On Wed, Oct 03, 2018 at 03:53:58PM -0700, Nick Desaulniers wrote: > On Wed, Oct 3, 2018 at 3:35 PM Jason Gunthorpe <jgg@xxxxxxxx> wrote: > > > > On Mon, Sep 24, 2018 at 12:57:16PM -0700, Nathan Chancellor wrote: > > > Clang warns when one enumerated type is implicitly converted to another. > > > > > > drivers/infiniband/hw/mlx4/mad.c:1811:41: warning: implicit conversion > > > from enumeration type 'enum mlx4_ib_qp_flags' to different enumeration > > > type 'enum ib_qp_create_flags' [-Wenum-conversion] > > > qp_init_attr.init_attr.create_flags = MLX4_IB_SRIOV_TUNNEL_QP; > > > ~ ^~~~~~~~~~~~~~~~~~~~~~~ > > > > > > drivers/infiniband/hw/mlx4/mad.c:1819:41: warning: implicit conversion > > > from enumeration type 'enum mlx4_ib_qp_flags' to different enumeration > > > type 'enum ib_qp_create_flags' [-Wenum-conversion] > > > qp_init_attr.init_attr.create_flags = MLX4_IB_SRIOV_SQP; > > > ~ ^~~~~~~~~~~~~~~~~ > > > > > > The type mlx4_ib_qp_flags explicitly provides supplemental values to the > > > type ib_qp_create_flags. Make that clear to Clang by changing the > > > create_flags type to u32. > > > > > > Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > > Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > > > include/rdma/ib_verbs.h | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > Applied to for-next, thanks > > > > BTW, how are you compiling with clang? > > https://github.com/ClangBuiltLinux/linux/wiki/Steps-for-compiling-the-kernel-with-Clang > try it out, let us know bugs you find here: > https://github.com/ClangBuiltLinux/linux/issues Oh I see, you are doing ARM64! > Still looking into the case you pointed out earlier. I suspect the > signedness of enums was undefined in c90, then defined as > implementation specific in c99 (though I'm still researching that > book report). Thanks for your insights! C enums details are a topic that seems more confusing every time it gets brought up :( Jason
