board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

PATCH New Matthias Fuchs 4 participants 7 messages Nov 24, 2011 – Dec 7, 2011

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Matthias Fuchs

author

2011-11-24 15:39 UTC #0 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

Signed-off-by Matthias Fuchs <[email protected]>

---
 board/esd/cpci405/cpci405.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

board/esd/cpci405/cpci405.c +3 -5

index 98a8584..41b5ba0 100644
@@ -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);

Signature · 1 line

1.6.1

Marek Vasut

2011-11-24 17:05 UTC #1 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

Quoted 19 lines

Signed-off-by Matthias Fuchs <[email protected]>

---
 board/esd/cpci405/cpci405.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

board/esd/cpci405/cpci405.c +0 -1

index 98a8584..41b5ba0 100644
@@ -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) */

board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 677

Quoted 4 lines

board/esd/cpci405/cpci405.c +1 -1

 	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?

board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 682

Quoted 8 lines

board/esd/cpci405/cpci405.c +2 -3

-	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.

Mike Frysinger

2011-11-24 17:40 UTC #2 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

In reply to Matthias Fuchs

board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 680

Quoted 5 lines · On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:

board/esd/cpci405/cpci405.c +2 -3

-	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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Marek Vasut

2011-11-25 08:33 UTC #3 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

Quoted 10 lines · On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:

board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 680
Quoted 5 lines
board/esd/cpci405/cpci405.c +2 -3
-	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 ?

Mike Frysinger

2011-11-25 19:56 UTC #4 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

Quoted 11 lines · On Friday 25 November 2011 03:33:39 Marek Vasut wrote:

Quoted 9 lines · On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 680
Quoted 5 lines
board/esd/cpci405/cpci405.c +2 -3
-	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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Matthias Fuchs

author

2011-11-25 12:50 UTC #5 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

In reply to Mike Frysinger

Quoted 9 lines · Mike Frysinger

board/esd/cpci405/cpci405.c int do_onewire(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) · line 680
Quoted 5 lines · On Thursday 24 November 2011 10:39:21 Matthias Fuchs wrote:
board/esd/cpci405/cpci405.c +2 -3
-	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

Wolfgang Denk

Applied

2011-12-07 20:22 UTC #6 lore raw

PATCH 1/1 board/esd/cpci405/cpci405.c: Fix GCC 4.6 warning

In reply to Matthias Fuchs

Dear Matthias Fuchs,

Quoted 4 lines · In message <[email protected]> you wrote:

Signed-off-by Matthias Fuchs <[email protected]>
---
 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

Signature · 7 lines

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