[PATCH 1/1] [PATCH] udhcp: Fixed aliasing compilation error and alignment issues.

[Martin Lewis]

Fixed the compilation warning:
networking/udhcp/d6_common.h:146:99: warning: dereferencing type-punned pointer 
will break strict-aliasing rules [-Wstrict-aliasing]
 #define client6_data (*(struct 
client6_data_t*)(&bb_common_bufsiz1[COMMON_BUFSIZE - sizeof(struct 
client6_data_t)]))
                                                                                
                   ^
Also fixed a possible alignment issue related to strict aliasing.

Signed-off-by: Martin Lewis <martin.lewis....@gmail.com>
---
 networking/udhcp/d6_common.h | 2 +-
 networking/udhcp/d6_dhcpc.c  | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/networking/udhcp/d6_common.h b/networking/udhcp/d6_common.h
index 2178cb9..dee2558 100644
--- a/networking/udhcp/d6_common.h
+++ b/networking/udhcp/d6_common.h
@@ -141,7 +141,7 @@ struct client6_data_t {
        unsigned env_idx;
        /* link-local IPv6 address */
        struct in6_addr ll_ip6;
-};
+} FIX_ALIASING;
 
 #define client6_data (*(struct 
client6_data_t*)(&bb_common_bufsiz1[COMMON_BUFSIZE - sizeof(struct 
client6_data_t)]))
 
diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index 6cc2316..e424ce6 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -643,7 +643,7 @@ static NOINLINE int send_d6_discover(uint32_t xid, struct 
in6_addr *requested_ip
                client6_data.ia_na = xzalloc(len);
                client6_data.ia_na->code = D6_OPT_IA_NA;
                client6_data.ia_na->len = len - 4;
-               *(uint32_t*)client6_data.ia_na->data = rand(); /* IAID */
+               move_to_unaligned32(client6_data.ia_na->data, rand());
                if (requested_ipv6) {
                        struct d6_option *iaaddr = 
(void*)(client6_data.ia_na->data + 4+4+4);
                        iaaddr->code = D6_OPT_IAADDR;
@@ -661,7 +661,7 @@ static NOINLINE int send_d6_discover(uint32_t xid, struct 
in6_addr *requested_ip
                client6_data.ia_pd = xzalloc(len);
                client6_data.ia_pd->code = D6_OPT_IA_PD;
                client6_data.ia_pd->len = len - 4;
-               *(uint32_t*)client6_data.ia_pd->data = rand(); /* IAID */
+               move_to_unaligned32(client6_data.ia_pd->data, rand());
                opt_ptr = mempcpy(opt_ptr, client6_data.ia_pd, len);
        }
 
-- 
1.9.1

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