[webkit-dev] WebKit on OpenBSD

[Maciej Stachowiak]

On May 30, 2008, at 1:51 PM, James Turner wrote:

> On Fri, May 30, 2008 at 12:22:54PM -0700, Maciej Stachowiak wrote:
>>
>> On May 30, 2008, at 12:15 PM, James Turner wrote:
>>
>>> On Fri, May 30, 2008 at 12:13:43PM -0700, Maciej Stachowiak wrote:
>>>>
>>>> On May 30, 2008, at 10:37 AM, James Turner wrote:
>>>>
>>>>> I've spent the last couple days trying to compile WebKit on  
>>>>> OpenBSD
>>>>> -current.  After adding the signbit function, changing isfinite to
>>>>> finite and adding the missing pthread_attr_get_np function, I was
>>>>> finally able to get it to compile.
>>>>>
>>>>> However, when I try to run the Gtk test browser or midori  
>>>>> (another gtk
>>>>> browser based on webkit), I receive or core dump whenever I  
>>>>> click on any
>>>>> part of a webpage or try to navigate to another.  After  
>>>>> inspecting the
>>>>> core dump with gdb I'm left with this:
>>>>>
>>>>> #0  0x0d501dc8 in KJS::Collector::markStackObjectsConservatively  
>>>>> () from
>>>>> /usr/local/lib/libwebkit-1.0.so.1.0
>>>>
>>>> Sounds like pthread_attr_get_np is not working as expected. It is  
>>>> used to
>>>> get the stack base, for purposes of the conservative garbage  
>>>> collector.
>>>>
>>>> - Maciej
>>>
>>> Thanks, I'll look into my implementation and check it with people  
>>> who
>>> actually know what they're doing!
>>
>> pthread_attr_get_np is not really all that important, just any way  
>> to get
>> the stack base. If OpenBSD has any function at all that works for  
>> that
>> purpose you could just add another branch to the ifdef. Regrettably  
>> there
>> is no portable way to do it.
>>
>> - Maciej
>
> So, I looked through OpenBSD's diff stack function and tried using
> pthread_stackseg_np like:
>
> stack_t stack;
> pthread_stackseg_np(thread, &stack);
>
> But I'm still getting a segfault at the same location.  This again  
> could
> be the wrong function to use, but it's the only thing I can find that
> looks remotely like it would work :/

It sounds like it should work (looks analogous to the Solaris  
thr_stksegment). Can you try in the debugger? You should be able to  
see if it is trying to access an address outside the stack range, or  
doing an unaligned access, or something.

Regards,
Maciej