[alsa-devel] [patch] sound/usb/format: silence uninitialized variable warnings
Gcc complains that ret might be used uninitialized:
sound/usb/format.c: In function ‘snd_usb_parse_audio_format’: sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:354: note: ‘ret’ was declared here sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:414: note: ‘ret’ was declared here
I suppose it could be if there is ever a UAC_VERSION_3 released. Anyway this patch is worthwhile if only to silence the gcc warning.
Signed-off-by: Dan Carpenter error27@gmail.com
diff --git a/sound/usb/format.c b/sound/usb/format.c index 4387f54..1400174 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -351,7 +351,8 @@ static int parse_audio_format_i(struct snd_usb_audio *chip, { struct usb_interface_descriptor *altsd = get_iface_desc(iface); int protocol = altsd->bInterfaceProtocol; - int pcm_format, ret; + int pcm_format; + int ret = -EINVAL;
if (fmt->bFormatType == UAC_FORMAT_TYPE_III) { /* FIXME: the format type is really IECxxx @@ -411,9 +412,10 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, int format, void *_fmt, struct usb_host_interface *iface) { - int brate, framesize, ret; + int brate, framesize; struct usb_interface_descriptor *altsd = get_iface_desc(iface); int protocol = altsd->bInterfaceProtocol; + int ret = -EINVAL;
switch (format) { case UAC_FORMAT_TYPE_II_AC3:
At Sat, 14 Aug 2010 10:58:47 +0200, Dan Carpenter wrote:
Gcc complains that ret might be used uninitialized:
sound/usb/format.c: In function ‘snd_usb_parse_audio_format’: sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:354: note: ‘ret’ was declared here sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:414: note: ‘ret’ was declared here
I suppose it could be if there is ever a UAC_VERSION_3 released. Anyway this patch is worthwhile if only to silence the gcc warning.
It's nice to catch such possible bugs. But, it'd be even nicer if kernel gives messages what's wrong instead of silent break-up. Could you add error messages and repost the revised patch?
thanks,
Takashi
Signed-off-by: Dan Carpenter error27@gmail.com
diff --git a/sound/usb/format.c b/sound/usb/format.c index 4387f54..1400174 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -351,7 +351,8 @@ static int parse_audio_format_i(struct snd_usb_audio *chip, { struct usb_interface_descriptor *altsd = get_iface_desc(iface); int protocol = altsd->bInterfaceProtocol;
- int pcm_format, ret;
int pcm_format;
int ret = -EINVAL;
if (fmt->bFormatType == UAC_FORMAT_TYPE_III) { /* FIXME: the format type is really IECxxx
@@ -411,9 +412,10 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, int format, void *_fmt, struct usb_host_interface *iface) {
- int brate, framesize, ret;
int brate, framesize; struct usb_interface_descriptor *altsd = get_iface_desc(iface); int protocol = altsd->bInterfaceProtocol;
int ret = -EINVAL;
switch (format) { case UAC_FORMAT_TYPE_II_AC3:
Gcc complains that ret might be used uninitialized:
sound/usb/format.c: In function ‘snd_usb_parse_audio_format’: sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:354: note: ‘ret’ was declared here sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:414: note: ‘ret’ was declared here
I suppose it could be uninitialized if there is ever a UAC_VERSION_3 released. Anyway this patch is worthwhile if only to silence the gcc warning.
Signed-off-by: Dan Carpenter error27@gmail.com --- V2: Totally different. Added printk()s
diff --git a/sound/usb/format.c b/sound/usb/format.c index 4387f54..3a13754 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -392,6 +392,10 @@ static int parse_audio_format_i(struct snd_usb_audio *chip, /* fp->channels is already set in this case */ ret = parse_audio_format_rates_v2(chip, fp); break; + default: + snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n", + chip->dev->devnum, fp->iface, fp->altsetting, protocol); + return -EINVAL; }
if (fp->channels < 1) { @@ -452,6 +456,10 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, ret = parse_audio_format_rates_v2(chip, fp); break; } + default: + snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n", + chip->dev->devnum, fp->iface, fp->altsetting, protocol); + return -EINVAL; }
return ret;
On Sat, Aug 14, 2010 at 07:29:53PM +0200, Dan Carpenter wrote:
Gcc complains that ret might be used uninitialized:
sound/usb/format.c: In function ‘snd_usb_parse_audio_format’: sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:354: note: ‘ret’ was declared here sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:414: note: ‘ret’ was declared here
I suppose it could be uninitialized if there is ever a UAC_VERSION_3 released. Anyway this patch is worthwhile if only to silence the gcc warning.
Signed-off-by: Dan Carpenter error27@gmail.com
Yes, such a check can't harm. You can have my
Acked-by: Daniel Mack daniel@caiaq.de
if you want :)
Thanks, Daniel
V2: Totally different. Added printk()s
diff --git a/sound/usb/format.c b/sound/usb/format.c index 4387f54..3a13754 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -392,6 +392,10 @@ static int parse_audio_format_i(struct snd_usb_audio *chip, /* fp->channels is already set in this case */ ret = parse_audio_format_rates_v2(chip, fp); break;
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",chip->dev->devnum, fp->iface, fp->altsetting, protocol);return -EINVAL;}
if (fp->channels < 1) {
@@ -452,6 +456,10 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, ret = parse_audio_format_rates_v2(chip, fp); break; }
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",chip->dev->devnum, fp->iface, fp->altsetting, protocol);return -EINVAL;}
return ret;
At Sat, 14 Aug 2010 19:29:53 +0200, Dan Carpenter wrote:
Gcc complains that ret might be used uninitialized:
sound/usb/format.c: In function ‘snd_usb_parse_audio_format’: sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:354: note: ‘ret’ was declared here sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function sound/usb/format.c:414: note: ‘ret’ was declared here
I suppose it could be uninitialized if there is ever a UAC_VERSION_3 released. Anyway this patch is worthwhile if only to silence the gcc warning.
Signed-off-by: Dan Carpenter error27@gmail.com
V2: Totally different. Added printk()s
Thanks, applied now.
Takashi
diff --git a/sound/usb/format.c b/sound/usb/format.c index 4387f54..3a13754 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -392,6 +392,10 @@ static int parse_audio_format_i(struct snd_usb_audio *chip, /* fp->channels is already set in this case */ ret = parse_audio_format_rates_v2(chip, fp); break;
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",chip->dev->devnum, fp->iface, fp->altsetting, protocol);return -EINVAL;}
if (fp->channels < 1) {
@@ -452,6 +456,10 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, ret = parse_audio_format_rates_v2(chip, fp); break; }
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",chip->dev->devnum, fp->iface, fp->altsetting, protocol);return -EINVAL;}
return ret;
participants (3)
-
Dan Carpenter -
Daniel Mack -
Takashi Iwai