On Thu, Aug 18, 2016 at 02:52:31PM +0800, Yuanhan Liu wrote: > On Tue, Jul 05, 2016 at 06:19:24PM +0530, Jerin Jacob wrote: > > Split out SSE instruction based virtio simple Rx > > implementation to a separate file > > > > Signed-off-by: Jerin Jacob <jerin.jacob at caviumnetworks.com> > > Hi, > > I was about to apply this set. I then did some build test and found a > weird issue: it breaks the build with clang (ubuntu 16.04). > > drivers/net/virtio/virtio_rxtx_simple_sse.c:130:2: error: cast from > 'const void *' to 'void *' drops const qualifier [-Werror,-Wcast-qual] > _mm_prefetch((const void *)rused, _MM_HINT_T0); > ^ > /usr/lib/llvm-3.8/bin/../lib/clang/3.8.0/include/xmmintrin.h:684:58: > note: expanded from macro '_mm_prefetch' > #define _mm_prefetch(a, sel) (__builtin_prefetch((void *)(a), 0, (sel))) > ^ > 1 error generated. > > Weird enough I don't see this issue before this commit: the error > line is exactly the same before and after this commit.
Yes, I looked at the pre processed output as well, it comes as same before and after this commit. > > Another note is that _mm_prefetch() is actually with different prototype > for gcc and clang. For gcc, we have: > > _mm_prefetch (const void *__P, enum _mm_hint __I) > > Any thoughts? How about replacing "_mm_prefetch((const void *)rused, _MM_HINT_T0)" with "rte_prefetch0(rused)" to have same prototype and fix the issue with clang? > > --yliu > >
