ve had the problem all along, and you’ve just been unlucky this hasn’t crashed earlier. It’s presumably crashing now because the timing of various parts of app termination changed, and that’s exposing the long-standing bug.

At the top of your backtrace is this:

0   com.apple.AppKit               0x00007fff3c3cbbd6 -[NSWindow(NSFullScreen) _didExitFullScreen] + 48

My guess is that AppKit is about to invoke the corresponding window delegate method:

    https://developer.apple.com/documentation/appkit/nswindowdelegate/1419146-windowdidexitfullscreen

but your window delegate (probably a NSWindowController) has already been deallocated.

This sort of thing is really hard to debug and fix. The easiest thing to try is to make sure your window controller sets its window’s “delegate” property to nil before it deallocates. If you’re lucky, that will solve it. If not, that might just push the crash to a different place.

On Nov 9, 2019, at 7:37 AM, Markus Ruggiero <mailinglists@...> wrote:

Way back when I dabbled around with ObjC (that was in 2002!) I created a small app that shows images from disk. About a year ago I upgraded this app to 64bit and ARC. This went well after a bit of flapping on my side because of deprecation warnings and things. But hey, it functioned and I built the app and it ran well. Btw this has been my only atempt at Cocoa programming since, so I am not a guru at all here).

Recently I upgraded from High Sierra to Mojave and my little app still runs - but it crashes somewhere deep inside Cocoa after the (only) window is closed. Why? I do have that crash consistently but it seems not to happen at the same place all the time. It happens to the built app as well as the app running within Xcode under debugger control. Unfortunately I have no idea how to debug this as my window has been closed and removed and only the menu bar should remain, ready to create a new window. There seems nothing of my code to be involved here

I did hear from a colleague that he has apps (not written by himself) that show the exact same behavior: running fine but crashing when the last window is closed. Is this something known? Anyone has an idea what could be the cause and how to prevent it?

Thanks a lot
---markus---