[PATCH] lscpu: fix possibly undefined operation

[PATCH] lscpu: fix possibly undefined operation

[Petr Uzel]

With -Wall -Werror, compilation of lscpu.c fails with:

  Making all in sys-utils
  make[2]: Entering directory `/home/petr/upstream/util-linux/sys-utils'
  gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I..  -include ../config.h -I../include -DLOCALEDIR=\"/usr/share/locale\"  -fsigned-char -Wall -Werror -MT lscpu.o -MD -MP -MF .deps/lscpu.Tpo -c -o lscpu.o lscpu.c
  lscpu.c: In function ‘print_parsable’:
  lscpu.c:971:7: error: operation on ‘p’ may be undefined [-Werror=sequence-point]
  cc1: all warnings being treated as errors

Fix by splitting the pointer increment to separate statement.

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
---
 sys-utils/lscpu.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c
index 1c2d9b6..f4a06e6 100644
--- a/sys-utils/lscpu.c
+++ b/sys-utils/lscpu.c
@@ -967,8 +967,10 @@ print_parsable(struct lscpu_desc *desc, int cols[], int ncols,
 			 */
 			char *p = data + 1;
 
-			while (p && *p != '\0')
-				*p++ = tolower((unsigned int) *p);
+			while (p && *p != '\0') {
+				*p = tolower((unsigned int) *p);
+				p++;
+			}
 		}
 		fputs(data && *data ? data : "", stdout);
 	}
-- 
1.7.7

Re: [PATCH] lscpu: fix possibly undefined operation

[Karel Zak]

On Mon, Apr 23, 2012 at 10:43:38AM +0200, Petr Uzel wrote:
>  sys-utils/lscpu.c |    6 ++++--
>  1 files changed, 4 insertions(+), 2 deletions(-)

 Applied, thanks.

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com