Commit a5743f32 authored by David Laight's avatar David Laight Committed by Andrew Morton
Browse files

minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp() 

Use BUILD_BUG_ON_MSG(statically_true(ulo > uhi), ...) for the sanity check
of the bounds in clamp().  Gives better error coverage and one less
expansion of the arguments.

Link: https://lkml.kernel.org/r/34d53778977747f19cce2abb287bb3e6@AcuMS.aculab.com


Signed-off-by: default avatarDavid Laight <david.laight@aculab.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent b280bb27

include/linux/minmax.h

+1 −2
Original line number Diff line number Diff line
@@ -106,8 +106,7 @@ 
	__auto_type uval = (val);						\

	__auto_type ulo = (lo);							\

	__auto_type uhi = (hi);							\

	static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)), 	\

			(lo) <= (hi), true),					\

	BUILD_BUG_ON_MSG(statically_true(ulo > uhi),				\

		"clamp() low limit " #lo " greater than high limit " #hi);	\

	BUILD_BUG_ON_MSG(!__types_ok3(uval, ulo, uhi),				\

		"clamp("#val", "#lo", "#hi") signedness error");		\