osx mountain lion - xCode 4.6.3 how to fix autolayout crash in Mac OSX 10.8.4 ( Failed to run one shot request for IBNSLayoutConstraint)? -

i've upgraded osx snow leopard mountain lion , running issue xcode shuts down 100% of time within 5 seconds of opening project. here's error message given. i've tried googling error, cannot find info on subject.

the error appears on opening project, not autolayout ones. message "waiting other symbol copying" appears in status bar on top, xcode crashes exception listed below.

i remember xcode asked me install additional component after osx upgrade, crashed in process of doing , did not ask me again.

i tried re-installing xcode through app store, did not fix issue.

how can fix/repair xcode installation fix error?

process:         xcode [2957] path:            /applications/xcode.app/contents/macos/xcode identifier:      com.apple.dt.xcode version:         4.6.3 (2068) build info:      ideapplication-2068000000000000~3 app item id:     497799835 app external id: 15588541 code type:       x86-64 (native) parent process:  launchd [130] user id:         501  date/time:       2013-07-11 08:14:22.608 -0400 os version:      mac os x 10.8.4 (12e55) report version:  10  interval since last report:          2375 sec crashes since last report:           1 per-app interval since last report:  18 sec per-app crashes since last report:   1 anonymous uuid:                      f0403235-5ecb-adea-6618-e5526b9fe281  crashed thread:  0  dispatch queue: com.apple.main-thread  exception type:  exc_crash (sigabrt) exception codes: 0x0000000000000000, 0x0000000000000000  application specific information: productbuildversion: 4h1503 assertion failure in /sourcecache/ideinterfacebuildercocoatouch/ideinterfacebuildercocoatouch-2083/ibplugin/utilities/ibobjectmarshalling.m:651 details:  failed run 1 shot request ibnslayoutconstraint, ibuiimageview, ibuilabel, ibuitableviewcell, , ibuiview.  interface builder encountered error communicating ios simulator. if choose file crash report or radar issue, please check console.app crash reports "interface builder cocoa touch tool" , include content in crash report.  exception name: ibassertionfailure exception reason: assertion failure: [[self constant] symbolicvalue] || (floor(constantvalue) == constantvalue) reason:     constraint constants should integral (constant attempted set -10.500000). foundation integralize output anyways, if constants not integralized, lead arbitration failures. constraint <ibnslayoutconstraint: 0x8191060> uilabel[0x817b130].center x = uitableviewcell[0x8183690].center x - 10.500000 containingview={<(null):0x0>} scorevector=<0.000000, 3, 1, 1000.000000, 0>, roundingadjustment=0 file:       /sourcecache/ibautolayoutfoundationios/ibautolayoutfoundation-2065/framework/classes/model/constraints/ibnslayoutconstraint.m:460 method:     -[ibnslayoutconstraint assertconstraintvalidity] exception backtrace:    0. corefoundation           0x022ad012 __exceptionpreprocess   1. libobjc.a.dylib          0x0170ce7e objc_exception_throw   2. corefoundation           0x02335fb1 -[nsexception raise]   3. ibautolayoutfoundation   0x0008be44 -[ibnslayoutconstraint assertconstraintvalidity]   4. ibautolayoutfoundation   0x0007b97f -[iblayoutconstraint initwithfirstitem:firstattribute:relation:seconditem:secondattribute:constant:]   5. ibautolayoutfoundation   0x000899d2 -[ibnslayoutconstraint initwithfirstitem:firstattribute:relation:seconditem:secondattribute:constant:]   6. ibautolayoutfoundation   0x0007c1ca -[iblayoutconstraint copywithzone:]   7. ibautolayoutfoundation   0x00089dfe -[ibnslayoutconstraint copywithzone:]   8. libobjc.a.dylib          0x01720ae9 -[nsobject copy]   9. ibautolayoutfoundation   0x0007e0e5 -[iblayoutconstraint constraintbyreplacingview:withview:andreplacingview:withview:]  10. ibautolayoutfoundation   0x000ac46b -[ibautolayoutengine representedconstraintbysubstitutingrealviewsforrepresentedviewsofconstraint:]  11. ibautolayoutfoundation   0x000ac5f6 -[ibautolayoutengine addrepresentedconstraintforrealconstraint:]  12. ibautolayoutfoundation   0x000ae959 -[ibautolayoutengine constraintsmakingsystemoverconstrainedbyaddingconstraint:toview:]  13. ibautolayoutfoundation   0x000b803a +[ibautolayoutarbiter attempttoaddconstraint:bymodifyinglayoutengine:mutuallyexclusiveconstraintbreakagestrategy:mutableconstraintstoadd:mutableconstraintstoremove:]  14. ibautolayoutfoundation   0x000ace27 -[ibautolayoutengine performenginebootstrappingconstraintadditionoperationforaddingconstraint:]  15. ibautolayoutfoundation   0x000ad46e __90-[ibautolayoutengine iterateviewsandgeneraterepresentedconstraintsandmaptorealconstraints]_block_invoke404  16. corefoundation           0x0229acdf __nsdictionaryenumerate  17. corefoundation           0x0229a87d -[nsdictionary enumeratekeysandobjectswithoptions:usingblock:]  18. corefoundation           0x0229a7c5 -[nsdictionary enumeratekeysandobjectsusingblock:]  19. ibautolayoutfoundation   0x000ad150 -[ibautolayoutengine iterateviewsandgeneraterepresentedconstraintsandmaptorealconstraints]  20. ibautolayoutfoundation   0x000a7db9 -[ibautolayoutengine initwitharbitrationunit:options:]  21. ibautolayoutfoundation   0x000c1454 -[ibautolayoutframedecisiondriver initwitharbitrationunit:options:]  22. ???                      0x0000c5a9 [ibcocoatouchtool _startautolayoutframedecisionsessionwithrequest:document:]  23. ???                      0x0000d49c [ibcocoatouchtool runoneshotincrementalframedecisionrequest:withframedecisionsessionrequest:document:]  24. ???                      0x00034fa5 [ibmessagereceivechannel delivermessage:totarget:witharguments:result:]  25. ???                      0x00034cea [ibmessagereceivechannel delivermessage:totarget:witharguments:result:]  26. ???                      0x000349d5 [ibmessagereceivechannel runblockingreceiveloopnotifyingqueue:notifyingtarget:]  27. libdispatch.dylib        0x04c4c731 _dispatch_barrier_sync_f_slow_invoke  28. libdispatch.dylib        0x04c5b014 _dispatch_client_callout  29. libdispatch.dylib        0x04c4b7d5 _dispatch_main_queue_callback_4cf  30. corefoundation           0x02253af5 __cfrunlooprun  31. corefoundation           0x02252f44 cfrunlooprunspecific  32. corefoundation           0x02252e1b cfrunloopruninmode  33. foundation               0x013113ac -[nsrunloop(nsrunloop) runmode:beforedate:]  34. ???                      0x0000d981 [ibcocoatouchtool startservingreceivechannel:]  35. ???                      0x0000db1a [ibcocoatouchtool startservingwithsocket:]  36. ???                      0x0000ec89 [ibcocoatouchtool .cxx_destruct]  37. ???                      0x00002c15 ???  38. ???                      0x00000003 ??? exception info:{ }