[Intel-gfx] [PATCH i-g-t 1/3] lib/core: Avoid unused result in backtrace printing

[Tvrtko Ursulin]

On 03/11/2017 12:10, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2017-11-03 12:04:15)
>>
>> On 03/11/2017 11:52, Chris Wilson wrote:
>>> Quoting Tvrtko Ursulin (2017-11-03 11:47:54)
>>>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>>>
>>>> Add helpers for direct write to stderr to consolidate the code
>>>> and avoid the unused result warning in build.
>>>>
>>>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>>> ---
>>>>    lib/igt_core.c | 23 ++++++++++++++++-------
>>>>    1 file changed, 16 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/lib/igt_core.c b/lib/igt_core.c
>>>> index 538a4472e209..351859eaa04c 100644
>>>> --- a/lib/igt_core.c
>>>> +++ b/lib/igt_core.c
>>>> @@ -1239,7 +1239,7 @@ static const char hex[] = "0123456789abcdef";
>>>>    static void
>>>>    xputch(int c)
>>>>    {
>>>> -       write(STDERR_FILENO, (const void *) &c, 1);
>>>> +       igt_assert_eq(write(STDERR_FILENO, (const void *) &c, 1), 1);
>>>
>>> Infinite recursion, you can't use an assert from inside the assert
>>> handler.
>>
>> I thought it is the signal handler. Tested sending some signals and it
>> survived. If there is a flaw there could instead nerf them with void
>> cast, don't know.
> 
> I do recall these are meant to be fail safe, so using something like
> assert which may end up here again is no-no. igt_ignore_warn()?

But then on the other hand igt_fail seems to have handling for exit 
handlers using igt_asserts. Which suggests what I've done might be fine 
after all.

Regards,

Tvrtko