From f3fb126fdc9e148da38a6e25d7fc609774a99fc3 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 6 Nov 2025 16:20:51 +0100 Subject: [PATCH] math.h: amend abs() kernel-doc and add a note about signed type limits - amend the kernel-doc so the description is decoupled from the parameter descriptions. - add a note to explain behaviour for the signed types when supplied value is the minimum (e.g., INT_MIN for int type). Link: https://lkml.kernel.org/r/20251106152051.2361551-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Cc: Jonathan Cameron Signed-off-by: Andrew Morton --- include/linux/math.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/include/linux/math.h b/include/linux/math.h index 0198c92cbe3ef..6dc1d1d32fbc8 100644 --- a/include/linux/math.h +++ b/include/linux/math.h @@ -148,11 +148,16 @@ __STRUCT_FRACT(u32) /** * abs - return absolute value of an argument - * @x: the value. If it is unsigned type, it is converted to signed type first. - * char is treated as if it was signed (regardless of whether it really is) - * but the macro's return type is preserved as char. + * @x: the value. * - * Return: an absolute value of x. + * If it is unsigned type, @x is converted to signed type first. + * char is treated as if it was signed (regardless of whether it really is) + * but the macro's return type is preserved as char. + * + * NOTE, for signed type if @x is the minimum, the returned result is undefined + * as there is not enough bits to represent it as a positive number. + * + * Return: an absolute value of @x. */ #define abs(x) __abs_choose_expr(x, long long, \ __abs_choose_expr(x, long, \ -- 2.47.3