handler should be used with constant expressions only (or rand)

mysql-test/r/handler.result

@@ -151,4 +151,6 @@ insert into t1 values (1), (2), (3);
 handler t1 open;
 handler t1 read a=(W);
 Unknown column 'W' in 'field list'
+handler t1 read a=(a);
+Wrong arguments to HANDLER ... READ
 drop table t1;

mysql-test/t/handler.test

@@ -88,5 +88,7 @@ insert into t1 values (1), (2), (3);
 handler t1 open;
 --error 1054
 handler t1 read a=(W);
+--error 1210
+handler t1 read a=(a);
 drop table t1;
 

sql/sql_handler.cc

@@ -194,7 +194,12 @@ int mysql_ha_read(THD *thd, TABLE_LIST *tables,
       for (key_len=0 ; (item=it_ke++) ; key_part++)
       {
 	if (item->fix_fields(thd, tables))
-	    return -1;
+	  goto err;
+	if (item->used_tables() & ~RAND_TABLE_BIT)
+        {
+          my_error(ER_WRONG_ARGUMENTS,MYF(0),"HANDLER ... READ");
+	  goto err;
+        }
 	item->save_in_field(key_part->field, 1);
 	key_len+=key_part->store_length;
       }