Fix a harmless debug assertion failure

btr_page_reorganize_low(): Call lock_move_reorganize_page()
only after restoring the "infimum" and "supremum" records,
to avoid an assertion failure that these records differ.

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

@@ -509,6 +509,12 @@ SELECT * FROM t1;
 b	c	a
 NULL	NULL	NULL
 DROP TABLE t1;
+CREATE TABLE t1 (t TEXT) ENGINE=InnoDB ROW_FORMAT=REDUNDANT;
+SET @t=REPEAT('x',@@innodb_page_size / 2);
+INSERT INTO t1 VALUES (@t),(@t),(@t),(@t),(@t),(@t),(NULL),(@t),(@t),(@t),(@t);
+ALTER TABLE t1 ADD COLUMN a INT FIRST;
+UPDATE t1 SET a = 0;
+DROP TABLE t1;
 CREATE TABLE t1
 (id INT PRIMARY KEY, c2 INT UNIQUE,
 c3 POINT NOT NULL DEFAULT ST_GeomFromText('POINT(3 4)'),
@@ -964,6 +970,12 @@ SELECT * FROM t1;
 b	c	a
 NULL	NULL	NULL
 DROP TABLE t1;
+CREATE TABLE t1 (t TEXT) ENGINE=InnoDB ROW_FORMAT=COMPACT;
+SET @t=REPEAT('x',@@innodb_page_size / 2);
+INSERT INTO t1 VALUES (@t),(@t),(@t),(@t),(@t),(@t),(NULL),(@t),(@t),(@t),(@t);
+ALTER TABLE t1 ADD COLUMN a INT FIRST;
+UPDATE t1 SET a = 0;
+DROP TABLE t1;
 CREATE TABLE t1
 (id INT PRIMARY KEY, c2 INT UNIQUE,
 c3 POINT NOT NULL DEFAULT ST_GeomFromText('POINT(3 4)'),
@@ -1419,10 +1431,16 @@ SELECT * FROM t1;
 b	c	a
 NULL	NULL	NULL
 DROP TABLE t1;
+CREATE TABLE t1 (t TEXT) ENGINE=InnoDB ROW_FORMAT=DYNAMIC;
+SET @t=REPEAT('x',@@innodb_page_size / 2);
+INSERT INTO t1 VALUES (@t),(@t),(@t),(@t),(@t),(@t),(NULL),(@t),(@t),(@t),(@t);
+ALTER TABLE t1 ADD COLUMN a INT FIRST;
+UPDATE t1 SET a = 0;
+DROP TABLE t1;
 disconnect analyze;
 SELECT variable_value-@old_instant instants
 FROM information_schema.global_status
 WHERE variable_name = 'innodb_instant_alter_column';
 instants
-69
+72
 SET GLOBAL innodb_purge_rseg_truncate_frequency= @saved_frequency;

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

@@ -383,6 +383,13 @@ ALTER TABLE t1 ADD COLUMN b INT FIRST, ADD COLUMN c INT AFTER b;
 SELECT * FROM t1;
 DROP TABLE t1;
 
+eval CREATE TABLE t1 (t TEXT) $engine;
+SET @t=REPEAT('x',@@innodb_page_size / 2);
+INSERT INTO t1 VALUES (@t),(@t),(@t),(@t),(@t),(@t),(NULL),(@t),(@t),(@t),(@t);
+ALTER TABLE t1 ADD COLUMN a INT FIRST;
+UPDATE t1 SET a = 0;
+DROP TABLE t1;
+
 dec $format;
 }
 disconnect analyze;

storage/innobase/btr/btr0btr.cc

@@ -1660,11 +1660,6 @@ btr_page_reorganize_low(
 		goto func_exit;
 	}
 
-	if (!recovery && !dict_table_is_locking_disabled(index->table)) {
-		/* Update the record lock bitmaps */
-		lock_move_reorganize_page(block, temp_block);
-	}
-
 	data_size2 = page_get_data_size(page);
 	max_ins_size2 = page_get_max_insert_size_after_reorganize(page, 1);
 
@@ -1688,33 +1683,41 @@ btr_page_reorganize_low(
 		ut_ad(cursor->rec == page_get_infimum_rec(page));
 	}
 
-func_exit:
 #ifdef UNIV_ZIP_DEBUG
 	ut_a(!page_zip || page_zip_validate(page_zip, page, index));
 #endif /* UNIV_ZIP_DEBUG */
 
-	if (!recovery && page_is_root(temp_page)
-	    && fil_page_get_type(temp_page) == FIL_PAGE_TYPE_INSTANT) {
-		/* Preserve the PAGE_INSTANT information. */
-		ut_ad(!page_zip);
-		ut_ad(index->is_instant());
-		memcpy(FIL_PAGE_TYPE + page, FIL_PAGE_TYPE + temp_page, 2);
-		memcpy(PAGE_HEADER + PAGE_INSTANT + page,
-		       PAGE_HEADER + PAGE_INSTANT + temp_page, 2);
-		if (!index->table->instant) {
-		} else if (page_is_comp(page)) {
-			memcpy(PAGE_NEW_INFIMUM + page,
-			       PAGE_NEW_INFIMUM + temp_page, 8);
-			memcpy(PAGE_NEW_SUPREMUM + page,
-			       PAGE_NEW_SUPREMUM + temp_page, 8);
-		} else {
-			memcpy(PAGE_OLD_INFIMUM + page,
-			       PAGE_OLD_INFIMUM + temp_page, 8);
-			memcpy(PAGE_OLD_SUPREMUM + page,
-			       PAGE_OLD_SUPREMUM + temp_page, 8);
+	if (!recovery) {
+		if (page_is_root(temp_page)
+		    && fil_page_get_type(temp_page) == FIL_PAGE_TYPE_INSTANT) {
+			/* Preserve the PAGE_INSTANT information. */
+			ut_ad(!page_zip);
+			ut_ad(index->is_instant());
+			memcpy(FIL_PAGE_TYPE + page,
+			       FIL_PAGE_TYPE + temp_page, 2);
+			memcpy(PAGE_HEADER + PAGE_INSTANT + page,
+			       PAGE_HEADER + PAGE_INSTANT + temp_page, 2);
+			if (!index->table->instant) {
+			} else if (page_is_comp(page)) {
+				memcpy(PAGE_NEW_INFIMUM + page,
+				       PAGE_NEW_INFIMUM + temp_page, 8);
+				memcpy(PAGE_NEW_SUPREMUM + page,
+				       PAGE_NEW_SUPREMUM + temp_page, 8);
+			} else {
+				memcpy(PAGE_OLD_INFIMUM + page,
+				       PAGE_OLD_INFIMUM + temp_page, 8);
+				memcpy(PAGE_OLD_SUPREMUM + page,
+				       PAGE_OLD_SUPREMUM + temp_page, 8);
+			}
+		}
+
+		if (!dict_table_is_locking_disabled(index->table)) {
+			/* Update the record lock bitmaps */
+			lock_move_reorganize_page(block, temp_block);
 		}
 	}
 
+func_exit:
 	buf_block_free(temp_block);
 
 	/* Restore logging mode */