This looks wrong. It will free the return_value altogether, and not just the data associated with it. Shouldn't it be zval_ptr_dtor() instead?

@derickr Thanks for the review! Does it look good to merge now? :)

I've tried your patch on master with the following code:

for ( $i = 0; $i < 10000; $i++ ) {
    $d = DateTime::createFromFormat('m-d-Y', 'asdf asdf');
    unset($d);

    if ($i % 100 == 0) {
        echo 'Memory usage: ', memory_get_usage(), PHP_EOL;
    }
}

The memory usage keeps going down, becomes negative and then crashes.

@datibbaw thanks for feedback! I've run this test code against patched master and didn't see any memory usage going down. Could you post you ./configure parameters?

@Entea I've managed to reproduce it on two systems now. This is my config.nice:

'./configure' \
'--disable-all' \
'--enable-maintainer-zts' \
'--with-openssl=/usr/local/opt/openssl' \
'--with-libedit' \
'YACC=/usr/local/opt/bison27/bin/bison' \
'--enable-json' \
"$@"

This PR has been superseded by #768, which has been merged.