Re: [PATCH] Removing ununsed variable int lo, hi, int data and int i from comedi/drivers/dt2814.c.

From: Luc Van Oostenryck
Date: Sun May 24 2020 - 09:58:51 EST


On Sun, May 24, 2020 at 06:19:22PM +0530, GAURAV PATHAK wrote:
> Thanks a lot for your reply.
> I am trying to run sparse on drivers/staging directory,
> but I am not getting any useful warnings.
> Steps that I did:
>
> - Referred https://www.kernel.org/doc/man-pages/linux-next.html to get
> linux-next latest tag next-20200522.
> - After that executed following commands:
> - make mrproper; make clean; make distclean
> - make defconfig
> - make menuconfig (Enabled all Staging Drivers with M)
> - make modules_prepare
> - make C=1 M=drivers/staging (Also tried individual directories
> inside staging directory e.g. make C=1 M=drivers/staging/comedi/drivers)
>
> I am not getting any warning, I have attached the output in text format.
>
> Any pointers for finding warning using sparse in drivers/staging
> directory will be helpful. I really appretiate your guidance in this
> regard.

Well it seems that most staging drivers have no sparse warnings at all.
I only see somes in the following staging drivers:
drivers/staging/isdn/
drivers/staging/kpc2000/
drivers/staging/uwb/
drivers/staging/vc04_services/
drivers/staging/wfx/
drivers/staging/wusbcore/

Your commands seems to be good but I would advice you to use 'C=2'
instead of 'C=1' in order for sparse to effectively run on each
input file even when the corresponding .o file already exists.

The simplest to use is:
- make allmodconfig
- make -j8 drivers/staging/
This will just compile all the files without running sparse.
So all warnings will be from the compiler.
The you can run:
- make C=2 drivers/staging/
which will only run sparse (and will thus be much faster).

Best regards,
-- Luc