Description:
------------
The way PHP handles property assignation on scalar variables evaluating 
as false is inconsistent.

Reproduce code:
---------------
<?php
$var1->test = true;

$var2 = null;
$var2->test = true;

$var3 = false;
$var3->test = true;

$var3 = '';
$var3->test = true;

$var4 = 0;
$var4->test = true;

$var5 = '0';
$var5->test = true;

$var6 = array();
$var6->test = true;
?>

Expected result:
----------------
PHP should handle every case the same way, with a "Warning: Attempt to 
assign property of non-object". The first line should also trigger a 
notice since the $var1 variable is undeclared.

Actual result:
--------------
PHP behaves as with arrays and only triggers a warning for the last 
three. The other lines create an stdClass object with the test property 
set.