mq_timedreceive() move the location where the errno value is set; the TIMEDOUT errno setting was being overwritten by subsequent actions before returning. Noted by Freddie Chopin.

sched/mqueue/mq_timedreceive.c

@@ -258,11 +258,13 @@ ssize_t mq_timedreceive(mqd_t mqdes, FAR char *msg, size_t msglen,
 
       if (result != OK)
         {
-          set_errno(result);
           irqrestore(saved_state);
           sched_unlock();
+
           wd_delete(rtcb->waitdog);
           rtcb->waitdog = NULL;
+
+          set_errno(result);
           return ERROR;
         }
 

sched/mqueue/mq_timedsend.c

@@ -351,7 +351,8 @@ errout_with_irqsave:
 
 errout_with_mqmsg:
   mq_msgfree(mqmsg);
-  set_errno(result);
   sched_unlock();
+
+  set_errno(result);
   return ERROR;
 }

sched/mqueue/mq_waitirq.c

@@ -143,4 +143,3 @@ void mq_waitirq(FAR struct tcb_s *wtcb, int errcode)
 
   irqrestore(saved_state);
 }
-