Description:
------------
The following code from php_mysql.c trashes the default_password,
obtained from the php.ini file.

passwd = MySG(default_password);
...
case 3: {

convert_to_string_ex(z_user);
convert_to_string_ex(z_passwd);
user = Z_STRVAL_PP(z_user);
passwd = Z_STRVAL_PP(z_passwd);
}


Reproduce code:
---------------
Set the mysql default password in the php.ini file and call mysql connect as follows:

mysql(foo, bar, null, TRUE);



Expected result:
----------------
passwd should not be set if argument is null.



Actual result:
--------------
Empty password is send to mysql.