I'm not sure if we're breaking some aliasing rule here, but with gcc
12.2.1 on x86_64 and -flto, the siphash_20b() call in tcp_hash()
doesn't see the connection address -- it gets all zeroes instead.
Fix this temporarily by disabling optimisations for this tcp_hash().
Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com>
---
tcp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tcp.c b/tcp.c
index 81468d9..803c2c4 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1185,6 +1185,9 @@ static int tcp_hash_match(const struct tcp_tap_conn *conn,
#if TCP_HASH_NOINLINE
__attribute__((__noinline__)) /* See comment in Makefile */
#endif
+__attribute__((optimize("O0"))) /* TODO: with -O2 and -flto on gcc 12.2,
+ * siphash_20b() doesn't see 'addr', why?
+ */
static unsigned int tcp_hash(const struct ctx *c, const union inany_addr *addr,
in_port_t tap_port, in_port_t sock_port)
{
--
2.39.1