Fixed the bug mdev-13734.

If the method SELECT_LEX::mark_const_derived() is called for a select
that is used in the specification of a materialized derived table / view D
then method should not set the flag fill_me for D on when
the flag JOIN::with_two_phase_optimization is set on for this select.

mysql-test/r/derived_cond_pushdown.result

@@ -10165,3 +10165,17 @@ WHERE d IN ( SELECT * FROM v1 ) AND c LIKE 'z%' OR c IS NULL;
 c	d
 DROP VIEW v1;
 DROP TABLE t1,t2,t3;
+#
+# MDEV-13734: Optimization for equi-joins of grouping derived tables
+#             (Splitting derived tables / views with GROUP BY) :
+#             derived table / view is empty
+#
+CREATE TABLE t1 (a int, b int, INDEX(a)) ENGINE=MyISAM;
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+CREATE VIEW v1 AS SELECT a, b FROM t1 STRAIGHT_JOIN t2;
+CREATE VIEW v2 AS SELECT a, max(b) as bmax FROM v1 GROUP BY a;
+CREATE VIEW v3 AS SELECT v2.* FROM t1 JOIN v2 ON t1.b = v2.bmax ;
+SELECT * FROM v3 JOIN t1 ON (bmax = b);
+a	bmax	a	b
+DROP VIEW v1,v2,v3;
+DROP TABLE t1,t2;

mysql-test/t/derived_cond_pushdown.test

@@ -1816,3 +1816,21 @@ SELECT * FROM t3
 
 DROP VIEW v1;
 DROP TABLE t1,t2,t3;
+
+--echo #
+--echo # MDEV-13734: Optimization for equi-joins of grouping derived tables
+--echo #             (Splitting derived tables / views with GROUP BY) :
+--echo #             derived table / view is empty
+--echo #
+
+CREATE TABLE t1 (a int, b int, INDEX(a)) ENGINE=MyISAM;
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+
+CREATE VIEW v1 AS SELECT a, b FROM t1 STRAIGHT_JOIN t2;
+CREATE VIEW v2 AS SELECT a, max(b) as bmax FROM v1 GROUP BY a;
+CREATE VIEW v3 AS SELECT v2.* FROM t1 JOIN v2 ON t1.b = v2.bmax ;
+
+SELECT * FROM v3 JOIN t1 ON (bmax = b);
+
+DROP VIEW v1,v2,v3;
+DROP TABLE t1,t2;

sql/sql_lex.cc

@@ -4608,7 +4608,8 @@ void SELECT_LEX::mark_const_derived(bool empty)
   {
     if (!empty)
       increase_derived_records(1);
-    if (!master_unit()->is_unit_op() && !derived->is_merged_derived())
+    if (!master_unit()->is_unit_op() && !derived->is_merged_derived() &&
+        !(join && join->with_two_phase_optimization))
       derived->fill_me= TRUE;
   }
 }