From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shinya Kuribayashi Date: Sun, 22 Feb 2009 14:24:11 +0900 Subject: [U-Boot] MIPS: Fix GCC-4.2 'discards qualifiers from pointer target type' warnings In-Reply-To: <200901301122.05028.sr@denx.de> References: <1233121463-25530-1-git-send-email-sr@denx.de> <200901281737.36571.sr@denx.de> <4982496B.80607@necel.com> <200901301122.05028.sr@denx.de> Message-ID: <49A0E17B.9090300@ruby.dti.ne.jp> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Compiling dbau1x00 and gth2 boards with GCC-4.2, you would see new warnings like this: skuribay at ubuntu:u-boot.git$ ./MAKEALL dbau1000 Configuring for dbau1x00 board... au1x00_eth.c: In function 'au1x00_send': au1x00_eth.c:158: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type au1x00_eth.c: In function 'au1x00_recv': au1x00_eth.c:211: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type au1x00_eth.c: In function 'au1x00_init': au1x00_eth.c:252: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type au1x00_eth.c: In function 'au1x00_recv': au1x00_eth.c:211: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type au1x00_eth.c: In function 'au1x00_init': au1x00_eth.c:252: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type au1x00_eth.c: In function 'au1x00_send': au1x00_eth.c:158: warning: passing argument 1 of 'virt_to_phys' discards qualifiers from pointer target type We're passing a volatile pointer to a function which is expecting a non- volatile pointer. That's potentially dangerous, so gcc warns about it. Confirmed with ELDK 4.2 (GCC 4.2.2) and Sourcey G++ 4.2 (GCC 4.2.3). To fix this, we add a volatile attribute to the argument in question. The virt_to_phys function in Linux kernel also does the same thing. Signed-off-by: Stefan Roese Signed-off-by: Shinya Kuribayashi --- Sorry for late reply, Stefan: I think this is a reasonable fix. I believe this works for ELDK as well, of course. Walfgang: Please pick this up directly, thanks in advance. include/asm-mips/io.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/include/asm-mips/io.h b/include/asm-mips/io.h index 031186d..025012a 100644 --- a/include/asm-mips/io.h +++ b/include/asm-mips/io.h @@ -118,7 +118,7 @@ static inline void set_io_port_base(unsigned long base) * Change virtual addresses to physical addresses and vv. * These are trivial on the 1:1 Linux/MIPS mapping */ -extern inline phys_addr_t virt_to_phys(void * address) +extern inline phys_addr_t virt_to_phys(volatile void * address) { return CPHYSADDR(address); }