Re: Question

[David Chisnall]

Hi Laurent,

This doesn't look like the code from trunk.  Are you using an old release?  As 
I said, I think this bug is fixed some months ago.

David

On 6 Mar 2013, at 01:12, Laurent Michel <address@hidden> wrote:

> David,
> 
> I recompiled and here is the trace:
> 
> Program received signal SIGSEGV, Segmentation fault.
> 0xb7a55695 in isEmptyProtocol (aProto=0xb7736f90) at protocol.c:62
> 62                    isEmpty &= (p2->properties->count == 0);
> (gdb) where
> #0  0xb7a55695 in isEmptyProtocol (aProto=0xb7736f90) at protocol.c:62
> #1  0xb7a5553e in unique_protocol (aProto=0xb7736f90) at protocol.c:118
> #2  0xb7a534eb in init_protocols (protocols=0xb7736fb0) at protocol.c:189
> #3  0xb7a534da in init_protocols (protocols=0xb773a0c0) at protocol.c:186
> #4  0xb7a5328a in objc_init_protocols (protocols=0xb773a0c0) at protocol.c:196
> #5  0xb7a48264 in load_category (cat=0xb773a2c0, class=0xb7a64340) at 
> category_loader.c:38
> #6  0xb7a47f02 in try_load_category (cat=0xb773a2c0) at category_loader.c:50
> #7  0xb7a47e6a in objc_try_load_category (cat=0xb773a2c0) at 
> category_loader.c:63
> #8  0xb7a5143f in __objc_exec_class (module=0xb773a398) at loader.c:89
> #9  0xb76c55a4 in .objc_load_function () from 
> /home/ldm/work/platform/Clo/queens2/../ORFoundation/libORFoundation.so
> #10 0xb7fece9b in ?? () from /lib/ld-linux.so.2
> #11 0xb7fecf84 in ?? () from /lib/ld-linux.so.2
> #12 0xb7fdf20f in ?? () from /lib/ld-linux.so.2
> 
> 
> So line 62. 
> 
> It won't show the variables though:
> 
> (gdb) p *p2
> $3 = {
>  isa = 0xb7a642f0, 
>  name = 0xb771df54 "ORExpr", 
>  protocol_list = 0xb7795a18, 
>  instance_methods = 0xb7795a20, 
>  class_methods = 0xb7795a20, 
>  optional_instance_methods = 0xb7795a20, 
>  optional_class_methods = 0xb7795a20, 
>  properties = 0x0, 
>  optional_properties = 0x0
> }
> (gdb) l
> 57            if (aProto->isa == ObjC2ProtocolClass)
> 58            {
> 59                    struct objc_protocol2 *p2 = (struct 
> objc_protocol2*)aProto;
> 60                    isEmpty &= (p2->optional_instance_methods->count == 0);
> 61                    isEmpty &= (p2->optional_class_methods->count == 0);
> 62                    isEmpty &= (p2->properties->count == 0);
> 63                    isEmpty &= (p2->optional_properties->count == 0);
> 64            }
> 65            return isEmpty;
> 66    }
> 
> So p2->properties is NULL and trying to access the count attribute crashes. 
> This is happening on a protocol
> of mine (ORExpr) which inherits from other protocols:
> 
> @protocol ORExpr <ORConstraint,NSObject,NSCoding>
> -(id<ORTracker>) tracker;
> -(ORInt) min;
> -(ORInt) max;
> -(BOOL) isConstant;
> -(BOOL) isVariable;
> 
> ....
> 
> @end
> 
> Any ideas?
> 
> 
> On Mar 5, 2013, at 7:20 AM, Laurent Michel <address@hidden> wrote:
> 
>> 
>> On Mar 5, 2013, at 4:10 AM, David Chisnall <address@hidden> wrote:
>> 
>>> Hi,
>>> 
>>> How old is your runtime?  Without debugging symbols, this looks like it 
>>> might be a bug that was fixed in May last year.  It would really help if 
>>> you could do a debug build of the runtime and let me know exactly what is 
>>> failing.  If you do ccmake . in your libobjc2 build directory, and change 
>>> the build type to Debug, you should get the symbols.
>> 
>> libobjc2 was 1.6.1
>> 
>> 
>> address@hidden:/usr/local/src/old$ sha1sum libobjc2-1.6.tar.gz 
>> 348ab64899b25ecb2bfdfd13ebeeab2d6a2c8988  libobjc2-1.6.tar.gz
>> 
>> 
>> total 9196
>> drwxr-xr-x 4 root root     4096 Mar  4 08:37 GNUstep
>> lrwxrwxrwx 1 root root       23 Mar  4 08:37 libgnustep-base.so -> 
>> libgnustep-base.so.1.24
>> lrwxrwxrwx 1 root root       25 Mar  4 08:37 libgnustep-base.so.1.24 -> 
>> libgnustep-base.so.1.24.3
>> -rwxr-xr-x 1 root root  9105637 Mar  4 08:36 libgnustep-base.so.1.24.3
>> -r--r--r-- 1 root root   136452 May 18  2012 libobjc.a
>> lrwxrwxrwx 1 root root       31 May 18  2012 libobjc.so -> 
>> /usr/local/lib/libobjc.so.4.6.0
>> lrwxrwxrwx 1 root root       31 May 18  2012 libobjc.so.4 -> 
>> /usr/local/lib/libobjc.so.4.6.0
>> lrwxrwxrwx 1 root root       31 May 18  2012 libobjc.so.4.6 -> 
>> /usr/local/lib/libobjc.so.4.6.0
>> -r--r--r-- 1 root root   140820 May 18  2012 libobjc.so.4.6.0
>> lrwxrwxrwx 1 root root       33 May 18  2012 libobjcxx.so -> 
>> /usr/local/lib/libobjcxx.so.4.6.0
>> lrwxrwxrwx 1 root root       33 May 18  2012 libobjcxx.so.4 -> 
>> /usr/local/lib/libobjcxx.so.4.6.0
>> lrwxrwxrwx 1 root root       33 May 18  2012 libobjcxx.so.4.6 -> 
>> /usr/local/lib/libobjcxx.so.4.6.0
>> -r--r--r-- 1 root root    13002 May 18  2012 libobjcxx.so.4.6.0
>> drwxrwsr-x 4 root staff    4096 Mar  3 13:33 python2.7
>> address@hidden:/usr/local/lib$ 
>> 
>> I was looking yesterday night for a more recent tar ball, but couldn't 
>> locate one. 
>> 
>> I'll recompile libobjc2 in debug and will update you. Thanks for the info 
>> David!
>> 
>> --
>> Laurent
>> 
>> 
>>> 
>>> David
>>> 
>>> On 5 Mar 2013, at 01:37, Laurent Michel <address@hidden> wrote:
>>> 
>>>> PS/ I decided to recompile GNUstep simply because I was experiencing a 
>>>> crash with my compiled binary during the 
>>>> library initializations of GNUstep/libobjc. Namely, here is the backtrace:
>>>> 
>>>> [Thread debugging using libthread_db enabled]
>>>> Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
>>>> [New Thread 0xb7021b40 (LWP 8378)]
>>>> 
>>>> Program received signal SIGSEGV, Segmentation fault.
>>>> 0xb7a58d50 in init_protocols () from /usr/local/lib/libobjc.so
>>>> (gdb) where
>>>> #0  0xb7a58d50 in init_protocols () from /usr/local/lib/libobjc.so
>>>> #1  0xb7a58c47 in init_protocols () from /usr/local/lib/libobjc.so
>>>> #2  0xb7a588c1 in objc_init_protocols () from /usr/local/lib/libobjc.so
>>>> #3  0xb7a517e3 in objc_try_load_category () from /usr/local/lib/libobjc.so
>>>> #4  0xb7a57251 in __objc_exec_class () from /usr/local/lib/libobjc.so
>>>> #5  0xb76d15d4 in .objc_load_function () from 
>>>> /home/ldm/work/platform/Clo/queens2/../ORFoundation/libORFoundation.so
>>>> #6  0xb7fece9b in ?? () from /lib/ld-linux.so.2
>>>> #7  0xb7fecf84 in ?? () from /lib/ld-linux.so.2
>>>> #8  0xb7fdf20f in ?? () from /lib/ld-linux.so.2
>>>> (gdb) quit
>>>> A debugging session is active.
>>> 
>>> --
>>> This email complies with ISO 3103
>>> 
>>> 
>>> _______________________________________________
>>> Gnustep-dev mailing list
>>> address@hidden
>>> https://lists.gnu.org/mailman/listinfo/gnustep-dev
>> 
> 
> 
> _______________________________________________
> Gnustep-dev mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/gnustep-dev




-- Sent from my Difference Engine