zval_dtor() doesn't make a lot of sense in PHP-7.* and it's used incorrectly in some places.
Its occurances should be replaced by zval_ptr_dtor() or zval_ptr_dtor_nogc(), or even more specialized destructors.
These are either in debug code (fix them), commented out (drop
them) or in dead compatibility macros (drop them).
One usage was in php_stream_get_from_zval(), which we have not used
since at least PHP 5.2 and, judging from the fact that nobody
complained about it causing compile errors in PHP 7, nobody else
uses it either, so drop it.
There are still remaining uses in mysqli embedded and odbc birdstep.
These probably need to be dropped outright.
Now each HashTable is also zend_array, so it's refcounted and may be a subject for Copy on Write
zend_array_dup() was changed to allocate and return HashTable, instead of taking preallocated HashTable as argument.
* PHP-5.6:
fix output globals importing
export output globals
use portable strndup implementation
unix sockets aren't available on windows
dll export APIs needed by phpdbg
fix sapi/phpdbg/config.w32
Don't treat warnings as failures in the junit output
