Re: [dpdk-dev] [PATCH] net/cxgbe: fix build with clang 3.4.2

[Raslan Darawsheh <rasland@mellanox.com>]

Hi,
> -----Original Message-----
> From: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
> Sent: Wednesday, March 18, 2020 3:48 PM
> To: Ferruh Yigit <ferruh.yigit@intel.com>
> Cc: Karra Satwik <kaara.satwik@chelsio.com>; dev@dpdk.org; Raslan
> Darawsheh <rasland@mellanox.com>; Xueming Zhang
> <xuemingx.zhang@intel.com>
> Subject: Re: [PATCH] net/cxgbe: fix build with clang 3.4.2
> 
> On Wednesday, March 03/18/20, 2020 at 12:52:36 +0000, Ferruh Yigit wrote:
> > Build error:
> > .../drivers/net/cxgbe/cxgbe_flow.c:315:2:
> >     error: implicit truncation from 'int' to bitfield changes value
> >     from -1 to 7 [-Werror,-Wbitfield-constant-conversion]
> >         CXGBE_FILL_FS(adap->pf, ~0, pf);
> >         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > .../drivers/net/cxgbe/cxgbe_flow.c:25:2:
> >     note: expanded from macro 'CXGBE_FILL_FS'
> >         __CXGBE_FILL_FS(v, m, fs, elem, e)
> >         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > .../drivers/net/cxgbe/cxgbe_flow.c:15:18: note:
> >     expanded from macro '__CXGBE_FILL_FS'
> >         (fs)->mask.elem = (__m); \
> >                         ^ ~~~~~
> > Commit in fixes line changes 'PF_BITWIDTH' to '3', which makes 'fs->pf'
> > bitfield size '3', changing '~0' to '0x7' to prevent truncation in
> > assignment.
> >
> > Fixes: dcd456abe46f ("net/cxgbe: support flow API for matching all packets
> on PF")
> >
> > Reported-by: Raslan Darawsheh <rasland@mellanox.com>
> > Reported-by: Xueming Zhang <xuemingx.zhang@intel.com>
> > Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> 
> I've tested CLANG compilation with 9.0.1 without this patch,
> but couldn't hit the above mentioned error.
> 
> # clang --version
> clang version 9.0.1 (Fedora 9.0.1-2.fc31)
> 
> However, after grabbing CLANG 3.4.2, I could see the error.
> 
> # clang --version
> clang version 3.4.2 (tags/RELEASE_34/dot2-final)
> 
> This patch fixes it and the fix is correct too.
> 
> Thanks for fixing it.
> 
Working just fine for me as well, thanks for the update
Tested-by:  Raslan Darawsheh <rasland@mellanox.com>

> Acked-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
> 
> > ---
> > Cc: kaara.satwik@chelsio.com
> > ---
> >  drivers/net/cxgbe/cxgbe_flow.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/cxgbe/cxgbe_flow.c
> b/drivers/net/cxgbe/cxgbe_flow.c
> > index 13fd78aaf..a46515d3b 100644
> > --- a/drivers/net/cxgbe/cxgbe_flow.c
> > +++ b/drivers/net/cxgbe/cxgbe_flow.c
> > @@ -312,7 +312,7 @@ ch_rte_parsetype_pf(const void *dmask
> __rte_unused,
> >
> >  	CXGBE_FILL_FS(1, 1, pfvf_vld);
> >
> > -	CXGBE_FILL_FS(adap->pf, ~0, pf);
> > +	CXGBE_FILL_FS(adap->pf, 0x7, pf);
> >  	return 0;
> >  }
> >
> > --
> > 2.25.1
> >