Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:79399
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain gmx.de designates 212.227.17.20 as permitted sender)
Message-ID: <547F741D.6030507@gmx.de>
Date: Wed, 03 Dec 2014 21:35:41 +0100
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0
MIME-Version: 1.0
To: internals@lists.php.net
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Conversion of SplFileInfo instances to boolean
From: cmbecker69@gmx.de (Christoph Becker)

Hello internals,

today I stumbled over issue #65213[1] which has been reported as a bug,
but was changed to a feature request without any hint why the conversion
of SplFileInfo instances to boolean throws a catchable fatal error.

Even worse, due to optimizations in OPcache (and maybe other optimizers
as well), this does not always happen.  Consider the following snippet:

    <?php

    $o = new SplFileObject('.');
    if (!$o) {
    } else {
        var_dump(!$o);
    }

Without any optimization this throws the error in line 4 (the if
clause); with OPcache the error is thrown in line 6.  Apparently that is
caused by a optimization where BOOL_NOT,JMPZ is converted to NOP,JMPNZ[2].

IOW: with OPcache enabled `if (!$o)` works fine, but without OPcache it
is an error.  IMHO both should behave identically.

[1] <https://bugs.php.net/bug.php?id=65213>
[2] <http://lxr.php.net/xref/PHP_5_5/ext/opcache/Optimizer/block_pass.c#816>

-- 
Christoph M. Becker