Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:103529
MIME-Version: 1.0
In-Reply-To: <CAF+90c_wZvdgVbmdHH+7J=CLx-rivDRr4vB3=HXK3K2HSNAqMg@mail.gmail.com>
References: <CAF+90c_wZvdgVbmdHH+7J=CLx-rivDRr4vB3=HXK3K2HSNAqMg@mail.gmail.com>
Date: Wed, 28 Nov 2018 20:44:32 -0800
Message-ID: <CAJVEVOaZWJPNS9YMU=xp2oKqXe=R3ASeA9jxz0kmS-QeLR-OJA@mail.gmail.com>
To: Nikita Popov <nikita.ppv@gmail.com>
Cc: PHP internals <internals@lists.php.net>
Content-Type: text/plain; charset="UTF-8"
Subject: Re: [PHP-DEV] Don't silence fatal errors
From: fwentish@gmail.com (Fwentish Aelondes)

Breaking BC might be unnecessary if instead of changing the default
behavior of @, you add an additional flag to error_reporting that
enables the new behavior, something like E_UNSILENCE_FATAL. Then
developers would only need to switch a flag in php.ini to get the old
behavior back, instead of re-working existing code around the new
behavior.

On 11/26/18, Nikita Popov <nikita.ppv@gmail.com> wrote:
>  Hi internals,
>
> When the silencing operator @ is used, the intention is generally to
> silence expected warnings or notices. However, it currently also silences
> fatal errors. As fatal errors also abort request execution, the result will
> often be a hard to debug white screen of death.
>
> The most recent occurrence which motivated me to write this mail is
> https://bugs.php.net/bug.php?id=77205, but I've seen this play out multiple
> times already.
>
> I would like to propose to change the behavior of @ to only silence
> warnings, notices and other low-level diagnostics, but leave fatal errors
> intake. In particular, the following should not be silenced:
>
> * E_ERROR
> * E_CORE_ERROR
> * E_COMPILE_ERROR
> * E_USER_ERROR
> * E_RECOVERABLE_ERROR
> * E_PARSE
>
> This change would have two main implications for backwards compatibility:
>
> 1. Code that legitimately wants to silence fatal errors for whatever reason
> should now use error_reporting() (or ini_set()) to do so, instead of @.
>
> 2. Error handlers that want to only handle non-silenced errors may have to
> be adjusted. A common pattern I found in our own tests if checks for
> error_reporting() != 0 to detect silencing. This should be changed to
> error_reporting() & $err_no to detect whether the specific error type is
> silenced.
>
> A preliminary patch for this change is available at
> https://github.com/php/php-src/pull/3685.
>
> What do you think about this?
>
> Nikita
>