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Two users have sent me identical crash logs, they look like this:

Exception: EXC_BAD_ACCESS (0x0001) Codes: KERN_PROTECTION_FAILURE (0x0002) at 0x00000009

Thread 0 Crashed: 0 0x927d11ec HIObject::GetHIObjectFromRef(void) + 0 1 0x927dc138 GetMenuItemSystemAttributes(MenuData, unsigned short, unsigned long, unsigned long) + 0x68 2 0x927e6270 GetMenuItemAttributes(MenuData, unsigned short, unsigned long) + 0x20 3 0x9284b878 SearchCacheEntries(OpaqueCollection, unsigned long, unsigned long, CheckMenuData, MenuResult, MenuData, unsigned long) + 0x88 4 0x92811ec8 SearchCache(OpaqueCollection, bool, CheckMenuData, MenuResult) + 0x144 5 0x9284a008 CheckMenuKeyCache(MenuData, CheckMenuData) + 0x150 6 0x9280c7c4 CheckMenusForKeyEvent(MenuData, CheckMenuData) + 0xcc 7 0x928189b0 IsMenuKeyEvent(MenuData, OpaqueEventRef, unsigned long, MenuData, unsigned short*) + 0x228 8 0x92828a6c IsMenuKeyEvent + 0x8c 9 0x92e71614 _NSGetMenuItemForCommandKeyEvent + 0x94 10 0x92e2e700 _NSHandleCarbonMenuEvent + 0x1f8 11 0x92dd25cc _DPSNextEvent + 0x4d0 12 0x92de8c24 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 0x74 13 0x92dfcf8c -[NSApplication run] + 0x21c 14 0x92eb948c NSApplicationMain + 0x1d0

Both users cannot reproduce 100%, and one says the problem is now gone. I really have no idea what’s wrong, so if anyone has the slightest clue of what might be the problem here, your help would be much appreciated!

I do gather from the crash log that it has to do with the system going through the menus to match a key event with the key equivalents stored for each menu item. But what could be wrong with the menus to make it crash?

I do set myself up as delegate for one menu and supply a submenu on request. The code to construct the menu is rather simple and I do provide either a key (as a string) or the empty string as key equivalent (not nil).

Can you post code? How are you supplying the submenu (i.e. are you retaining it or is it autoreleased?)

I can post code, but I’m not sure which. The code that builds the menu is trivial and I do not create the menu, the system already has a menu created when it calls the menu item delegate, and I just use: addItemWithTitle:action:keyEquivalent: to fill it. I do add submenus for some of my items, these are auto released.

I’d hoped that someone would recognize the stack dump – maybe a bug with OS X and menu delegates or similar? As said, this problem is randomly experienced by two users out of probably thousands.

Later: I’m writing this off as a framework bug. What seems to be the problem is, that the system will use the sub menus from the menu controlled by the delegate *after asking the delegate to update the menu (so the system will use un-retained menu items). If I retain+autorelease each item of the menu before I re-populate it, the crash seems to disappear.*

Well, coding like that is just good practice… Let this be a lesson to you ;)

WHAT? I hope you’re kidding. Should I also start to go through each item in an array and retain+autorelease before I dispose the array?

Congratulations on catching it! Sounds like one of the harder bugs.