[Intel-gfx] [PATCH i-g-t] libs/igt_core.c: Fix compile warnings in igt_core.c

[Damien Lespiau]

On Wed, May 20, 2015 at 08:37:56AM +0000, Morton, Derek J wrote:
>  
> >> > -----Original Message-----
> >> > From: Morton, Derek J
> >> > Sent: Tuesday, May 19, 2015 12:21 PM
> >> > To: intel-gfx at lists.freedesktop.org
> >> > Cc: Wood, Thomas; Gore, Tim; Morton, Derek J
> >> > Subject: [PATCH i-g-t] libs/igt_core.c: Fix compile warnings in 
> >> > igt_core.c
> >> > 
> >> > Fixed variables incorrectly declared as signed instead of unsigned.
> >
> >Which kind of compiler warning is this? Imo
> >
> >	for (unsigned int i = 0; i < something; i++)
> >
> >is just not C style, the int there is perfectly fine. We've had this
> >problem before with Android going ridiculously overboard with
> >>compiler warnings, and the solution back then was to remove all the
> >>silly ones for igt. It smells like the same is appropriate for this
> >>>one here too.
> >
> 
> The warning occurs because 'something' is of an unsigned type. In this
> case the macro ARRAY_SIZE uses sizeof() which returns an unsigned
> type. Implicit conversion between signed and unsigned types has always
> resulted in compiler warnings in my experience. It is not something
> android specific.

unsigned int like that is C99 and the sizeof operator is a size_t, so
maybe use that instead of unsigned int?

> 
> >> > Fixed 'unused parameter' warning from signal handlers that were
> >> > not using the signal parameter.
> >
> >Yeah unused variable because you compile out assert isn't good, it
> >will at least break a bunch of library unit tests (the ones in
> >>lib/tests). I guess you don't run them in your Android builds?
> >>-Daniel
> 
> I have no idea why the asserts are compiled out for android. Tim had
> some suggestions which need investigating. A subject for another patch
> I guess.  We do not run the unit tests on android because it has not
> been possible to run them since they were moved to libs/test. The
> android make file was never updated when they were moved.  I need to
> look at look at writing a new unit test for the fatal_signal_handler
> so will look at getting them to build for android at the same time.
> 
> As the unused parameter changes are more controversial I will remove
> them for now and update the patch to just fix the signed / unsigned
> warnings.

FWIW, I'd used the gcc unused attribute for things like that instead of
those void expressions.

#define __unused __attribute__((unused))

void foo(int bar __unused)
{
  ...
}

-- 
Damien