[PATCH 12/15 6.6.y] minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
From: Eliav Farber <hidden>
Date: 2025-09-22 10:39:43
Also in:
amd-gfx, bpf, dm-devel, dri-devel, linux-btrfs, linux-can, linux-edac, linux-hwmon, linux-input, linux-kselftest, linux-media, linux-mm, linux-scsi, linux-staging, linux-sunxi, linux-um, lkml, netdev, platform-driver-x86, stable
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: David Laight <redacted>
[ 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 <redacted>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dan Carpenter <redacted>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lorenzo Stoakes <redacted>
Cc: Mateusz Guzik <redacted>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pedro Falcato <redacted>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eliav Farber <redacted>
---
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