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Re: Inconsistent...

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.c
Subject Re: Inconsistent...
Date 2023-11-01 13:52 +0000
Organization A noiseless patient Spider
Message-ID <87bkcdpomu.fsf@bsb.me.uk> (permalink)
References (3 earlier) <87lebjqb6g.fsf@bsb.me.uk> <uhroij$16v9f$1@dont-email.me> <874ji6qp40.fsf@bsb.me.uk> <uhtb2h$3gfat$2@i2pn2.org> <uhtem5$1jnt4$1@dont-email.me>

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David Brown <david.brown@hesbynett.no> writes:

> On 01/11/2023 11:59, bart wrote:
>> On 01/11/2023 00:44, Ben Bacarisse wrote:
>>> "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:
>>>
>>>> On 10/31/2023 4:32 AM, Ben Bacarisse wrote:
>>>
>>>>> But the result is also undefined when mp_char does not occur in the
>>>>> string which can happen for two printable ASCII characters.
>>>>> Chris, you should test your code more thoroughly.
>>>>
>>>> Yup. This was quickly fleshed out a while back, and I recently got
>>>> reminded
>>>> if it. So, I ran it again, and noticed the inconsistent behavior between
>>>> the
>>>> two compilers, (MSVC and GCC). This has to be due to undefined behavior
>>>> in
>>>> my code. So, yes, I agree with you, Ben. Big time.
>>>
>>> I don't if you know what I'm talking about.  Did you deliberately leave
>>> out two printable ASCII characters from the alphabet?
>>>
>> Might be helpful to mention that they are | and ".
>
> | and -, as far as I could see in a quick look at the code.

No, - is there but " is not.  It's a slightly more subtle bug than just
"you have missing characters" which is why I wanted Chris to look for
himself.

> It seems bizarre to spell out lists of ASCII characters in the code rather
> than just a simple loop at runtime.

Sometimes the order matters, particularly in cryptological applications.
In this case I don't think is does though.

And if the order does not matter, then even a loop is unnecessary since
the string is used only to generate indexes into it.  A simple x - ' '
gives the index of x in the list of "printable" ASCII characters.

-- 
Ben.

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Thread

Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:01 -0700
  Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:11 -0700
  Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:30 -0700
    Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-10-30 22:01 +0000
      Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 15:09 -0700
  Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-30 23:22 +0000
    Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-30 23:44 +0000
    Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 02:05 +0000
      Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-31 11:32 +0000
        Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 14:16 +0000
          Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-31 16:15 +0000
            Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 18:35 +0000
              Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 14:05 -0700
                Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 22:29 +0000
              Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 00:39 +0000
                Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 10:35 +0000
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:29 +0000
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:52 -0700
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 14:30 -0700
        Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 13:37 -0700
          Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 00:44 +0000
            Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 20:26 -0700
              Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 11:05 +0000
            Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 10:59 +0000
              Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-01 13:01 +0100
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:52 +0000
                Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-01 20:12 +0100
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:52 -0700
                Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 10:04 +0100
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 10:51 -0700
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 11:02 -0700
                Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 20:02 +0100
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 12:03 -0700
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 23:57 -0700
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-04 00:11 -0700
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 20:28 +0000
                Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-03 10:23 +0100
                [OT] Encryption (Was: Inconsistent...) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-03 10:10 +0000
                Re: [OT] Encryption (Was: Inconsistent...) David Brown <david.brown@hesbynett.no> - 2023-11-03 15:01 +0100
                Re: [OT] Encryption (Was: Inconsistent...) scott@slp53.sl.home (Scott Lurndal) - 2023-11-03 16:52 +0000
                Re: [OT] Encryption (Was: Inconsistent...) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 15:12 -0700
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 15:11 -0700
              Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:43 +0000
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:53 -0700
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 20:08 +0000
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 13:12 -0700
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:12 +0000
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 14:16 -0700
                Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:43 +0000
                Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 16:02 -0700
                Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 22:59 +0000
  Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-30 23:52 +0000
    Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 13:45 -0700
    Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 14:29 -0700
    Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 10:10 +0100
      Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 09:52 +0000
        Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 11:31 +0000
          Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 13:52 +0100
            Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 14:07 +0000
              Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 16:53 +0100
                Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 19:15 +0000
                Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-03 10:33 +0100
          Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 20:43 +0000
            Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 13:47 -0700
        Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 13:34 +0100
  Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-11-01 20:32 +0000
    Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:36 +0000
      Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-11-01 21:54 +0000
      Re: Inconsistent... Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-11-09 15:54 -0800
  Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-09 01:16 -0800
  Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-10 21:02 -0800

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