Segfault

[Jef Driesen]

On 12-02-13 20:05, Dirk Hohndel wrote:
> Jef Driesen <jefdriesen at telenet.be> writes:
>>>>
>>>> In the first case (bt1.log), I created a new file, and downloaded data
>>>> from a dive computer. Right after the download finishes, I hit the
>>>> segfault. For the second case (bt2.log), I started subsurface with the
>>>> command "./subsurface dives/*.xml". When selecting some dives in the
>>>> treeview, a segfault again.
>>>>
>>>> I can reproduce these segfaults every time.
>>>>
>>>> Jef#0  __strlen_sse2_pminub () at ../sysdeps/x86_64/multiarch/strlen-sse2-pminub.S:39
>>>> #1  0x00007ffff61422d2 in g_strdup () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
>>>
>>> Since the code in set_one_cylinder explicitly tests that we don't pass
>>> in a NULL for description and that's the only string involved here, my
>>> only guess would be that you are passing in a completely bogus but
>>> non-NULL pointer.
>>>
>>> I just don't see how that could happen...
>>>
>>> Can you set a breakpoint in set_one_cylinder and take a look at what's
>>> in cyl ?
>>
>> The description field contains a bogus pointer (0x2300000006e). Smells like
>> memory corruption. I have the impression the dive pointer might have been freed
>> already, because also other pointers are out of bounds:
>>
>> (gdb) p dive->suit
>> $8 = 0xbb00000000 <Address 0xbb00000000 out of bounds>
>> (gdb) p dive->dc.model
>> $9 = 0x54ed0001013a <Address 0x54ed0001013a out of bounds>
>
> Beautiful. Do you have Valgrind installed? That's usually the best to
> catch issues like this.
>
> Or do you have a way to reproduce this that does NOT require a
> divecomputer download? Then I can look into this here. I tried what you
> described in the text above for the second case and wasn't able to get
> it to SIGSEGV...

Mystery solved. For some unknown reason, some of the object files were 
out-of-date and didn't get rebuild properly with just "make". After a full 
rebuild (eg after "make clean" first) everything is working fine now. Sorry for 
the trouble.

Jef