Subject: [PATCH v2 24/27 5.10.y] minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()

From: Eliav Farber <[email-masked]>
Date: Fri, 17 Oct 2025 09:05:16 +0000

From: David Laight <[email-masked]>

[ 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/[email-masked]
Signed-off-by: David Laight <[email-masked]>
Cc: Andy Shevchenko <[email-masked]>
Cc: Arnd Bergmann <[email-masked]>
Cc: Christoph Hellwig <[email-masked]>
Cc: Dan Carpenter <[email-masked]>
Cc: Jason A. Donenfeld <[email-masked]>
Cc: Jens Axboe <[email-masked]>
Cc: Lorenzo Stoakes <[email-masked]>
Cc: Mateusz Guzik <[email-masked]>
Cc: Matthew Wilcox <[email-masked]>
Cc: Pedro Falcato <[email-masked]>
Signed-off-by: Andrew Morton <[email-masked]>
Signed-off-by: Eliav Farber <[email-masked]>
---
 include/linux/minmax.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

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");		\
-- 
2.47.3