Assertion in ha_rnd_init on multi-table UPDATE

  create table t1 (a int, b int) engine=myisam;

  insert into t1 values (1,1),(2,2);

  create table t2 (a int) engine=myisam;

  insert into t2 values (1),(2);

  create table t3 (c int) engine=myisam;

  insert into t3 values (1),(2);

  create view v1 as select t1.a, t1.b from t2 join t1 on t1.a=t2.a

    where t1.b>0 with check option;

  update v1, t3 set v1.b=v1.b+100, t3.c=t3.c+10;