MDEV-25971 Instant ADD COLUMN fails to issue truncation warnings

A table rebuild that would truncate the default value of a
DATE column is expected to issue data truncation warnings.
But, these warnings are not being issued if the ADD COLUMN
is being executed with ALGORITHM=INSTANT. InnoDB sets the
warning of the field while assigning the default value
of the field during check_if_supported_inplace_alter().

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

@@ -1049,13 +1049,12 @@ a
 10
 DROP TABLE t1;
 CREATE TABLE t1 (a INT NOT NULL DEFAULT 0) ENGINE=InnoDB;
-SET @save_allowed = @@GLOBAL.innodb_instant_alter_column_allowed;
-SET GLOBAL innodb_instant_alter_column_allowed=never;
-iNSERT INTO t1 VALUES (10);
-ALTER TABLE t1 ADD b DATE NOT NULL DEFAULT if(unix_timestamp()>1,TIMESTAMP'2001-01-01 10:20:30',0);
-affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
-SET GLOBAL innodb_instant_alter_column_allowed=@save_allowed;
+INSERT INTO t1 VALUES (10);
+ALTER TABLE t1 ADD b DATE NOT NULL DEFAULT if(unix_timestamp()>1,TIMESTAMP'2001-01-01 10:20:30',0), algorithm=copy;
+affected rows: 1
+info: Records: 1  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'b' at row 1
 SELECT * FROM t1;
 a	b
 10	2001-01-01
@@ -1064,7 +1063,9 @@ CREATE TABLE t1 (a INT NOT NULL DEFAULT 0) ENGINE=InnoDB;
 iNSERT INTO t1 VALUES (10);
 ALTER TABLE t1 ADD b TIME NOT NULL DEFAULT if(unix_timestamp()>1,TIMESTAMP'2001-01-01 10:20:30',0);
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'b' at row 1
 SELECT * FROM t1;
 a	b
 10	10:20:30

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

@@ -308,10 +308,14 @@ id	c2	c3	c4	c5	c6
 affected rows: 3
 ALTER TABLE t3 ADD COLUMN c7 TIME NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c7' at row 1
 ALTER TABLE t3 ADD COLUMN c8 DATE NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c8' at row 1
 SELECT id, c2, ST_AsText(c3) c3, c4, c5, c6, c7, c8 FROM t3;
 id	c2	c3	c4	c5	c6	c7	c8
 1	1	POLYGON((1 1,2 2,3 3,1 1))	1970-01-01 03:00:42	1970-01-01 03:00:42	NULL	03:00:42	1970-01-01
@@ -788,10 +792,14 @@ id	c2	c3	c4	c5	c6
 affected rows: 3
 ALTER TABLE t3 ADD COLUMN c7 TIME NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c7' at row 1
 ALTER TABLE t3 ADD COLUMN c8 DATE NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c8' at row 1
 SELECT id, c2, ST_AsText(c3) c3, c4, c5, c6, c7, c8 FROM t3;
 id	c2	c3	c4	c5	c6	c7	c8
 1	1	POLYGON((1 1,2 2,3 3,1 1))	1970-01-01 03:00:42	1970-01-01 03:00:42	NULL	03:00:42	1970-01-01
@@ -1268,10 +1276,14 @@ id	c2	c3	c4	c5	c6
 affected rows: 3
 ALTER TABLE t3 ADD COLUMN c7 TIME NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c7' at row 1
 ALTER TABLE t3 ADD COLUMN c8 DATE NOT NULL DEFAULT current_timestamp();
 affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+info: Records: 0  Duplicates: 0  Warnings: 1
+Warnings:
+Note	1265	Data truncated for column 'c8' at row 1
 SELECT id, c2, ST_AsText(c3) c3, c4, c5, c6, c7, c8 FROM t3;
 id	c2	c3	c4	c5	c6	c7	c8
 1	1	POLYGON((1 1,2 2,3 3,1 1))	1970-01-01 03:00:42	1970-01-01 03:00:42	NULL	03:00:42	1970-01-01

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

@@ -652,13 +652,10 @@ DROP TABLE t1;
 
 # DATETIME-to-DATE truncation is OK
 CREATE TABLE t1 (a INT NOT NULL DEFAULT 0) ENGINE=InnoDB;
-SET @save_allowed = @@GLOBAL.innodb_instant_alter_column_allowed;
-SET GLOBAL innodb_instant_alter_column_allowed=never;
-iNSERT INTO t1 VALUES (10);
+INSERT INTO t1 VALUES (10);
 --enable_info
-ALTER TABLE t1 ADD b DATE NOT NULL DEFAULT if(unix_timestamp()>1,TIMESTAMP'2001-01-01 10:20:30',0);
+ALTER TABLE t1 ADD b DATE NOT NULL DEFAULT if(unix_timestamp()>1,TIMESTAMP'2001-01-01 10:20:30',0), algorithm=copy;
 --disable_info
-SET GLOBAL innodb_instant_alter_column_allowed=@save_allowed;
 SELECT * FROM t1;
 DROP TABLE t1;
 

sql/sql_table.cc

@@ -10015,9 +10015,12 @@ do_continue:;
     if (alter_info->requested_lock == Alter_info::ALTER_TABLE_LOCK_NONE)
       ha_alter_info.online= true;
     // Ask storage engine whether to use copy or in-place
-    ha_alter_info.inplace_supported=
-      table->file->check_if_supported_inplace_alter(altered_table,
-                                                    &ha_alter_info);
+    {
+      Check_level_instant_set check_level_save(thd, CHECK_FIELD_WARN);
+      ha_alter_info.inplace_supported=
+        table->file->check_if_supported_inplace_alter(altered_table,
+                                                      &ha_alter_info);
+    }
 
     if (alter_info->supports_algorithm(thd, &ha_alter_info) ||
         alter_info->supports_lock(thd, &ha_alter_info))