This removes object auto-vivification support.
This also means that we can remove the corresponding special
handling for typed properites: We no longer need to check that a
property is convertible to stdClass if such a conversion might
take place indirectly due to a nested property write.
Additionally OBJ_W style operations now no longer modify the
object operand, and as such we no longer need to treat op1 as a
def in SSA form.
The next step would be to actually compile the whole LHS of OBJ_W
operations in R rather than W mode, but that causes issues with
SimpleXML, whose object handlers depend on the current compilation
structure.
Part of https://wiki.php.net/rfc/engine_warnings.
is pretty non-intuitive. If the same value was 1 or true you get a warning and it halts.
Since we can't break BC completely (yet) lets bump this from E_STRICT.
Also added a new section to UPGRADING for engine changes.
<?php
$x = '';
// $x = null;
// $x = false;
$x->baz = 1;
var_dump($x);
$y = 1;
$y->baz = 1;
var_dump($y);
