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|---|---|
| From | Tim Rentsch <tr.17687@z991.linuxsc.com> |
| Newsgroups | comp.lang.c |
| Subject | Re: Working code |
| Date | Wed, 01 Sep 2021 16:58:45 -0700 |
| Organization | A noiseless patient Spider |
| Lines | 27 |
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antispam@math.uni.wroc.pl writes:
> The following is simplified version of "working code": it
> is more than 20 years old (probably closer to 30 years old)
> and apparently did what its author intended:
>
> int (*handlers[2])();
>
> #define DO_IT(n) ((p = handlers[n]) ? (*p)() : 0)
>
> static void foo() {
> register int (*p)();
> register int bar = DO_IT(0) | DO_IT(1);
> /* ... */
> /* Use of bar */
> }
>
> /* Code that fills 'handlers' and calls foo() */
>
> I wonder what you think about this code?
I think it has undefined behavior, and needlessly so:
#define DO_IT(n) (handlers[n] ? handlers[n]() : 0)
...
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Working code antispam@math.uni.wroc.pl - 2021-09-01 22:23 +0000
Re: Working code Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-09-01 16:58 -0700
Re: Working code Andrey Tarasevich <andreytarasevich@hotmail.com> - 2021-09-01 20:57 -0700
Re: Working code Ike Naar <ike@rie.sdf.org> - 2021-09-02 05:22 +0000
Re: Working code Andrey Tarasevich <andreytarasevich@hotmail.com> - 2021-09-01 22:33 -0700
Re: Working code Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-09-02 11:54 +0100
Re: Working code Richard Damon <Richard@Damon-Family.org> - 2021-09-02 07:08 -0400
Re: Working code Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-09-02 13:37 +0100
Re: Working code James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-09-02 12:03 -0400
Re: Working code Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-09-02 09:57 -0700
Re: Working code Andrey Tarasevich <andreytarasevich@hotmail.com> - 2021-09-01 21:02 -0700
Re: Working code John McCue <jmccue@obsd2.mhome.org> - 2021-09-02 13:31 +0000
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