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From: ZyX <kp-pav@yandex.ru>
To: Mikael Magnusson <mikachu@gmail.com>
Cc: Peter Stephenson <p.stephenson@samsung.com>,
	zsh workers <zsh-workers@zsh.org>
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	<1999441420503885@web17g.yandex.ru> <CAHYJk3QP+mPCGpjia6aB+UxwGa9ePVceK7v4RBu-aMC5epYLRw@mail.gmail.com>
Subject: Re: Fishier code in handlefeatures
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Date: Tue, 06 Jan 2015 03:36:09 +0300
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06.01.2015, 03:32, "Mikael Magnusson" <mikachu@gmail.com>:
> On Tue, Jan 6, 2015 at 1:24 AM, ZyX <kp-pav@yandex.ru> wrote:
>> š06.01.2015, 03:21, "Mikael Magnusson" <mikachu@gmail.com>:
>>> šmod_export int
>>> šhandlefeatures(Module m, Features f, int **enables)
>>> š{
>>> šššššif (!enables || *enables)
>>> šššššššreturn setfeatureenables(m, f, *enables);
>>> ššššš*enables = getfeatureenables(m, f);
>>> šššššreturn 0;
>>> š}
>>>
>>> šso if enables is NULL, we immediately do *enables? I'm not sure what's
>>> šintended here but obviously it somehow works.
>> šNULL is false, so if enables is NULL !enables is true and *enables is not evaluated due to short-circuiting. Nothing wrong here.
>
> Read the next line too.

Ah. You mean dereference in function arguments, good catch.

Guess this code means that `enables` is never NULL and first part of the condition should be dropped in order not to confuse people.

>
> --
> Mikael Magnusson