We destroy classes of dl()'ed modules in clean_module_classes(), during
shutdown. Child classes of a module use structures of the parent class (such as
inherited properties), which are destroyed earlier, so we have a use-after-free
when destroying a child class.
Here I destroy classes in reverse order, as it is done in zend_shutdown() for
persistent classes.
Fixes GH-17961
Fixes GH-15367
When observer is enabled, we normally add an extra temporary to all
functions, to store the previously observed frame. However, this is done in
zend_observer_post_startup() so it doesn't happen to dl'ed() functions.
One possible fix would be to move that from zend_observer_post_startup()
to zend_register_functions(), but this would be too early: Observer may
not be enabled when zend_register_functions() is called, and may still be
enabled later.
However, when zend_register_functions() is called at run-time (during dl()),
we know definitively whether observer is enabled.
Here I update zend_register_functions() to add a temporary to dl'ed()
functions when observer is enabled.
Fixes: GH-17211
Closes: GH-17220
Using php_info_print_table_header() for "Foo: bar" looks odd and out of place,
because the whole line is colored. It is also questionable from a HTML
semantics point of view, because it does not described the columns that follow.
The use of this across extensions is inconsistent. It was part of the skeleton,
but ext/date or ext/json already use a regular row.
Add clean_module_functions() to clean functions which are registered by zend_register_functions().
The general logic of clean_module_functions() is consistent with clean_module_classes().
