fix: compilation error when attachment is off

include/zenoh-pico/api/primitives.h

@@ -526,6 +526,7 @@ z_bytes_t z_query_parameters(const z_query_t *query);
  */
 z_value_t z_query_value(const z_query_t *query);
 
+#if Z_FEATURE_ATTACHMENT == 1
 /**
  * Get a query's attachment value by aliasing it.
  * Note: This API has been marked as unstable: it works as advertised, but we may change it in a future release.
@@ -537,6 +538,7 @@ z_value_t z_query_value(const z_query_t *query);
  *   Returns the attachment wrapped as a :c:type:`z_attachment_t`, since attachment is a user-defined representation.
  */
 z_attachment_t z_query_attachment(const z_query_t *query);
+#endif
 
 /**
  * Get a query's key by aliasing it.

src/api/api.c

@@ -298,7 +298,9 @@ z_bytes_t z_query_parameters(const z_query_t *query) {
 
 z_value_t z_query_value(const z_query_t *query) { return query->_val._rc.in->val._value; }
 
+#if Z_FEATURE_ATTACHMENT == 1
 z_attachment_t z_query_attachment(const z_query_t *query) { return query->_val._rc.in->val.attachment; }
+#endif
 
 z_keyexpr_t z_query_keyexpr(const z_query_t *query) { return query->_val._rc.in->val._key; }
 

src/session/subscription.c

@@ -192,7 +192,9 @@ int8_t _z_trigger_subscriptions(_z_session_t *zn, const _z_keyexpr_t keyexpr, co
             sub->in->val._callback(&s, sub->in->val._arg);
             xs = _z_subscription_rc_list_tail(xs);
         }
+#if Z_FEEATURE_ATTACHMENT == 1
         _z_attachment_drop(&s.attachment);
+#endif
         _z_keyexpr_clear(&key);
         _z_subscription_rc_list_free(&subs);
     } else {