Re: [PATCH][RFC] err.h: silence sparse warning: dereference of noderef expression

[Jeff Layton]

On Wed, 11 Jun 2014 08:45:18 +0300
Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:

> On Tue, Jun 10, 2014 at 05:38:49PM -0400, Jeff Layton wrote:
> > From: Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
> > 
> > Lately, when I do a make with C=1, I get *tons* of these warnings:
> > 
> >     include/linux/err.h:35:16: warning: dereference of noderef expression
> >     include/linux/err.h:30:23: warning: dereference of noderef expression
> 
> Which version of Sparse, which version of the kernel and which .c file
> can I compile to reproduce this?
> 
> I built fs/cifs/ and I didn't see the sparse warning.
> 
> regards,
> dan carpenter
> 

$ rpm -q sparse
sparse-0.5.0-1.fc20.x86_64

I see it all over the tree, but an easy example is fs/locks.c:

$ make fs/locks.o C=1
make[1]: Nothing to be done for `all'.
make[1]: Nothing to be done for `relocs'.
  CHK     include/config/kernel.release
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CALL    scripts/checksyscalls.sh
  CHECK   fs/locks.c
include/linux/err.h:35:16: warning: dereference of noderef expression
include/linux/err.h:30:23: warning: dereference of noderef expression
include/linux/err.h:35:16: warning: dereference of noderef expression
include/linux/err.h:30:23: warning: dereference of noderef expression
  CC      fs/locks.o

It has two IS_ERR calls and two PTR_ERR calls, and each generates the
warning.

-- 
Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/