[PATCH 3.12 042/127] ARM: 8584/1: floppy: avoid gcc-6 warning

From	Jiri Slaby <jslaby@suse.cz>
Newsgroups	linux.kernel
Subject	[PATCH 3.12 042/127] ARM: 8584/1: floppy: avoid gcc-6 warning
Date	2016-11-25 10:00 +0100
Message-ID	<sHkwp-6MV-5@gated-at.bofh.it> (permalink)
References	<sHkd3-6Ft-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

From: Arnd Bergmann <arnd@arndb.de>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit dd665be0e243873343a28e18f9f345927b658daf upstream.

gcc-6.0 warns about comparisons between two identical expressions,
which is what we get in the floppy driver when writing to the FD_DOR
register:

drivers/block/floppy.c: In function 'set_dor':
drivers/block/floppy.c:810:44: error: self-comparison always evaluates to true [-Werror=tautological-compare]
   fd_outb(newdor, FD_DOR);

It would be nice to use a static inline function instead of the
macro, to avoid the warning, but we cannot do that because the
FD_DOR definition is incomplete at this point.

Adding a cast to (u32) is a harmless way to shut up the warning,
just not very nice.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 arch/arm/include/asm/floppy.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/floppy.h b/arch/arm/include/asm/floppy.h
index c9f03eccc9d8..b5a0466db549 100644
--- a/arch/arm/include/asm/floppy.h
+++ b/arch/arm/include/asm/floppy.h
@@ -17,7 +17,7 @@
 
 #define fd_outb(val,port)			\
 	do {					\
-		if ((port) == FD_DOR)		\
+		if ((port) == (u32)FD_DOR)	\
 			fd_setdor((val));	\
 		else				\
 			outb((val),(port));	\
-- 
2.10.2

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH 3.12 042/127] ARM: 8584/1: floppy: avoid gcc-6 warning Jiri Slaby <jslaby@suse.cz> - 2016-11-25 10:00 +0100

csiph-web