diff --git a/mysql-test/suite/innodb/r/innodb.result b/mysql-test/suite/innodb/r/innodb.result
index 3aafd81084e..54908961b1c 100644
--- a/mysql-test/suite/innodb/r/innodb.result
+++ b/mysql-test/suite/innodb/r/innodb.result
@@ -1301,6 +1301,20 @@ ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fail
 update t3 set  t3.id=7  where t1.id =1 and t2.id = t1.id and t3.id = t2.id;
 ERROR 42S22: Unknown column 't1.id' in 'where clause'
 drop table t3,t2,t1;
+CREATE TABLE t1 (
+c1 VARCHAR(8), c2 VARCHAR(8),
+PRIMARY KEY (c1, c2)
+) ENGINE=InnoDB;
+CREATE TABLE t2 (
+c0 INT PRIMARY KEY,
+c1 VARCHAR(8) UNIQUE,
+FOREIGN KEY (c1) REFERENCES t1 (c1) ON UPDATE CASCADE
+) ENGINE=InnoDB;
+INSERT INTO t1 VALUES ('old', 'somevalu'), ('other', 'anyvalue');
+INSERT INTO t2 VALUES (10, 'old'), (20, 'other');
+UPDATE t1 SET c1 = 'other' WHERE c1 = 'old';
+ERROR 23000: Upholding foreign key constraints for table 't1', entry 'other-somevalu', key 2 would lead to a duplicate entry
+DROP TABLE t2,t1;
 create table t1(
 id int primary key,
 pid int,
@@ -1673,7 +1687,7 @@ variable_value - @innodb_rows_deleted_orig
 71
 SELECT variable_value - @innodb_rows_inserted_orig FROM information_schema.global_status WHERE LOWER(variable_name) = 'innodb_rows_inserted';
 variable_value - @innodb_rows_inserted_orig
-1066
+1070
 SELECT variable_value - @innodb_rows_updated_orig FROM information_schema.global_status WHERE LOWER(variable_name) = 'innodb_rows_updated';
 variable_value - @innodb_rows_updated_orig
 866
diff --git a/mysql-test/suite/innodb/t/innodb.test b/mysql-test/suite/innodb/t/innodb.test
index 69876297797..0b0e746bf2f 100644
--- a/mysql-test/suite/innodb/t/innodb.test
+++ b/mysql-test/suite/innodb/t/innodb.test
@@ -1046,6 +1046,24 @@ update t1,t2,t3 set t3.id=5, t2.id=6, t1.id=7  where t1.id =1 and t2.id = t1.id
 update t3 set  t3.id=7  where t1.id =1 and t2.id = t1.id and t3.id = t2.id;
 drop table t3,t2,t1;
 
+# test ON UPDATE CASCADE
+CREATE TABLE t1 (
+        c1 VARCHAR(8), c2 VARCHAR(8),
+	PRIMARY KEY (c1, c2)
+) ENGINE=InnoDB;
+
+CREATE TABLE t2 (
+        c0 INT PRIMARY KEY,
+        c1 VARCHAR(8) UNIQUE,
+        FOREIGN KEY (c1) REFERENCES t1 (c1) ON UPDATE CASCADE
+) ENGINE=InnoDB;
+
+INSERT INTO t1 VALUES ('old', 'somevalu'), ('other', 'anyvalue');
+INSERT INTO t2 VALUES (10, 'old'), (20, 'other');
+-- error ER_FOREIGN_DUPLICATE_KEY
+UPDATE t1 SET c1 = 'other' WHERE c1 = 'old';
+DROP TABLE t2,t1;
+
 #
 # test for recursion depth limit
 #
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index 48be2b1adef..f6156471380 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -5241,14 +5241,15 @@ calc_row_difference(
 			/* The field has changed */
 
 			ufield = uvect->fields + n_changed;
+			UNIV_MEM_INVALID(ufield, sizeof *ufield);
 
 			/* Let us use a dummy dfield to make the conversion
 			from the MySQL column format to the InnoDB format */
 
-			dict_col_copy_type(prebuilt->table->cols + i,
-					   dfield_get_type(&dfield));
-
 			if (n_len != UNIV_SQL_NULL) {
+				dict_col_copy_type(prebuilt->table->cols + i,
+						   dfield_get_type(&dfield));
+
 				buf = row_mysql_store_col_in_innobase_format(
 					&dfield,
 					(byte*)buf,
@@ -5256,7 +5257,7 @@ calc_row_difference(
 					new_mysql_row_col,
 					col_pack_len,
 					dict_table_is_comp(prebuilt->table));
-				dfield_copy_data(&ufield->new_val, &dfield);
+				dfield_copy(&ufield->new_val, &dfield);
 			} else {
 				dfield_set_null(&ufield->new_val);
 			}
diff --git a/storage/innobase/row/row0ins.c b/storage/innobase/row/row0ins.c
index 2925feb2904..6d34e3217af 100644
--- a/storage/innobase/row/row0ins.c
+++ b/storage/innobase/row/row0ins.c
@@ -437,11 +437,9 @@ row_ins_cascade_calc_update_vec(
 	dict_table_t*	table		= foreign->foreign_table;
 	dict_index_t*	index		= foreign->foreign_index;
 	upd_t*		update;
-	upd_field_t*	ufield;
 	dict_table_t*	parent_table;
 	dict_index_t*	parent_index;
 	upd_t*		parent_update;
-	upd_field_t*	parent_ufield;
 	ulint		n_fields_updated;
 	ulint		parent_field_no;
 	ulint		i;
@@ -477,13 +475,15 @@ row_ins_cascade_calc_update_vec(
 			dict_index_get_nth_col_no(parent_index, i));
 
 		for (j = 0; j < parent_update->n_fields; j++) {
-			parent_ufield = parent_update->fields + j;
+			const upd_field_t*	parent_ufield
+				= &parent_update->fields[j];
 
 			if (parent_ufield->field_no == parent_field_no) {
 
 				ulint			min_size;
 				const dict_col_t*	col;
 				ulint			ufield_len;
+				upd_field_t*		ufield;
 
 				col = dict_index_get_nth_col(index, i);
 
@@ -496,6 +496,8 @@ row_ins_cascade_calc_update_vec(
 				ufield->field_no
 					= dict_table_get_nth_col_pos(
 					table, dict_col_get_no(col));
+
+				ufield->orig_len = 0;
 				ufield->exp = NULL;
 
 				ufield->new_val = parent_ufield->new_val;
@@ -983,10 +985,9 @@ row_ins_foreign_check_on_constraint(
 		goto nonstandard_exit_func;
 	}
 
-	if ((node->is_delete
-	     && (foreign->type & DICT_FOREIGN_ON_DELETE_SET_NULL))
-	    || (!node->is_delete
-		&& (foreign->type & DICT_FOREIGN_ON_UPDATE_SET_NULL))) {
+	if (node->is_delete
+	    ? (foreign->type & DICT_FOREIGN_ON_DELETE_SET_NULL)
+	    : (foreign->type & DICT_FOREIGN_ON_UPDATE_SET_NULL)) {
 
 		/* Build the appropriate update vector which sets
 		foreign->n_fields first fields in rec to SQL NULL */
@@ -995,6 +996,8 @@ row_ins_foreign_check_on_constraint(
 
 		update->info_bits = 0;
 		update->n_fields = foreign->n_fields;
+		UNIV_MEM_INVALID(update->fields,
+				 update->n_fields * sizeof *update->fields);
 
 		for (i = 0; i < foreign->n_fields; i++) {
 			upd_field_t*	ufield = &update->fields[i];