do not try to "analyze" or "sort index" in the table that has no indexes or no...

do not try to "analyze" or "sort index" in the table that has no indexes or no records if --check-only-changed option is used.
It's because such a table is never marked as "analyzed" or "sorted", so --check-only-changed doesn't work

myisam/myisamchk.c

@@ -794,15 +794,18 @@ static int myisamchk(MI_CHECK *param, my_string filename)
 	  !(param->testflag & T_CHECK_ONLY_CHANGED))))
       need_to_check=1;
 
-    if ((param->testflag & T_STATISTICS) &&
-	(share->state.changed & STATE_NOT_ANALYZED))
-      need_to_check=1;
-    if ((param->testflag & T_SORT_INDEX) &&
-	(share->state.changed & STATE_NOT_SORTED_PAGES))
-      need_to_check=1;
-    if ((param->testflag & T_REP_BY_SORT) &&
-	(share->state.changed & STATE_NOT_OPTIMIZED_KEYS))
-      need_to_check=1;
+    if (info->s->base.keys && info->state->records)
+    {
+      if ((param->testflag & T_STATISTICS) &&
+          (share->state.changed & STATE_NOT_ANALYZED))
+        need_to_check=1;
+      if ((param->testflag & T_SORT_INDEX) &&
+          (share->state.changed & STATE_NOT_SORTED_PAGES))
+        need_to_check=1;
+      if ((param->testflag & T_REP_BY_SORT) &&
+          (share->state.changed & STATE_NOT_OPTIMIZED_KEYS))
+        need_to_check=1;
+    }
     if ((param->testflag & T_CHECK_ONLY_CHANGED) &&
 	(share->state.changed & (STATE_CHANGED | STATE_CRASHED |
 				 STATE_CRASHED_ON_REPAIR)))