[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Matthias Fuchs]

Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
---
 board/esd/cpci405/cpci405.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/board/esd/cpci405/cpci405.c b/board/esd/cpci405/cpci405.c
index 98a8584..41b5ba0 100644
--- a/board/esd/cpci405/cpci405.c
+++ b/board/esd/cpci405/cpci405.c
@@ -656,7 +656,6 @@ int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	int i;
 	unsigned char ow_id[6];
 	char str[32];
-	unsigned char ow_crc;
 
 	/*
 	 * Clear 1-wire bit (open drain with pull-up)
@@ -675,11 +674,10 @@ int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	OWReadByte(); /* skip family code ( == 0x01) */
 	for (i = 0; i < 6; i++)
 		ow_id[i] = OWReadByte();
-	ow_crc = OWReadByte(); /* read crc */
+	OWReadByte(); /* read crc */
 
-	sprintf(str, "%08X%04X",
-		*(unsigned int *)&ow_id[0],
-		*(unsigned short *)&ow_id[4]);
+	sprintf(str, "%02X%02X%02X%02X%02X%02X",
+		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);
 	printf("Setting environment variable 'ow_id' to %s\n", str);
 	setenv("ow_id", str);
 
-- 
1.6.1

[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Marek Vasut]

> Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
> ---
>  board/esd/cpci405/cpci405.c |    8 +++-----
>  1 files changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/board/esd/cpci405/cpci405.c b/board/esd/cpci405/cpci405.c
> index 98a8584..41b5ba0 100644
> --- a/board/esd/cpci405/cpci405.c
> +++ b/board/esd/cpci405/cpci405.c
> @@ -656,7 +656,6 @@ int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc,
> char * const argv[]) int i;
>  	unsigned char ow_id[6];
>  	char str[32];
> -	unsigned char ow_crc;
> 
>  	/*
>  	 * Clear 1-wire bit (open drain with pull-up)
> @@ -675,11 +674,10 @@ int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc,
> char * const argv[]) OWReadByte(); /* skip family code ( == 0x01) */
>  	for (i = 0; i < 6; i++)
>  		ow_id[i] = OWReadByte();
> -	ow_crc = OWReadByte(); /* read crc */
> +	OWReadByte(); /* read crc */

Are you sure this doesn't get optimized out? Did you test this patch please?
> 
> -	sprintf(str, "%08X%04X",
> -		*(unsigned int *)&ow_id[0],
> -		*(unsigned short *)&ow_id[4]);
> +	sprintf(str, "%02X%02X%02X%02X%02X%02X",
> +		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);
>  	printf("Setting environment variable 'ow_id' to %s\n", str);
>  	setenv("ow_id", str);

This does indeed look eerie, the old code.

Ok, good, I'll assign this gcc4.6 thing to myself and start picking these.

[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Mike Frysinger]

On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
> -	sprintf(str, "%08X%04X",
> -		*(unsigned int *)&ow_id[0],
> -		*(unsigned short *)&ow_id[4]);
> +	sprintf(str, "%02X%02X%02X%02X%02X%02X",
> +		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);

use __get_unaligned_le32 and __get_unaligned_le16 helpers to avoid having to 
decode each byte.
-mike
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[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Marek Vasut]

> On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
> > -	sprintf(str, "%08X%04X",
> > -		*(unsigned int *)&ow_id[0],
> > -		*(unsigned short *)&ow_id[4]);
> > +	sprintf(str, "%02X%02X%02X%02X%02X%02X",
> > +		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);
> 
> use __get_unaligned_le32 and __get_unaligned_le16 helpers to avoid having
> to decode each byte.
> -mike

Is there any overhead introduced ?

M

[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Matthias Fuchs]

On 11/24/2011 06:40 PM, Mike Frysinger wrote:
> On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
>> -	sprintf(str, "%08X%04X",
>> -		*(unsigned int *)&ow_id[0],
>> -		*(unsigned short *)&ow_id[4]);
>> +	sprintf(str, "%02X%02X%02X%02X%02X%02X",
>> +		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);
> 
> use __get_unaligned_le32 and __get_unaligned_le16 helpers to avoid having to 
> decode each byte.
I must admit that I like the new style much more. But thanks for the hint on the
__get-unaligned macros :-)

Matthias

[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Mike Frysinger]

On Friday 25 November 2011 03:33:39 Marek Vasut wrote:
> > On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
> > > -	sprintf(str, "%08X%04X",
> > > -		*(unsigned int *)&ow_id[0],
> > > -		*(unsigned short *)&ow_id[4]);
> > > +	sprintf(str, "%02X%02X%02X%02X%02X%02X",
> > > +		ow_id[0], ow_id[1], ow_id[2], ow_id[3], ow_id[4], ow_id[5]);
> > 
> > use __get_unaligned_le32 and __get_unaligned_le16 helpers to avoid having
> > to decode each byte.
> 
> Is there any overhead introduced ?

i imagine get_unaligned will be as worse as indexing every byte (which is what 
Matthias is proposing we change to), or as good as the current code (just 
casting the data).  depends on the arch.
-mike
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[U-Boot] [PATCH] board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

[Wolfgang Denk]

Dear Matthias Fuchs,

In message <4ECE6529.8050307@esd.eu> you wrote:
> Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
> ---
>  board/esd/cpci405/cpci405.c |    8 +++-----
>  1 files changed, 3 insertions(+), 5 deletions(-)

Applied, thanks.

Stefan, hope this is OK with you, but I want to get rid of these
warnings.

Best regards,

Wolfgang Denk

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