"Responsible Caller" seems arbitrary in Instruments Zombie Allocation Summary View?

I'm wondering if anyone else is seeing this:


it looks to me like the "Responsible caller" value in the allocation summary is misleading, and randomly dropping to stack frames. for example, right now i'm looking at a summary that has these three lines (among others):


Retain -[Solution initWithContentsOfURL:]
Retain -[Solution init]
Release -[Solution init]


seems line 2 and three match, right? think again. if you look at the full stack frames for each, you see this:


   0 Fire -[Solution init] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:0
   1 Fire -[Solution initWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:85
   2 Fire +[Solution solutionWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:664
   3 Fire -[SolutionDocument readFromURL:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.cs:70
   4 Fire -[SolutionDocument readFromURL:ofType:error:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.NSDocument.cs:78
   5 AppKit -[NSDocument _initForURL:withContentsOfURL:ofType:error:]


   0 Fire +[BroadcastManager subscribe:toBroadcast:block:object:] \__windows_drive__c\ci\b\elements\916\source\rtl2\source/broadcasts.swift:107
   1 Fire -[Solution init] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:75
   2 Fire -[Solution initWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:85
   3 Fire +[Solution solutionWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:664
   4 Fire -[SolutionDocument readFromURL:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.cs:70
   5 Fire -[SolutionDocument readFromURL:ofType:error:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.NSDocument.cs:78
   6 AppKit -[NSDocument _initForURL:withContentsOfURL:ofType:error:]


   1 Fire -[Solution init] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:0
   2 Fire -[Solution initWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:85
   3 Fire +[Solution solutionWithContentsOfURL:] /Users/mh/Code/Fire/SharedProjectSystem/Solution.cs:664
   4 Fire -[SolutionDocument readFromURL:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.cs:70
   5 Fire -[SolutionDocument readFromURL:ofType:error:] /Users/mh/Code/Fire/SharedCoreApp/SolutionDocument.NSDocument.cs:78
   6 AppKit -[NSDocument _initForURL:withContentsOfURL:ofType:error:]


turns out, in fact #1 and #3 match up — but the table view is misleading because Instruments decided to drop the top "init" frame from #1 and the top "[BroadcastManager subscribe:toBroadcast:block:object:]" frame from #2.


what's going on here? what logic is Instruments using to determine whether to drop a frame from being "responsible" or not?

"Responsible Caller" seems arbitrary in Instruments Zombie Allocation Summary View?
 
 
Q