[waffle] [PATCH 4/4] wgl: attempt to fix the final test

[Emil Velikov]

On 19/08/14 14:34, Emil Velikov wrote:
> On 19/08/14 13:42, Jose Fonseca wrote:
>> On 12/08/14 16:37, Emil Velikov wrote:
>>> MSVC helps us out with the final test by undicating that we're
>>> corrupting the stack, which begs the question - at which point are we
>>> messing up with the calling conventions. This patch attempts to resolve
>>> that yet the bug still persists :'(
>>>
>>> Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
>>> ---
>>>   src/waffle/core/wcore_error_unittest.c | 4 ++++
>>>   third_party/threads/threads.h          | 2 +-
>>>   2 files changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/src/waffle/core/wcore_error_unittest.c
>>> b/src/waffle/core/wcore_error_unittest.c
>>> index 5176031..8b9b334 100644
>>> --- a/src/waffle/core/wcore_error_unittest.c
>>> +++ b/src/waffle/core/wcore_error_unittest.c
>>> @@ -148,7 +148,11 @@ struct thread_arg {
>>>   };
>>>
>>>   /// The start routine given to threads in test wcore_error.thread_local.
>>> +#if !defined(_WIN32)
>>>   static bool
>>> +#else
>>> +static bool __stdcall
>>> +#endif
>>>   thread_start(struct thread_arg *a)
>>>   {
>>>       static const enum waffle_error error_codes[NUM_THREADS] = {
>>> diff --git a/third_party/threads/threads.h b/third_party/threads/threads.h
>>> index 4e7dba2..eb024dd 100644
>>> --- a/third_party/threads/threads.h
>>> +++ b/third_party/threads/threads.h
>>> @@ -117,7 +117,7 @@ typedef pthread_once_t  once_flag;
>>>
>>>   /*---------------------------- types ----------------------------*/
>>>   typedef void (*tss_dtor_t)(void*);
>>> -typedef int (*thrd_start_t)(void*);
>>> +typedef int (__stdcall *thrd_start_t)(void*);
>>>
>>>   struct xtime {
>>>       time_t sec;
>>>
>>
>>
>> Sorry, I've been on PTO and I haven't caught up with email.
>>
>> What is the problem here again?
>>
> We end up with stack corruption in test_wcore_error_thread_local().
> 
> The documentation indicates [1] that the function pointer passed to
> _beginthreadex (in our third_party/threads code) should use __stdcall calling
> convention. I'm not entirely sure which/how many pieces we need to annotate
> due to the amount of function pointers passed around :'(
> 
Actually _beginthreadex() is correctly setup, yet pack.func(pack.arg) (from
impl_thrd_routine) may not be. So many functions passing around func pointers
is making my head spin.

You should be able to reproduce by building waffle and giving 'make check'* a try.

-Emil

* 'cmake --build %BUILDDIR --target check-func'


> third_party/threads:   _beginthreadex
> third_party/threads:   thrd_create
> src/waffle/wcore:      test_wcore_error_thread_local//thread_start
> third_party/src/cmoka: run_tests
> 
> Any suggestions/ideas would be appreciated
> -Emil
> 
> [1] http://msdn.microsoft.com/en-us/library/kdzttdcb.aspx
> 
>> Jose
>