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Date: Sat, 12 Aug 2017 15:37:08 +0100
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Subject: Re: [PHP-DEV] Stop Exceptions capturing object references for trace
 arguments
From: rowan.collins@gmail.com (Rowan Collins)

On 12/08/2017 04:25, Stanislav Malyshev wrote:
> Hi!
>
>> The "args" part of this contains full object references to anything that
>> happens to have been a function argument in the stack, and causes two
>> problems:
> I think it makes sense to make exception not to collect args. In fact, I
> think this may also be one of rare cases where new ini setting would be
> appropriate, where the default could be the old way (at least for now,
> for BC), and recommended production setting would be off.
>

My only concern is if anyone is using this data for anything other than 
debugging - e.g. if they were somehow extracting extra context about the 
exception by traversing the backtrace to a particular point and grabbing 
the arguments. That feels like a horrible hack to me, but that doesn't 
mean someone isn't relying on it.

An interesting side effect of an ini setting, though, is that it could 
in turn be made to raise deprecation warnings at some point, whereas 
just accessing the 'args' element of an array is pretty hard to detect. 
So for instance, we could theoretically have: 7.3, add ini setting 
defaulting to on; 7.4, change default to off and raise deprecation 
notice if it's turned on; 8.0, remove feature, error if ini setting is 
not set to on (ignore if set to off for smoother upgrades).

Regards,

-- 
Rowan Collins
[IMSoP]