Crash on inserting items in NSTableView?

Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000019001fa4c8
Crashed Thread: 0 Dispatch queue: com.apple.main-thread

Thread 0 Crashed: Dispatch queue: com.apple.main-thread
0 libSystem.B.dylib 0x00007fffffe007c5 __memcpy + 37
1 com.apple.AppKit 0x00007fff85e5ea7c _NSLayoutTreeSetLocationForGlyphRange + 1122
2 com.apple.AppKit 0x00007fff85e5dfe6 -[NSATSLineFragment saveWithGlyphOrigin:] + 3725
3 com.apple.AppKit 0x00007fff85dc5996 -[NSATSTypesetter _layoutLineFragmentStartingWithGlyphAtIndex:characterIndex:atPoint:renderingContext:] + 7239
4 com.apple.AppKit 0x00007fff85e59373 -[NSATSTypesetter layoutParagraphAtPoint:] + 204
5 com.apple.AppKit 0x00007fff862fedae -[NSTypesetter _layoutGlyphsInLayoutManager:startingAtGlyphIndex:maxNumberOfLineFragments:maxCharacterIndex:nextGlyphIndex:nextCharacterIndex:] + 2637
6 com.apple.AppKit 0x00007fff85e58b22 -[NSTypesetter layoutCharactersInRange:forLayoutManager:maximumNumberOfLineFragments:] + 210
7 com.apple.AppKit 0x00007fff85e58a0b -[NSATSTypesetter layoutCharactersInRange:forLayoutManager:maximumNumberOfLineFragments:] + 1238
8 com.apple.AppKit 0x00007fff85e56fe8 -[NSLayoutManager(NSPrivate) _fillLayoutHoleForCharacterRange:desiredNumberOfLines:isSoft:] + 1131
9 com.apple.AppKit 0x00007fff85e569b0 -[NSLayoutManager(NSPrivate) _fillLayoutHoleAtIndex:desiredNumberOfLines:] + 211
10 com.apple.AppKit 0x00007fff85e5562f _NSFastFillAllLayoutHolesUpToEndOfContainerForGlyphIndex + 679
11 com.apple.AppKit 0x00007fff85e551a5 -[NSLayoutManager textContainerForGlyphAtIndex:effectiveRange:] + 243
12 com.apple.AppKit 0x00007fff85d6ac12 -[NSLayoutManager glyphRangeForTextContainer:] + 286
13 com.apple.AppKit 0x00007fff85ebcbb9 -[NSStringDrawingTextStorage drawTextContainer:withRect:graphicsContext:baselineMode:scrollableadding:] + 370
14 com.apple.AppKit 0x00007fff85e08034 _NSStringDrawingCore + 4399
15 com.apple.AppKit 0x00007fff85e06cf3 _NSDrawTextCell + 3117
16 com.apple.AppKit 0x00007fff85e0e9fc -[NSTableView drawRow:clipRect:] + 1242
17 com.apple.AppKit 0x00007fff85e0e2ef -[NSTableView drawRowIndexes:clipRect:] + 369
18 com.apple.AppKit 0x00007fff85e0cc9c -[NSTableView drawRect:] + 1302
19 com.apple.AppKit 0x00007fff85e02cc5 -[NSView _drawRect:clip:] + 3390
20 com.apple.AppKit 0x00007fff85e01938 -[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 1325
21 com.apple.AppKit 0x00007fff85e01ca2 -[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 2199
22 com.apple.AppKit 0x00007fff85e0000a -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 767
23 com.apple.AppKit 0x00007fff85e00ed6 -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 4555
24 com.apple.AppKit 0x00007fff85e00ed6 -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 4555
25 com.apple.AppKit 0x00007fff85e00ed6 -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 4555
26 com.apple.AppKit 0x00007fff85e00ed6 -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 4555
27 com.apple.AppKit 0x00007fff85e00ed6 -[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 4555
28 com.apple.AppKit 0x00007fff85dffb2c -[NSThemeFrame _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 254
29 com.apple.AppKit 0x00007fff85dfc3de -[NSView _displayRectIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:] + 2683
30 com.apple.AppKit 0x00007fff85d75c0e -[NSView displayIfNeeded] + 969
31 com.apple.AppKit 0x00007fff85d70aba _handleWindowNeedsDisplay + 678
32 com.apple.CoreFoundation 0x00007fff85b6fb07 __CFRunLoopDoObservers + 519
33 com.apple.CoreFoundation 0x00007fff85b4b434 __CFRunLoopRun + 468
34 com.apple.CoreFoundation 0x00007fff85b4ad8f CFRunLoopRunSpecific + 575
35 com.apple.HIToolbox 0x00007fff89fc67ee RunCurrentEventLoopInMode + 333
36 com.apple.HIToolbox 0x00007fff89fc6551 ReceiveNextEventCommon + 148
37 com.apple.HIToolbox 0x00007fff89fc64ac BlockUntilNextEventMatchingListInMode + 59
38 com.apple.AppKit 0x00007fff85d45eb2 _DPSNextEvent + 708
39 com.apple.AppKit 0x00007fff85d45801 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 155
40 com.apple.AppKit 0x00007fff85d0b68f -[NSApplication run] + 395
41 com.apple.AppKit 0x00007fff85d043b0 NSApplicationMain + 364


i dont understand

please guide me..