| Message ID | 1385048986-14478-1-git-send-email-bp@alien8.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Nov 21, 2013 at 4:49 PM, Borislav Petkov <bp@alien8.de> wrote: > From: Borislav Petkov <bp@suse.de> > > gcc complains that: > > drivers/gpu/drm/i915/i915_debugfs.c: In function ‘display_crc_ctl_write’: > drivers/gpu/drm/i915/i915_debugfs.c:2393:2: warning: ‘val’ may be used uninitialized in this function [-Wuninitialized] > drivers/gpu/drm/i915/i915_debugfs.c:2350:6: note: ‘val’ was declared here > > but it can't see that we're going to use val only in the success case. > So shut it up. > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: David Airlie <airlied@linux.ie> > Cc: intel-gfx@lists.freedesktop.org > Cc: dri-devel@lists.freedesktop.org > Signed-off-by: Borislav Petkov <bp@suse.de> > --- > drivers/gpu/drm/i915/i915_debugfs.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > index 6ed45a984230..1191aa47adc9 100644 > --- a/drivers/gpu/drm/i915/i915_debugfs.c > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > @@ -2347,7 +2347,7 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe, > { > struct drm_i915_private *dev_priv = dev->dev_private; > struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; > - u32 val; > + u32 val = 0; /* shut up gcc */ Wouldn't it be better to use uninitialized_var() here? > int ret; > > if (pipe_crc->source == source) > -- > 1.8.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
On Thu, Nov 21, 2013 at 05:10:30PM +0100, Richard Weinberger wrote: > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > > index 6ed45a984230..1191aa47adc9 100644 > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > @@ -2347,7 +2347,7 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe, > > { > > struct drm_i915_private *dev_priv = dev->dev_private; > > struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; > > - u32 val; > > + u32 val = 0; /* shut up gcc */ > > Wouldn't it be better to use uninitialized_var() here? I remember Linus' rant about this macro so that's why I don't use it anymore. In this specific case, it doesn't matter whichever we do so I'll let the maintainer make a wish :)
On Thu, Nov 21, 2013 at 04:49:46PM +0100, Borislav Petkov wrote: > From: Borislav Petkov <bp@suse.de> > > gcc complains that: > > drivers/gpu/drm/i915/i915_debugfs.c: In function ‘display_crc_ctl_write’: > drivers/gpu/drm/i915/i915_debugfs.c:2393:2: warning: ‘val’ may be used uninitialized in this function [-Wuninitialized] > drivers/gpu/drm/i915/i915_debugfs.c:2350:6: note: ‘val’ was declared here > > but it can't see that we're going to use val only in the success case. > So shut it up. > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: David Airlie <airlied@linux.ie> > Cc: intel-gfx@lists.freedesktop.org > Cc: dri-devel@lists.freedesktop.org > Signed-off-by: Borislav Petkov <bp@suse.de> Queued for -next, thanks for the patch. -Daniel > --- > drivers/gpu/drm/i915/i915_debugfs.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > index 6ed45a984230..1191aa47adc9 100644 > --- a/drivers/gpu/drm/i915/i915_debugfs.c > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > @@ -2347,7 +2347,7 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe, > { > struct drm_i915_private *dev_priv = dev->dev_private; > struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; > - u32 val; > + u32 val = 0; /* shut up gcc */ > int ret; > > if (pipe_crc->source == source) > -- > 1.8.4 >
On Thu, Nov 21, 2013 at 05:25:35PM +0100, Borislav Petkov wrote: > On Thu, Nov 21, 2013 at 05:10:30PM +0100, Richard Weinberger wrote: > > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > > > index 6ed45a984230..1191aa47adc9 100644 > > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > > @@ -2347,7 +2347,7 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe, > > > { > > > struct drm_i915_private *dev_priv = dev->dev_private; > > > struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; > > > - u32 val; > > > + u32 val = 0; /* shut up gcc */ > > > > Wouldn't it be better to use uninitialized_var() here? > > I remember Linus' rant about this macro so that's why I don't use it > anymore. > > In this specific case, it doesn't matter whichever we do so I'll let the > maintainer make a wish :) IIRC this warning was there for me too on gcc 4.6, but it disappeared on gcc 4.7, which is why I decided not to send a patch for it.
On Fri, Nov 22, 2013 at 05:09:59PM +0200, Ville Syrjälä wrote: > IIRC this warning was there for me too on gcc 4.6, but it disappeared > on gcc 4.7, which is why I decided not to send a patch for it. A disappearing and reappearing warning happened to me recently too. I attributed that to compiler upgrades. With this it will shut up for good. :-)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 6ed45a984230..1191aa47adc9 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2347,7 +2347,7 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe, { struct drm_i915_private *dev_priv = dev->dev_private; struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; - u32 val; + u32 val = 0; /* shut up gcc */ int ret; if (pipe_crc->source == source)