dhcpv6: fix GCC error (unterminated-string-initialization)

The string STR_NOTONLINK is intentionally not NUL-terminated.
Ignore the GCC error using __attribute__((nonstring)).

This error is reported by GCC 15.1.1 on Fedora 42. However,
Clang 20.1.3 does not support __attribute__((nonstring)).
Therefore, NOLINTNEXTLINE(clang-diagnostic-unknown-attributes)
is also added to suppress Clang's unknown attribute warning.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/dhcpv6.c b/dhcpv6.c
index 373a988..ba16c66 100644
--- a/dhcpv6.c
+++ b/dhcpv6.c
@@ -144,7 +144,9 @@ struct opt_ia_addr {
 struct opt_status_code {
 	struct opt_hdr hdr;
 	uint16_t code;
-	char status_msg[sizeof(STR_NOTONLINK) - 1];
+	/* "nonstring" is only supported since clang 23 */
+	/* NOLINTNEXTLINE(clang-diagnostic-unknown-attributes) */
+	__attribute__((nonstring)) char status_msg[sizeof(STR_NOTONLINK) - 1];
 } __attribute__((packed));
 
 /**