Re: crash in NSPathUtilies / UserDefaults (from PikoPixel)

[Riccardo Mottola]

Hallo,

Fred Kiefer wrote:
> Hi Riccardo,
>
> if you look at the line NSProcessInfo.m:1015 you will find:
>
>    _NSLog_printf_handler(_GNU_MISSING_MAIN_FUNCTION_CALL);
>
> Now it is definitely a problem that this line leads to a recursion and
> somebody with more base knowledge should look into that. Most liekly the

Interesting is that there is a comment that NSAssert that can't be used 
to avoid recursion.

I put a breakpoint exactly there (NSProcessInfo.m:1015), the stack is 
not yet corrupted. I copy it below.

As one can think,
(gdb) p _gnu_processName
$1 = (struct NSString *) 0x0
(gdb) p _gnu_arguments
$2 = (struct NSArray *) 0x0
(gdb) p _gnu_environment
$3 = (struct NSDictionary *) 0x0

they are all NULL, probably they shouldn't, since that is the assert, 
however again, we shouldn't get a crash in the print statement: two bugs 
in one. I think this is stuff in base.

Thanks to this we know that the PP trace is:
PPAppBootUtilities.m:42
PPGNUstepGlue_TitleablePopUpButton.m:70

It looks as there is an invalid selector and this causes a crash.

I commented out + (void) load of PPGNUstepGlue_TitleablePopUpButton.m

But again I get a stimilar recursive stacktrace where the UserName is 
invalid.

All other application seem to run quite fine, I did run base tests and 
it doesn't look so bad:
7992 Passed tests
  38 Dashed hopes
   6 Failed tests
   5 Skipped sets

Only 6 failures:
Failed test:     RecursiveLock.m:36 ... NSRecursiveLock 
isLockedByCurrentThread returns NO when not locked
Failed test:     RecursiveLock.m:39 ... NSRecursiveLock 
isLockedByCurrentThread returns YES when not locked
Failed test:     RecursiveLock.m:42 ... NSRecursiveLock 
isLockedByCurrentThread returns NO when unlocked
Failed test:         basic10_4.m:111 ... format width set correctly
Failed test:         basic10_4.m:115 ... positive prefix set correctly
Failed test:         basic10_4.m:145 ... negativeFormat used for -ve number

and none seems to be related, although... well there should be none.

> function GSPrivateDefaultsFlag() needs another safety hatch. But the
> problem seems not to be related to PikoPixel directly. The only possible
> connection that I see is that there user defaults get set from a +load
> method (PPGNUstepGlue_ModifierKeys.m). You could comment out the code in
> that +load method and see if this changes the behaviour for you.

Unfortunately, it doesn't help.

Riccardo


trace:
#0  +[NSProcessInfo processInfo] (self=0xbb70f080 <_OBJC_Class_NSProcessInfo>,
    _cmd=0xbb706b70 <_OBJC_SELECTOR_TABLE+400>) at NSProcessInfo.m:1015
#1  0xbb45f49d in InitialisePathUtilities () at NSPathUtilities.m:1154
#2  0xbb466d5b in GSDefaultsRootForUser (address@hidden)
    at NSPathUtilities.m:1883
#3  0xbb4efe3f in -[NSUserDefaults initWithUser:] (address@hidden,
    address@hidden <_OBJC_SELECTOR_TABLE+624>, userName=0xb8cf1830)
    at NSUserDefaults.m:1180
#4  0xbb4ef964 in -[NSUserDefaults init] (self=0xb8c61cd0,
    _cmd=0xbb731778 <_OBJC_SELECTOR_TABLE+408>) at NSUserDefaults.m:1094
#5  0xbb4f0369 in +[NSUserDefaults standardUserDefaults] (
    self=0xbb731a60 <_OBJC_Class_NSUserDefaults>,
    _cmd=0xbb731758 <_OBJC_SELECTOR_TABLE+376>) at NSUserDefaults.m:779
#6  0xbb4f2467 in GSPrivateDefaultsFlag (address@hidden)
    at NSUserDefaults.m:2116
#7  0xbb441447 in NSLogv (address@hidden <_OBJC_INSTANCE_2>,
    address@hidden "\260f\302\270\220\034\306\270\220\300\313\270$") at 
NSLog.m:354
#8  0xbb441957 in NSLog (address@hidden <_OBJC_INSTANCE_2>)
    at NSLog.m:297
#9  0xbb392004 in +[NSAutoreleasePool addObject:] (
    self=0xbb6cecc0 <_OBJC_Class_NSAutoreleasePool>,
    _cmd=0xbb703eb8 <_OBJC_SELECTOR_TABLE+120>, anObj=0xb8c266b0)
    at NSAutoreleasePool.m:538
#10 0xbb456e93 in -[NSObject autorelease] (self=0xb8c266b0,
    _cmd=0xbb6fcda0 <_OBJC_SELECTOR_TABLE+32>) at NSObject.m:1874
#11 0xbb44321f in +[NSMethodSignature signatureWithObjCTypes:] (
    self=0xbb6fce20 <_OBJC_Class_NSMethodSignature>,
    _cmd=0xbb743b40 <_OBJC_SELECTOR_TABLE>,
    t=0x818f799 <_OBJC_METH_VAR_TYPE_0> "address@hidden:4:8") at 
NSMethodSignature.m:559
#12 0xbb5240fd in gs_objc_msg_forward2 (
    receiver=0xbb704060 <_OBJC_Class_NSObject>,
    sel=0x81901b8 <_OBJC_SELECTOR_TABLE+824>) at GSFFIInvocation.m:163
#13 0xbb2958d1 in __objc_get_forward_imp () from /usr/lib/libobjc.so.4
#14 0xbb2970d2 in objc_msg_lookup () from /usr/lib/libobjc.so.4
#15 0x080bdcfc in PPAppBootUtils_PerformNSObjectSelectorAfterAppLoads (
    address@hidden <_OBJC_SELECTOR_TABLE+936>)
    at PPAppBootUtilities.m:42
#16 0x080cc87f in +[NSObject(PPGNUstepGlue) TitleablePopUpButton_load] (
    self=0xbb704060 <_OBJC_Class_NSObject>, _cmd=0xb8c156d0)
    at PPGNUstepGlue_TitleablePopUpButton.m:70
#17 0xbb29a279 in ?? () from /usr/lib/libobjc.so.4
#18 0xbb29a622 in ?? () from /usr/lib/libobjc.so.4
#19 0xbb29b073 in __objc_exec_class () from /usr/lib/libobjc.so.4
#20 0x080ce3db in __objc_gnu_init ()
#21 0x080518d5 in ?? ()