On Mon, Oct 18, 2021 at 12:31 PM Nathan Chancellor <nathan@xxxxxxxxxx> wrote: > > A new warning in clang points out two places in this driver where > boolean expressions are being used with a bitwise OR instead of a > logical one: > > drivers/net/ethernet/netronome/nfp/nfp_asm.c:199:20: error: use of bitwise '|' with boolean operands [-Werror,-Wbitwise-instead-of-logical] > reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > || > drivers/net/ethernet/netronome/nfp/nfp_asm.c:199:20: note: cast one or both operands to int to silence this warning > drivers/net/ethernet/netronome/nfp/nfp_asm.c:280:20: error: use of bitwise '|' with boolean operands [-Werror,-Wbitwise-instead-of-logical] > reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > || > drivers/net/ethernet/netronome/nfp/nfp_asm.c:280:20: note: cast one or both operands to int to silence this warning > 2 errors generated. > > The motivation for the warning is that logical operations short circuit > while bitwise operations do not. In this case, it does not seem like > short circuiting is harmful so implement the suggested fix of changing > to a logical operation to fix the warning. I agree. Thanks for the patch. Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > Link: https://github.com/ClangBuiltLinux/linux/issues/1479 > Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> > --- > drivers/net/ethernet/netronome/nfp/nfp_asm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/netronome/nfp/nfp_asm.c b/drivers/net/ethernet/netronome/nfp/nfp_asm.c > index 2643ea5948f4..154399c5453f 100644 > --- a/drivers/net/ethernet/netronome/nfp/nfp_asm.c > +++ b/drivers/net/ethernet/netronome/nfp/nfp_asm.c > @@ -196,7 +196,7 @@ int swreg_to_unrestricted(swreg dst, swreg lreg, swreg rreg, > } > > reg->dst_lmextn = swreg_lmextn(dst); > - reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg); > + reg->src_lmextn = swreg_lmextn(lreg) || swreg_lmextn(rreg); > > return 0; > } > @@ -277,7 +277,7 @@ int swreg_to_restricted(swreg dst, swreg lreg, swreg rreg, > } > > reg->dst_lmextn = swreg_lmextn(dst); > - reg->src_lmextn = swreg_lmextn(lreg) | swreg_lmextn(rreg); > + reg->src_lmextn = swreg_lmextn(lreg) || swreg_lmextn(rreg); > > return 0; > } > > base-commit: 041c61488236a5a84789083e3d9f0a51139b6edf > -- > 2.33.1.637.gf443b226ca > > -- Thanks, ~Nick Desaulniers
