On Tue, Mar 21, 2017 at 09:56:52AM +0000, Chris Wilson wrote:
On Mon, Mar 20, 2017 at 10:40:28AM +0100, Arnd Bergmann wrote:
We get a warning with gcc-7 about a pointless comparison when using a linear memmap:
drivers/gpu/drm/i915/selftests/scatterlist.c: In function 'alloc_table': drivers/gpu/drm/i915/selftests/scatterlist.c:219:66: error: self-comparison always evaluates to false [-Werror=tautological-compare]
Splitting out the comparison into a separate function avoids the warning and makes it slightly more obvious what happens.
I worried whether gcc will simply get smarter and apply its warning more consistently, but I agree the helper is good documentation.
Fixes: 935a2f776aa5 ("drm/i915: Add some selftests for sg_table manipulation") Signed-off-by: Arnd Bergmann arnd@arndb.de
Reviewed-by: Chris Wilson chris@chris-wilson.co.uk
And applied. -Chris