[PATCH 2/2] include: warn for inconsistent endian config definition

From: Babu Moger
Date: Thu Jun 08 2017 - 18:19:07 EST


Display warning if CPU_BIG_ENDIAN is not defined on big endian
architecture and also warn if it defined on little endian architectures.

We have seen some generic code(for example code include/asm-generic/qrwlock.h)
uses CONFIG_CPU_BIG_ENDIAN to decide the endianess.

Here is the original discussion
http://www.spinics.net/lists/devicetree/msg178101.html

Signed-off-by: Babu Moger <babu.moger@xxxxxxxxxx>
Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
---
include/linux/byteorder/big_endian.h | 4 ++++
include/linux/byteorder/little_endian.h | 4 ++++
2 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/include/linux/byteorder/big_endian.h b/include/linux/byteorder/big_endian.h
index 3920414..ffd2159 100644
--- a/include/linux/byteorder/big_endian.h
+++ b/include/linux/byteorder/big_endian.h
@@ -3,5 +3,9 @@

#include <uapi/linux/byteorder/big_endian.h>

+#ifndef CONFIG_CPU_BIG_ENDIAN
+#warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN
+#endif
+
#include <linux/byteorder/generic.h>
#endif /* _LINUX_BYTEORDER_BIG_ENDIAN_H */
diff --git a/include/linux/byteorder/little_endian.h b/include/linux/byteorder/little_endian.h
index 0805737..ba910bb 100644
--- a/include/linux/byteorder/little_endian.h
+++ b/include/linux/byteorder/little_endian.h
@@ -3,5 +3,9 @@

#include <uapi/linux/byteorder/little_endian.h>

+#ifdef CONFIG_CPU_BIG_ENDIAN
+#warning inconsistent configuration, CONFIG_CPU_BIG_ENDIAN is set
+#endif
+
#include <linux/byteorder/generic.h>
#endif /* _LINUX_BYTEORDER_LITTLE_ENDIAN_H */
--
1.7.1