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    Subjectgotos in kernel [Was: Re: any chance of 2.6.0-test*?]
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    Rob Wilkens <robw@optonline.net> said:
    > I'm REALLY opposed to the use of the word "goto" in any code where it's
    > not needed. OF course, I'm a linux kernel newbie, so I'm in no position
    > to comment

    My, my, my, an anti-goto zealot now.

    > Let me comment below the relevant code snippet below as to how I would
    > change it:
    >
    > On Sun, 2003-01-12 at 14:15, Linus Torvalds wrote:
    > > if (spin_trylock(&tty_lock.lock))
    > > goto got_lock;
    > > if (tsk == tty_lock.lock_owner) {
    > > WARN_ON(!tty_lock.lock_count);
    > > tty_lock.lock_count++;
    > > return flags;
    > > }
    > > spin_lock(&tty_lock.lock);
    > > got_lock:
    > > WARN_ON(tty_lock.lock_owner);
    > <etc...>
    >
    > I would change it to something like the following (without testing the
    > code through a compiler or anything to see if it's valid):

    It just to happens that sometimes the compiler generates stupid code for
    goto-less solutions. While the famous "no goto needed" theorem is certainly
    true, it duplicates lots of code to get rid of gotos, and that is a no -
    never - only over my dead body proposition in a kernel that tries to be as
    fast as humanly possible.

    And if used with care and good taste, a goto can lead to clearer, more
    understandable (and thus more probably correct) code. Just look up what
    sort of "programming style" Dijkstra was complaining about when asking to
    ban gotos, and what D. E. Knuth has to say on structured programming with
    gotos.
    --
    Dr. Horst H. von Brand User #22616 counter.li.org
    Departamento de Informatica Fono: +56 32 654431
    Universidad Tecnica Federico Santa Maria +56 32 654239
    Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513
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