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Message-ID: <7.0.1.0.2.20060413154916.014b1d88@zend.com>
Date: Thu, 13 Apr 2006 15:52:22 -0700
To: Andrei Zmievski <andrei@gravitonic.com>,
	PHP Internals <internals@lists.php.net>
Cc: Dmitry Stogov <dmitry@zend.com>
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Subject: Re: Unicode conversion exceptions and memory leaks
From: andi@zend.com (Andi Gutmans)

As you know, exceptions were designed to be user-land and not for 
internal functionality. I warned about that more exceptions were 
being integrated into the extensions; and I especially warned of 
ideas of integrating them into language constructs such as type hints 
and conversions.
I don't have a good solution for this right now, except for adding a 
lot of bulk to C extensions and the core and making them overly 
complicated. Anyway, I'll discuss with Dmitry and see if he has any 
ideas I didn't think of.

re: this specific case. Is it really a good idea for a type 
conversion to throw an exception? People won't be expecting that from 
reading the code. They'd most likely only expect methods to throw exceptions...

Andi

At 03:44 PM 4/13/2006, Andrei Zmievski wrote:
>If you run this code in PHP 6 right now, you will get a nice memory 
>leak notice.
>
><?php
>
>unicode_set_error_mode(FROM_UNICODE, U_CONV_ERROR_STOP | 
>U_CONV_ERROR_EXCEPTION);
>
>$u = "< \u3844 >";
>try {
>     $s = (binary)$u;
>} catch (UnicodeConversionException $e) {
>}
>
>?>
>
>/homes/andrei/dev/php-src/Zend/zend_unicode.c(461) :  Freeing 
>0x013FC4E4 (1 bytes), script=e.php
>
> From what Dmitry tells me, it is impossible to fix this with the 
> way our exceptions are implemented currently. I trust him on this, 
> but at the same time I think we need to do something. The 
> conversions will be happening in a lot of place and being able to 
> catch an exception, if one results, is an important part of the 
> workflow. I think Dmitry proposed that we could re-write exceptions 
> implementation, but also said that it would be a lot of work. I 
> think we should seriously consider it, though.
>
>Thoughts?
>
>-Andrei