fix: CHECK and DEFAULT after CREATE ... SELECT

expression defaults and check constraints should behave as
constant default values - copied from fields, not copied from expressions

mysql-test/r/default.result

@@ -3063,3 +3063,21 @@ t1	CREATE TABLE `t1` (
   `c` int(11) DEFAULT (-a)
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
+create table t1 (a int default 5 check (a>10), b int default (5+5), c int as (a+b));
+create table t2 as select a, b, c from t1;
+create table t3 as select max(a), max(b), max(c) from t1;
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` int(11) DEFAULT 5 CHECK (a>10),
+  `b` int(11) DEFAULT (5+5),
+  `c` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+show create table t3;
+Table	Create Table
+t3	CREATE TABLE `t3` (
+  `max(a)` int(11) DEFAULT NULL,
+  `max(b)` int(11) DEFAULT NULL,
+  `max(c)` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop table t1, t2, t3;

mysql-test/t/default.test

@@ -1827,3 +1827,13 @@ alter table t1 alter a set default (2+3), alter b set default 4,
 alter table t1 alter a set default 1+2;
 show create table t1;
 drop table t1;
+
+#
+# CREATE ... SELECT
+#
+create table t1 (a int default 5 check (a>10), b int default (5+5), c int as (a+b));
+create table t2 as select a, b, c from t1;
+create table t3 as select max(a), max(b), max(c) from t1;
+show create table t2;
+show create table t3;
+drop table t1, t2, t3;

sql/field.cc

@@ -10482,8 +10482,8 @@ Column_definition::Column_definition(THD *thd, Field *old_field,
   comment=    old_field->comment;
   decimals=   old_field->decimals();
   vcol_info=  old_field->vcol_info;
-  default_value=    old_field->default_value;
-  check_constraint= old_field->check_constraint;
+  default_value= orig_field ? orig_field->default_value : 0;
+  check_constraint= orig_field ? orig_field->check_constraint : 0;
   option_list= old_field->option_list;
 
   switch (sql_type) {