On Tue, Sep 01, 2009 at 10:25:18PM +0400, Anton Vorontsov wrote :

On Tue, Sep 01, 2009 at 08:11:41PM +0200, Wolfgang Denk wrote:

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Dear Anton Vorontsov,

In message 20090901165803.GA3668@oksana.dev.rtsoft.ru you wrote:

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This is needed so that we could use this macro for non-UBI code.

Signed-off-by: Anton Vorontsov avorontsov@ru.mvista.com

include/compiler.h | 3 +++ include/ubi_uboot.h | 4 +--- 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/compiler.h b/include/compiler.h index 272fd3c..e602cce 100644 --- a/include/compiler.h +++ b/include/compiler.h @@ -122,4 +122,7 @@ typedef unsigned int uintptr_t;

#endif

+/* compiler options */ +#define uninitialized_var(x) x = x

Please excuse my ignorance, but where and what for is such a definition useful?

It's used to avoid GCC warnings, i.e. when GCC isn't smart enough to see that some variable isn't actually used uninitialized.

~/linux-2.6$ git grep uninitialized_var drivers/ | wc -l 94

You seem to be grepping the linux source tree. The whole U-boot codebase contains only 10 of them.

We can fix the warnings by assigning some value to a variable at declaration, but the advantage of 'x = x' trick is that it doesn't generate any code.

I'm not quite sure that would be noticeable given the number of uses (I don't have any opinion as to whether we should initialize them properly, though).

Regards,

The warning is bogus, so silence it by initializing the 'ret' variable.

Signed-off-by: Anton Vorontsov avorontsov@ru.mvista.com ---

On Tue, Sep 01, 2009 at 09:27:37PM +0200, Wolfgang Denk wrote:

Dear Anton Vorontsov,

In message 20090901182518.GA17903@oksana.dev.rtsoft.ru you wrote:

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We can fix the warnings by assigning some value to a variable at declaration, but the advantage of 'x = x' trick is that it doesn't generate any code.

Argh... what a clev^H^H^H^Hdirty trick.

Thanks for the explanation.

However, in this case it seems to make sense to me to explicitly initialize the return code with zero.

Well, I don't see any advantages of this, but here it is anyway.

Thanks.

p.s. Timur, since the patch has changed, I couldn't preserve your previous Ack.

board/freescale/common/sys_eeprom.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/board/freescale/common/sys_eeprom.c b/board/freescale/common/sys_eeprom.c index c0fff68..661015e 100644 --- a/board/freescale/common/sys_eeprom.c +++ b/board/freescale/common/sys_eeprom.c @@ -204,7 +204,8 @@ static void update_crc(void) */ static int prog_eeprom(void) { - int ret, i; + int ret = 0; /* shut up gcc */ + int i; void *p; #ifdef CONFIG_SYS_EEPROM_BUS_NUM unsigned int bus;