linux/kernel.h: Fix warning seen with W=1 due to change in DIV_ROUND_CLOSEST
After commit b6d86d3d (Fix DIV_ROUND_CLOSEST to support negative dividends), the following warning is seen if the kernel is compiled with W=1 (-Wextra): warning: comparison of unsigned expression >= 0 is always true The warning is due to the test '((typeof(x))-1) >= 0', which is used to detect if the variable type is unsigned. Research on the web suggests that the warning disappears if '>' instead of '>=' is used for the comparison. Tests after changing the macro along that line show that the warning is gone, and that the result is still correct: i=-4: DIV_ROUND_CLOSEST(i, 2)=-2 i=-3: DIV_ROUND_CLOSEST(i, 2)=-2 i=-2: DIV_ROUND_CLOSEST(i, 2)=-1 i=-1: DIV_ROUND_CLOSEST(i, 2)=-1 i=0: DIV_ROUND_CLOSEST(i, 2)=0 i=1: DIV_ROUND_CLOSEST(i, 2)=1 i=2: DIV_ROUND_CLOSEST(i, 2)=1 i=3: DIV_ROUND_CLOSEST(i, 2)=2 i=4: DIV_ROUND_CLOSEST(i, 2)=2 Code size is the same as before. Signed-off-by:Guenter Roeck <linux@roeck-us.net> Tested-by:
Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by:
Jean Delvare <khali@linux-fr.org>
parent
521cf648
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