On Mon, Apr 18, 2016 at 03:40:11PM +0100, Emil Velikov wrote: > On 18 April 2016 at 13:36, Daniel Vetter <daniel at ffwll.ch> wrote: > > On Mon, Apr 18, 2016 at 12:09:51PM +0100, Lionel Landwerlin wrote: > >> Ping? > >> > >> On 22/03/16 14:10, Lionel Landwerlin wrote: > >> >When extracting the value at full precision (16 bits), no need to > >> >round the value. > >> > > >> >This was spotted by Jani when running sparse. Unfortunately this fix > >> >doesn't get rid of the warning. > > > > It sounded like no bug, and the patch itself fails to appease sparse. And > > I didn't check what's upsetting sparse itself, so figured "nothing to do > > here until a real fix shows up". > > > According to the C99 standard a left shift with negative value is > undefined. And we're hitting this case at full precision ;-)
Well commit message says sparse is still unhappy. So I'm not sure whether the fix is good enough? And the issue with compiler/static checker noise is that we really should aim to shut them up completely, because broken windows and all that (even if it's sometimes a fallacy, I think it applies here). -Daniel > > > Should I do something here? > Having the above information in, optionally with the warning message > in place of the current commit message would be recommended imho. > > After all the patch is a definite fix, even if I personally I'd write > the inline helper via a switch (makes things dead obvious). > > Regardless, > Reviewed-by: Emil Velikov <emil.velikov at collabora.com> > > -Emil -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch