[dpdk-dev] [PATCH 5/5] f_u32: fix compiler gcc-10 compiler warning

Stephen Hemminger stephen at networkplumber.org
Sun Nov 29 18:54:37 CET 2020


With gcc-10 it complains about array subscript error.

f_u32.c: In function ‘u32_parse_opt’:
f_u32.c:1113:24: warning: array subscript 0 is outside the bounds of an interior zero-length array ‘struct tc_u32_key[0]’ [-Wzero-length-bounds]
 1113 |    hash = sel2.sel.keys[0].val & sel2.sel.keys[0].mask;
      |           ~~~~~~~~~~~~~^~~
In file included from tc_util.h:11,
                 from f_u32.c:26:
../include/uapi/linux/pkt_cls.h:253:20: note: while referencing ‘keys’
  253 |  struct tc_u32_key keys[0];
      |

This is because the keys are actually allocated in the second element
of the parent structure.

Simplest way to address the warning is to assign directly to the keys
in the containing structure.

This has always been in iproute2 (pre-git) so no Fixes.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 tc/f_u32.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tc/f_u32.c b/tc/f_u32.c
index e0a322d5a11c..2ed5254a40d5 100644
--- a/tc/f_u32.c
+++ b/tc/f_u32.c
@@ -1110,7 +1110,7 @@ static int u32_parse_opt(struct filter_util *qu, char *handle,
 				}
 				NEXT_ARG();
 			}
-			hash = sel2.sel.keys[0].val & sel2.sel.keys[0].mask;
+			hash = sel2.keys[0].val & sel2.keys[0].mask;
 			hash ^= hash >> 16;
 			hash ^= hash >> 8;
 			htid = ((hash % divisor) << 12) | (htid & 0xFFF00000);
-- 
2.29.2



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