[Patch] Fix signedness error in drivers/media/video/vivi.c

[Patch] Fix signedness error in drivers/media/video/vivi.c

[Eric Sesterhenn]

hi,

when checking the -Wextra signedness warnings issued by gcc 4.1
I came across this one:

drivers/media/video/vivi.c:1001: warning: comparison of unsigned expression < 0 is always false

Since videobuf_reqbufs() returns negative values on errors the current
code does no real error checking since gcc removes the comparison.
This patch fixes this issue by making ret a normal, signed integer.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>

--- linux-2.6.18-rc4/drivers/media/video/vivi.c.orig	2006-08-19 18:13:45.000000000 +0200
+++ linux-2.6.18-rc4/drivers/media/video/vivi.c	2006-08-19 18:14:16.000000000 +0200
@@ -992,7 +992,8 @@ static int vidiocgmbuf (struct file *fil
 	struct vivi_fh  *fh=priv;
 	struct videobuf_queue *q=&fh->vb_vidq;
 	struct v4l2_requestbuffers req;
-	unsigned int i, ret;
+	unsigned int i;
+	int ret;
 
 	req.type   = q->type;
 	req.count  = 8;

Re: [Patch] Fix signedness error in drivers/media/video/vivi.c

[Alan Cox]

Ar Sad, 2006-08-19 am 18:19 +0200, ysgrifennodd Eric Sesterhenn:
> Since videobuf_reqbufs() returns negative values on errors the current
> code does no real error checking since gcc removes the comparison.
> This patch fixes this issue by making ret a normal, signed integer.
> 
> Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
> 

Doesn't apply to latest driver tree but the problem is still present.

Alan

Re: [Patch] Fix signedness error in drivers/media/video/vivi.c

[Mauro Carvalho Chehab]

Em Dom, 2006-08-20 às 19:25 +0100, Alan Cox escreveu:
> Ar Sad, 2006-08-19 am 18:19 +0200, ysgrifennodd Eric Sesterhenn:
> > Since videobuf_reqbufs() returns negative values on errors the current
> > code does no real error checking since gcc removes the comparison.
> > This patch fixes this issue by making ret a normal, signed integer.
> > 
> > Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
> > 
> 
> Doesn't apply to latest driver tree but the problem is still present.
Hmm... patch applied fine to v4l-dvb hg tree. 
> 
> Alan
> 
Cheers, 
Mauro.