[PATCH v2 RESEND] ARM: fix unmet dependency on BITREVERSE for HAVE_ARCH_BITREVERSE

From: Julian Braha
Date: Sun Jan 16 2022 - 23:09:47 EST


Resending this to properly add it to the patch tracker - thanks for letting
me know, Arnd :)

When ARM is enabled, and BITREVERSE is disabled,
Kbuild gives the following warning:

WARNING: unmet direct dependencies detected for HAVE_ARCH_BITREVERSE
Depends on [n]: BITREVERSE [=n]
Selected by [y]:
- ARM [=y] && (CPU_32v7M [=n] || CPU_32v7 [=y]) && !CPU_32v6 [=n]

This is because ARM selects HAVE_ARCH_BITREVERSE
without selecting BITREVERSE, despite
HAVE_ARCH_BITREVERSE depending on BITREVERSE.

This unmet dependency bug was found by Kismet,
a static analysis tool for Kconfig. Please advise if this
is not the appropriate solution.

Signed-off-by: Julian Braha <julianbraha@xxxxxxxxx>
---
v2:
Changed this fix to remove the dependency on BITREVERSE from
HAVE_ARCH_BITREVERSE, since it isn't actually necessary.

v1 link:
https://lore.kernel.org/linux-arm-kernel/20211029203110.8343-1-julianbraha@xxxxxxxxx/

KernelVersion: v5.16-rc5

lib/Kconfig | 1 -
1 file changed, 1 deletion(-)

diff --git a/lib/Kconfig b/lib/Kconfig
index c80fde816a7e..9b5a692ce00c 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -45,7 +45,6 @@ config BITREVERSE
config HAVE_ARCH_BITREVERSE
bool
default n
- depends on BITREVERSE
help
This option enables the use of hardware bit-reversal instructions on
architectures which support such operations.
--
2.32.0