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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Sun, 27 Feb 2022 19:09:03 +0100
Message-ID: <CANiq72m28WrjVHkcg5Y0LDa51Ur4OCpFbGdcq+v4gqiC0Wi6zg@mail.gmail.com>
Subject: Re: [RFC PATCH 03/13] usb: remove the usage of the list iterator
 after the loop
To:     Segher Boessenkool <segher@kernel.crashing.org>
Cc:     David Laight <David.Laight@aculab.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Jakob <jakobkoschel@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-arch <linux-arch@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        Mike Rapoport <rppt@kernel.org>,
        "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        Brian Johannesmeyer <bjohannesmeyer@gmail.com>,
        Cristiano Giuffrida <c.giuffrida@vu.nl>,
        "Bos, H.J." <h.j.bos@vu.nl>
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On Sun, Feb 27, 2022 at 1:09 PM Segher Boessenkool
<segher@kernel.crashing.org> wrote:
>
> How will you define dividing by zero so that its behaviour is reasonable
> for every program, for example?

The solution is to let the developer specify what they need to happen.
That choice should include the unsafe possibility (i.e. unchecked),
because sometimes that is precisely what we need.

> Invoking an error handler at runtime
> has most of the same unwanted effects, except is is never silent.  You

It may not be what it is needed in some cases (thus the necessity to
be able to choose), but at least one can predict what happens and
different compilers, versions, flags, inputs, etc. would agree.

Cheers,
Miguel