diff --git a/mysql-test/main/func_equal.result b/mysql-test/main/func_equal.result
index 4f876b4f27bfe..90048f13e6934 100644
--- a/mysql-test/main/func_equal.result
+++ b/mysql-test/main/func_equal.result
@@ -54,3 +54,17 @@ c1
 0
 DROP TABLE t0;
 # End of 10.5 tests
+#
+# MDEV-36964: Stack looping, SIGSEGVs in `Item_hybrid_func::type_handler` and `Item::check_cols` on SELECT when using a function
+#
+CREATE FUNCTION f() RETURNS ROW TYPE OF t RETURN 1;
+CREATE TABLE t (c INT KEY,c2 INT,UNIQUE (c2));
+SELECT ROW(COALESCE(f()),1)=ROW(1,1) AS eq;
+ERROR HY000: Illegal parameter data type row for operation 'coalesce'
+SELECT ROW(COALESCE(f()),1)=ROW(COALESCE(f()),1) AS eq;
+ERROR HY000: Illegal parameter data type row for operation 'coalesce'
+SELECT ROW(1, COALESCE(f()), 1)=ROW(1, COALESCE(f()), 1) AS eq;
+ERROR HY000: Illegal parameter data type row for operation 'coalesce'
+DROP FUNCTION f;
+DROP TABLE t;
+#
diff --git a/mysql-test/main/func_equal.test b/mysql-test/main/func_equal.test
index 88cab9e95a0f2..47b13a7058fa4 100644
--- a/mysql-test/main/func_equal.test
+++ b/mysql-test/main/func_equal.test
@@ -59,3 +59,24 @@ DROP TABLE t0;
 
 
 --echo # End of 10.5 tests
+
+--echo #
+--echo # MDEV-36964: Stack looping, SIGSEGVs in `Item_hybrid_func::type_handler` and `Item::check_cols` on SELECT when using a function
+--echo #
+
+CREATE FUNCTION f() RETURNS ROW TYPE OF t RETURN 1;
+CREATE TABLE t (c INT KEY,c2 INT,UNIQUE (c2));
+
+--error ER_ILLEGAL_PARAMETER_DATA_TYPE_FOR_OPERATION
+SELECT ROW(COALESCE(f()),1)=ROW(1,1) AS eq;
+
+--error ER_ILLEGAL_PARAMETER_DATA_TYPE_FOR_OPERATION
+SELECT ROW(COALESCE(f()),1)=ROW(COALESCE(f()),1) AS eq;
+
+--error ER_ILLEGAL_PARAMETER_DATA_TYPE_FOR_OPERATION
+SELECT ROW(1, COALESCE(f()), 1)=ROW(1, COALESCE(f()), 1) AS eq;
+
+DROP FUNCTION f;
+DROP TABLE t;
+
+--echo #
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index eaa705642d843..aec3d1d9ff51b 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -60,9 +60,16 @@ static int cmp_row_type(Item* item1, Item* item2)
     return 1;
   for (uint i=0; i<n; i++)
   {
-    if (item2->element_index(i)->check_cols(item1->element_index(i)->cols()) ||
-        (item1->element_index(i)->result_type() == ROW_RESULT &&
-         cmp_row_type(item1->element_index(i), item2->element_index(i))))
+    Item *left_item= item1->element_index(i);
+    Item *right_item= item2->element_index(i);
+
+    if (right_item->check_cols(left_item->cols()))
+      return 1;
+
+    if (!(left_item->cmp_type() == ROW_RESULT &&
+          right_item->cmp_type() == ROW_RESULT) ||
+        (item1 == left_item || item2 == right_item) ||
+         cmp_row_type(left_item, right_item))
       return 1;
   }
   return 0;
@@ -8129,4 +8136,3 @@ Item *Item_equal::multiple_equality_transformer(THD *thd, uchar *arg)
     break;
   }
 }
-