diff --git a/mysql-test/main/gis.result b/mysql-test/main/gis.result
index 5190e4ff4fd1c..00506d1b0d636 100644
--- a/mysql-test/main/gis.result
+++ b/mysql-test/main/gis.result
@@ -5622,3 +5622,13 @@ t
 #
 # End of 11.6 tests
 #
+#
+# Start of 12.2 tests
+#
+#
+# MDEV-38099:  Assertion failed in st_select_lex::optimize_unflattened_subqueries
+#
+SELECT (WITH cte AS (SELECT st_astext(ST_GeomFromText('POLYGON((1 1,2 2,1 1))'))) SELECT * FROM cte);
+(WITH cte AS (SELECT st_astext(ST_GeomFromText('POLYGON((1 1,2 2,1 1))'))) SELECT * FROM cte)
+POLYGON((1 1,2 2,1 1))
+# End of 12.2 tests
diff --git a/mysql-test/main/gis.test b/mysql-test/main/gis.test
index fd604a363a68b..d3ae097a237b8 100644
--- a/mysql-test/main/gis.test
+++ b/mysql-test/main/gis.test
@@ -3623,3 +3623,14 @@ SELECT ST_ISVALID(ST_GEOMFROMTEXT('POLYGON((0 0, 10 0, 10 10, 0 10, 0 0), (15 15
 --echo #
 --echo # End of 11.6 tests
 --echo #
+
+--echo #
+--echo # Start of 12.2 tests
+--echo #
+
+--echo #
+--echo # MDEV-38099:  Assertion failed in st_select_lex::optimize_unflattened_subqueries
+--echo #
+SELECT (WITH cte AS (SELECT st_astext(ST_GeomFromText('POLYGON((1 1,2 2,1 1))'))) SELECT * FROM cte);
+
+--echo # End of 12.2 tests
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 73d97861325ef..7779411ff8a98 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -11130,6 +11130,8 @@ void st_select_lex::register_unit(SELECT_LEX_UNIT *unit,
   slave= unit;
   unit->master= this;
   uncacheable|= unit->uncacheable;
+  if (master && (unit->uncacheable & UNCACHEABLE_RAND))
+    master->uncacheable|= UNCACHEABLE_RAND;
 
   for(SELECT_LEX *sel= unit->first_select();sel; sel= sel->next_select())
   {