Incorrect locking for global_query_id

[Stewart Smith]

So, the Register link for creating a bugs.mysql.com account still
doesn't work, so i'm filing a bug here:


Found in MySQl 5.6.17,

In sql/sp_head.cc:

bool sp_head::execute_function(THD *thd, Item **argp, uint argcount,

We have this code:

    mysql_mutex_lock(&LOCK_thread_count);
    q= global_query_id;
    mysql_mutex_unlock(&LOCK_thread_count);


Which is incorrect.

It should at least by a my_atomic_load64 with the appropriate lock
things around it.

I haven't looked at if the mysql_bin.log.start_union_events(thd, q+1) is
correct or not.