avf: fix gcc compiling warning on Arm

Initializing struct avf_ip6_psh by {0} using gcc with O2 optimize option
will trigger the -Werror=maybe-uninitialized compiling warning on Arm
because gcc compiler will think some members of the struct avf_ip6_psh
may not be initialized, which probably is a false positive in this case.
The compiling error log is shown as below. Avoid this compiling warning
by explicitly declaring the IPv6 src and dst ip in avf_ip6_psh as
ip6_address_t.

ccache /usr/lib/ccache/gcc-10 -DHAVE_FCNTL64 -DHAVE_GETCPU -DHAVE_MEMFD_CREATE -I/home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src -I. -Iinclude -I/home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/plugins -Iplugins -Iplugins/avf -Wno-address-of-packed-member -g -fPIC -Werror -Wall -march=armv8-a+crc  -O2 -fstack-protector -DFORTIFY_SOURCE=2 -fno-common  -fPIC   -DCLIB_MARCH_VARIANT=cortexa72 -march=armv8-a+crc+crypto -mtune=cortex-a72 -DCLIB_N_PREFETCHES=6 -MD -MT plugins/avf/CMakeFiles/avf_plugin_cortexa72.dir/output.c.o -MF plugins/avf/CMakeFiles/avf_plugin_cortexa72.dir/output.c.o.d -o plugins/avf/CMakeFiles/avf_plugin_cortexa72.dir/output.c.o   -c /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/plugins/avf/output.c
In file included from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/vector_funcs.h:41,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/vector.h:196,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/string.h:48,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/mem.h:49,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/vec.h:42,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/format.h:44,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/elf.h:41,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/elf_clib.h:41,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vlib/vlib.h:44,
                 from /home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/plugins/avf/output.c:18:
/home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/plugins/avf/output.c: In function ‘avf_device_class_tx_fn_cortexa72’:
/home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/vppinfra/byte_order.h:59:10: error: ‘*((void *)&psh+32)’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
   59 |   return __builtin_bswap16 (x);
      |          ^~~~~~~~~~~~~~~~~~~~~
/home/snowball/tasks/test_vpp_build/test-patch-9/vpp/src/plugins/avf/output.c:115:23: note: ‘*((void *)&psh+32)’ was declared here
  115 |    struct avf_ip6_psh psh = { 0 };
      |                       ^~~

Type: fix

Change-Id: I2684b101b07823dfacc4a56cc29d152828d0cf37
Signed-off-by: Jieqiang Wang <jieqiang.wang@arm.com>

diff --git a/src/plugins/avf/output.c b/src/plugins/avf/output.c
index cbc85b8..55a01c7 100644 (file)
--- a/src/plugins/avf/output.c
+++ b/src/plugins/avf/output.c
@@ -47,8 +47,8 @@ struct avf_ip4_psh
 
 struct avf_ip6_psh
 {
-  u32 src[4];
-  u32 dst[4];
+  ip6_address_t src;
+  ip6_address_t dst;
   u32 l4len;
   u32 proto;
 };
@@ -113,8 +113,8 @@ avf_tx_prepare_cksum (vlib_buffer_t * b, u8 is_tso)
       else
        {
          struct avf_ip6_psh psh = { 0 };
-         clib_memcpy_fast (&psh.src, &ip6->src_address, 16);
-         clib_memcpy_fast (&psh.dst, &ip6->dst_address, 16);
+         psh.src = ip6->src_address;
+         psh.dst = ip6->dst_address;
          psh.proto = clib_host_to_net_u32 ((u32) ip6->protocol);
          psh.l4len = is_tso ? 0 : ip6->payload_length;
          sum = ~ip_csum (&psh, sizeof (psh));