btr_index_rec_validate(): Account for instant ADD COLUMN

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

 CREATE TABLE t1(a INT PRIMARY KEY, b INT, KEY(b)) ENGINE=InnoDB
-PARTITION BY KEY() PARTITIONS 3;
+ROW_FORMAT=REDUNDANT PARTITION BY KEY() PARTITIONS 3;
 INSERT INTO t1 (a) VALUES (1),(2),(3),(4),(5);
 SET @saved_dbug= @@SESSION.debug_dbug;
 SET DEBUG_DBUG='+d,ib_commit_inplace_fail_2';
 ALTER TABLE t1 ADD COLUMN c CHAR(3) DEFAULT 'lie';
 ERROR HY000: Internal error: Injected error!
 SET DEBUG_DBUG= @saved_dbug;
+CHECK TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	check	status	OK
 BEGIN;
 UPDATE t1 SET b=a+1;
 INSERT INTO t1 VALUES (0,1);
@@ -22,6 +25,9 @@ SET DEBUG_DBUG='+d,ib_commit_inplace_fail_1';
 ALTER TABLE t1 ADD COLUMN d INT NOT NULL DEFAULT -42;
 ERROR HY000: Internal error: Injected error!
 SET DEBUG_DBUG= @saved_dbug;
+CHECK TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	check	status	OK
 BEGIN;
 DELETE FROM t1;
 INSERT INTO t1 VALUES (1,2,'foo');
@@ -34,7 +40,7 @@ t1	CREATE TABLE `t1` (
   `c` char(3) DEFAULT 'lie',
   PRIMARY KEY (`a`),
   KEY `b` (`b`)
-) ENGINE=InnoDB DEFAULT CHARSET=latin1
+) ENGINE=InnoDB DEFAULT CHARSET=latin1 ROW_FORMAT=REDUNDANT
  PARTITION BY KEY ()
 PARTITIONS 3
 DROP TABLE t1;

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

@@ -3,13 +3,14 @@
 --source include/have_partition.inc
 
 CREATE TABLE t1(a INT PRIMARY KEY, b INT, KEY(b)) ENGINE=InnoDB
-PARTITION BY KEY() PARTITIONS 3;
+ROW_FORMAT=REDUNDANT PARTITION BY KEY() PARTITIONS 3;
 INSERT INTO t1 (a) VALUES (1),(2),(3),(4),(5);
 SET @saved_dbug= @@SESSION.debug_dbug;
 SET DEBUG_DBUG='+d,ib_commit_inplace_fail_2';
 --error ER_INTERNAL_ERROR
 ALTER TABLE t1 ADD COLUMN c CHAR(3) DEFAULT 'lie';
 SET DEBUG_DBUG= @saved_dbug;
+CHECK TABLE t1;
 BEGIN;
 UPDATE t1 SET b=a+1;
 INSERT INTO t1 VALUES (0,1);
@@ -20,6 +21,7 @@ SET DEBUG_DBUG='+d,ib_commit_inplace_fail_1';
 --error ER_INTERNAL_ERROR
 ALTER TABLE t1 ADD COLUMN d INT NOT NULL DEFAULT -42;
 SET DEBUG_DBUG= @saved_dbug;
+CHECK TABLE t1;
 BEGIN;
 DELETE FROM t1;
 INSERT INTO t1 VALUES (1,2,'foo');

storage/innobase/btr/btr0btr.cc

@@ -4659,8 +4659,6 @@ btr_index_rec_validate(
 						and page on error */
 {
 	ulint		len;
-	ulint		n;
-	ulint		i;
 	const page_t*	page;
 	mem_heap_t*	heap	= NULL;
 	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
@@ -4691,31 +4689,34 @@ btr_index_rec_validate(
 		return(FALSE);
 	}
 
-	n = dict_index_get_n_fields(index);
-
-	if (!page_is_comp(page)
-	    && (rec_get_n_fields_old(rec) != n
-		/* a record for older SYS_INDEXES table
-		(missing merge_threshold column) is acceptable. */
-		&& !(index->id == DICT_INDEXES_ID
-		     && rec_get_n_fields_old(rec) == n - 1))) {
-		btr_index_rec_validate_report(page, rec, index);
+	if (!page_is_comp(page)) {
+		const ulint n_rec_fields = rec_get_n_fields_old(rec);
+		if (n_rec_fields == DICT_FLD__SYS_INDEXES__MERGE_THRESHOLD
+		    && index->id == DICT_INDEXES_ID) {
+			/* A record for older SYS_INDEXES table
+			(missing merge_threshold column) is acceptable. */
+		} else if (n_rec_fields < index->n_core_fields
+			   || n_rec_fields > index->n_fields) {
+			btr_index_rec_validate_report(page, rec, index);
 
-		ib::error() << "Has " << rec_get_n_fields_old(rec)
-			<< " fields, should have " << n;
+			ib::error() << "Has " << rec_get_n_fields_old(rec)
+				    << " fields, should have "
+				    << index->n_core_fields << ".."
+				    << index->n_fields;
 
-		if (dump_on_error) {
-			fputs("InnoDB: corrupt record ", stderr);
-			rec_print_old(stderr, rec);
-			putc('\n', stderr);
+			if (dump_on_error) {
+				fputs("InnoDB: corrupt record ", stderr);
+				rec_print_old(stderr, rec);
+				putc('\n', stderr);
+			}
+			return(FALSE);
 		}
-		return(FALSE);
 	}
 
 	offsets = rec_get_offsets(rec, index, offsets, page_is_leaf(page),
 				  ULINT_UNDEFINED, &heap);
 
-	for (i = 0; i < n; i++) {
+	for (unsigned i = 0; i < index->n_fields; i++) {
 		dict_field_t*	field = dict_index_get_nth_field(index, i);
 		ulint		fixed_size = dict_col_get_fixed_size(
 						dict_field_get_col(field),