MDEV-30426 Assertion !rec_offs_nth_extern(offsets2, n) during bulk insert

- cmp_rec_rec_simple() fails to detect duplicate key error for
bulk insert operation

mysql-test/suite/innodb/r/insert_into_empty.result

@@ -405,3 +405,21 @@ nb_corrupted_rows
 0
 DROP TABLE t1;
 # End of 10.7 tests
+#
+#  MDEV-30426  Assertion !rec_offs_nth_extern(offsets2, n)
+#	during bulk insert
+#
+CREATE TABLE t1(f1 TEXT NOT NULL, f2 TEXT NOT NULL,
+f3 TEXT NOT NULL, f4 TEXT NOT NULL,
+f5 TEXT NOT NULL, f6 TEXT NOT NULL,
+PRIMARY KEY(f6(10)))ENGINE=InnoDB;
+BEGIN;
+INSERT INTO t1 VALUES
+(repeat('a', 200), repeat('b', 200), repeat('c', 200),
+repeat('d', 200), repeat('e', 200), repeat('f', 200)),
+(repeat('b', 20000), repeat('c', 16000), repeat('d', 12000),
+repeat('e', 12000), repeat('f', 12000), repeat('f', 12000));
+ERROR HY000: Got error 1 "Operation not permitted" during COMMIT
+COMMIT;
+DROP TABLE t1;
+# End of 10.8 tests

mysql-test/suite/innodb/t/insert_into_empty.opt

+--innodb_sort_buffer_size=65536

mysql-test/suite/innodb/t/insert_into_empty.test

@@ -424,3 +424,22 @@ SELECT COUNT(*) AS nb_corrupted_rows FROM t1 WHERE data != REPEAT('X', @@innodb_
 DROP TABLE t1;
 
 --echo # End of 10.7 tests
+
+--echo #
+--echo #  MDEV-30426  Assertion !rec_offs_nth_extern(offsets2, n)
+--echo #	during bulk insert
+--echo #
+CREATE TABLE t1(f1 TEXT NOT NULL, f2 TEXT NOT NULL,
+		f3 TEXT NOT NULL, f4 TEXT NOT NULL,
+		f5 TEXT NOT NULL, f6 TEXT NOT NULL,
+		PRIMARY KEY(f6(10)))ENGINE=InnoDB;
+BEGIN;
+--error ER_ERROR_DURING_COMMIT
+INSERT INTO t1 VALUES
+        (repeat('a', 200), repeat('b', 200), repeat('c', 200),
+         repeat('d', 200), repeat('e', 200), repeat('f', 200)),
+        (repeat('b', 20000), repeat('c', 16000), repeat('d', 12000),
+         repeat('e', 12000), repeat('f', 12000), repeat('f', 12000));
+COMMIT;
+DROP TABLE t1;
+--echo # End of 10.8 tests

storage/innobase/rem/rem0cmp.cc

@@ -725,9 +725,12 @@ cmp_rec_rec_simple(
 	/* If we ran out of fields, the ordering columns of rec1 were
 	equal to rec2. Issue a duplicate key error if needed. */
 
-	if (!null_eq && table && dict_index_is_unique(index)) {
-		/* Report erroneous row using new version of table. */
-		innobase_rec_to_mysql(table, rec1, index, offsets1);
+	if (!null_eq && index->is_unique()) {
+		if (table) {
+			/* Report erroneous row using new version
+			of table. */
+			innobase_rec_to_mysql(table, rec1, index, offsets1);
+		}
 		return(0);
 	}