[PATCH next 4/7] minmax.h: Use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()

David Laight posted 7 patches 3 days, 1 hour ago
[PATCH next 4/7] minmax.h: Use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
Posted by David Laight 3 days, 1 hour ago
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.

Signed-off-by: David Laight <david.laight@aculab.com>
---
 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");		\
-- 
2.17.1

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