diff mbox series

[v2,16/19,5.15.y] minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()

Message ID 20251003130006.41681-17-farbere@amazon.com (mailing list archive)
State New
Headers
Series Backport minmax.h updates from v6.17-rc7 |

Commit Message

Eliav Farber Oct. 3, 2025, 1 p.m. UTC 
From: David Laight <David.Laight@ACULAB.COM>

[ Upstream commit a5743f32baec4728711bbc01d6ac2b33d4c67040 ]

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: David 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eliav Farber <farbere@amazon.com>
---
 include/linux/minmax.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 6f7ea669d305..91aa1b90c1bb 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -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");		\