[PATCH] m32r: Fix endianness constraints

From: Geert Uytterhoeven
Date: Mon Oct 30 2017 - 07:05:14 EST


The m32r Kconfig provides both CPU_BIG_ENDIAN and CPU_LITTLE_ENDIAN
configuration options. As they are user-selectable and independent,
this allows invalid configurations:

- All m32r defconfigs build a big endian kernel, but CPU_BIG_ENDIAN is
not set, causing compiler warnings like:

include/linux/byteorder/big_endian.h:7:2: warning: #warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN [-Wcpp]
#warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN
^

- Since commit 5bdfca6435b82944 ("m32r: define CPU_BIG_ENDIAN"),
building an allmodconfig or allyesconfig enables both
CONFIG_CPU_BIG_ENDIAN and CONFIG_CPU_LITTLE_ENDIAN.
While this did get rid of the warning above, both options are
obviously mutually exclusive.

Fix this by making only CPU_LITTLE_ENDIAN configurable by the user, as
before, and by making sure exactly one of CPU_BIG_ENDIAN and
CPU_LITTLE_ENDIAN is always enabled.

Fixes: 5bdfca6435b82944 ("m32r: define CPU_BIG_ENDIAN")
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
arch/m32r/Kconfig | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index 0777f3a8a1f37d6f..6119e04f6bfd7821 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -195,8 +195,8 @@ config TIMER_DIVIDE
default "128"

config CPU_BIG_ENDIAN
- bool "Generate big endian code"
- default n
+ bool
+ default !CPU_LITTLE_ENDIAN

config CPU_LITTLE_ENDIAN
bool "Generate little endian code"
--
2.7.4