Bug 84750 – AccessibilityUIElement needs to stop throwing Obj-C exceptions

• Status: NEW
• Component: Accessibility

[Simon Fraser (smfr)]

Some bots show this crash:

http://build.webkit.org/results/Lion%20Release%20(WebKit2%20Tests)/r115078%20(6779)/platform/mac/accessibility/misspelled-attributed-string-stderr.txt

We need to catch these exceptions.

2012-04-24 11:55:38.076 WebProcess[6148:403] An uncaught exception was raised
2012-04-24 11:55:38.077 WebProcess[6148:403] NSMutableRLEArray objectAtIndex:effectiveRange:: Out of bounds
2012-04-24 11:55:38.099 WebProcess[6148:403] (
	0   CoreFoundation                      0x00007fff9a5e4fc6 __exceptionPreprocess + 198
	1   libobjc.A.dylib                     0x00007fff8e343d5e objc_exception_throw + 43
	2   CoreFoundation                      0x00007fff9a5e4dfa +[NSException raise:format:arguments:] + 106
	3   CoreFoundation                      0x00007fff9a5e4d84 +[NSException raise:format:] + 116
	4   Foundation                          0x00007fff951a228d -[NSRLEArray objectAtIndex:effectiveRange:] + 117
	5   Foundation                          0x00007fff951a49b1 -[NSConcreteMutableAttributedString addAttribute:value:range:] + 166
	6   WebCore                             0x000000010ffe1239 _ZL28AXAttributedStringAppendTextP25NSMutableAttributedStringPN7WebCore4NodeEPKti + 2361
	7   WebCore                             0x000000010ffe03bb -[WebAccessibilityObjectWrapper doAXAttributedStringForTextMarkerRange:] + 1387
	8   WebCore                             0x000000010ffeb62d -[WebAccessibilityObjectWrapper doAXAttributedStringForRange:] + 205
	9   WebCore                             0x000000010fff0957 -[WebAccessibilityObjectWrapper accessibilityAttributeValue:forParameter:] + 19975
	10  WebKitTestRunnerInjectedBundle      0x0000000112ad2c92 _ZN3WTR22AccessibilityUIElement33attributedStringRangeIsMisspelledEjj + 68
	11  WebKitTestRunnerInjectedBundle      0x0000000112ad6edb _ZN3WTR24JSAccessibilityUIElement33attributedStringRangeIsMisspelledEPK15OpaqueJSContextP13OpaqueJSValueS5_mPKPKS4_PS7_ + 109
	12  JavaScriptCore                      0x000000010f1b5649 _ZN3JSC18JSCallbackFunction4callEPNS_9ExecStateE + 361
	13  JavaScriptCore                      0x000000010f2b112e _ZN3JSC5LLInt9setUpCallEPNS_9ExecStateEPNS_11InstructionENS_22CodeSpecializationKindENS_7JSValueEPNS_17LLIntCallLinkInfoE + 142
	14  JavaScriptCore                      0x000000010f2afb60 llint_slow_path_call + 96
	15  JavaScriptCore                      0x000000010f2b46bc llint_op_call + 142
	16  JavaScriptCore                      0x000000010f16afcc _ZN3JSC11Interpreter7executeEPNS_14EvalExecutableEPNS_9ExecStateENS_7JSValueEPNS_14ScopeChainNodeEi + 1244
	17  JavaScriptCore                      0x000000010f16aa88 _ZN3JSC4evalEPNS_9ExecStateE + 1304
	18  JavaScriptCore                      0x000000010f2afdc8 llint_slow_path_call_eval + 200
	19  JavaScriptCore                      0x000000010f2b47b7 llint_op_call_eval + 23
	20  JavaScriptCore                      0x000000010f16daab _ZN3JSC11Interpreter7executeEPNS_17ProgramExecutableEPNS_9ExecStateEPNS_14ScopeChainNodeEPNS_8JSObjectE + 3083
	21  JavaScriptCore                      0x000000010f0f2d28 _ZN3JSC8evaluateEPNS_9ExecStateEPNS_14ScopeChainNodeERKNS_10SourceCodeENS_7JSValueEPS7_ + 344
	22  WebCore                             0x000000010fe64e69 _ZN7WebCore16ScriptController15evaluateInWorldERKNS_16ScriptSourceCodeEPNS_15DOMWrapperWorldE + 425
	23  WebCore                             0x000000010fe64fa9 _ZN7WebCore16ScriptController8evaluateERKNS_16ScriptSourceCodeE + 41
	24  WebCore                             0x000000010fe6cebb _ZN7WebCore13ScriptElement13executeScriptERKNS_16ScriptSourceCodeE + 155
	25  WebCore                             0x000000010fe6bef6 _ZN7WebCore13ScriptElement13prepareScriptERKN3WTF12TextPositionENS0_17LegacyTypeSupportE + 1078
	26  WebCore                             0x000000010f8a27cf _ZN7WebCore16HTMLScriptRunner9runScriptEPNS_7ElementERKN3WTF12TextPositionE + 303
	27  WebCore                             0x000000010f8a2650 _ZN7WebCore16HTMLScriptRunner7executeEN3WTF10PassRefPtrINS_7ElementEEERKNS1_12TextPositionE + 48
	28  WebCore                             0x000000010f8549e4 _ZN7WebCore18HTMLDocumentParser30runScriptsForPausedTreeBuilderEv + 84
	29  WebCore                             0x000000010f854aa8 _ZN7WebCore18HTMLDocumentParser16canTakeNextTokenENS0_15SynchronousModeERNS_11PumpSessionE + 88
	30  WebCore                             0x000000010f85477c _ZN7WebCore18HTMLDocumentParser13pumpTokenizerENS0_15SynchronousModeE + 268
	31  WebCore                             0x000000010f854e17 _ZN7WebCore18HTMLDocumentParser6appendERKNS_15SegmentedStringE + 231
	32  WebCore                             0x000000010f639259 _ZN7WebCore25DecodedDataDocumentParser11appendBytesEPNS_14DocumentWriterEPKcm + 313
	33  WebCore                             0x000000010f6644ed _ZN7WebCore14DocumentLoader10commitDataEPKcm + 157
	34  WebKit2                             0x000000010ec86fbe _ZN6WebKit20WebFrameLoaderClient13committedLoadEPN7WebCore14DocumentLoaderEPKci + 60
	35  WebCore                             0x000000010f6643e9 _ZN7WebCore14DocumentLoader10commitLoadEPKci + 153
	36  WebCore                             0x000000010fe4b2d5 _ZN7WebCore14ResourceLoader14didReceiveDataEPKcixb + 53
	37  WebCore                             0x000000010fc916db _ZN7WebCore18MainResourceLoader14didReceiveDataEPKcixb + 651
	38  WebCore                             0x000000010fe4b902 _ZN7WebCore14ResourceLoader14didReceiveDataEPNS_14ResourceHandleEPKcii + 130
	39  Foundation                          0x00007fff951993a9 ___NSURLConnectionDidReceiveData_block_invoke_1 + 144
	40  Foundation                          0x00007fff95199313 _NSURLConnectionDidReceiveData + 86
	41  CFNetwork                           0x00007fff99af9c08 _ZN19URLConnectionClient21_clientDidReceiveDataEPK9__CFArrayPNS_26ClientConnectionEventQueueE + 348
	42  CFNetwork                           0x00007fff99bab8fb _ZN19URLConnectionClient26ClientConnectionEventQueue33processAllEventsAndConsumePayloadEP20XConnectionEventInfoI12XClientEvent18XClientEventParamsEl + 827
	43  CFNetwork                           0x00007fff99ad6389 _ZN19URLConnectionClient13processEventsEv + 185
	44  CFNetwork                           0x00007fff99ad622e _ZN17MultiplexerSource7performEv + 212
	45  CoreFoundation                      0x00007fff9a5536e1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
	46  CoreFoundation                      0x00007fff9a552f4d __CFRunLoopDoSources0 + 253
	47  CoreFoundation                      0x00007fff9a579d39 __CFRunLoopRun + 905
	48  CoreFoundation                      0x00007fff9a579676 CFRunLoopRunSpecific + 230
	49  HIToolbox                           0x00007fff9a21831f RunCurrentEventLoopInMode + 277
	50  HIToolbox                           0x00007fff9a21f5c9 ReceiveNextEventCommon + 355
	51  HIToolbox                           0x00007fff9a21f456 BlockUntilNextEventMatchingListInMode + 62
	52  AppKit                              0x00007fff93fcaf5d _DPSNextEvent + 659
	53  AppKit                              0x00007fff93fca861 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 135
	54  AppKit                              0x00007fff93fc719d -[NSApplication run] + 470
	55  WebCore                             0x000000010fe5c16f _ZN7WebCore7RunLoop3runEv + 63
	56  WebKit2                             0x000000010ece1c1a _ZN6WebKit14WebProcessMainERKNS_11CommandLineE + 2490
	57  WebKit2                             0x000000010ec95f67 WebKitMain + 285
	58  WebProcess                          0x000000010e9d9e5f main + 219
	59  WebProcess                          0x000000010e9d9d7c start + 52

[chris fleizach]

yep it should be doing this

[chris fleizach]

actually, AccessibilityUIElement is set up to catch NSAccessibilityException. 

I don't feel like this should be fixed because it will mask problems like these, which are real

[Alexey Proskuryakov]

See also: bug 39885.

[Simon Fraser (smfr)]

I think it should be fixed. We never want Obj-C exceptions to propagate. However, we can log when we catch them.

[Simon Fraser (smfr)]

Oh, I see AccessibilityUIElement is DRT-only. In that case I don't much care, but we need to stop it throwing.

[chris fleizach]

(In reply to comment #5)
> Oh, I see AccessibilityUIElement is DRT-only. In that case I don't much care, but we need to stop it throwing.

Agreed. I am working on the actual exception error. hopefully will have a fix tonite

[James Craig]

BRB: Is this still a valid issue? Sam thinks it may be fixed.

[Radar WebKit Bug Importer]

<rdar://problem/15710292>