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Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?)

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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:

> antispam@math.uni.wroc.pl writes:
>
>> Lynn McGuire <lynnmcguire5@gmail.com> wrote:
>>
>>> I doubt that any modern C/C++ compilers refuse to take any legal
>>> C/C++ code.  I would not be surprised that modern C/C++ compilers
>>> detect certain benchmarks
>>
>> Some time ago I posted here a simple C program.  It looks legal
>> (nobody here objected to legality of this program).  In principle
>> compiler should generate pretty small executable, but it looks
>> that no existing compiler can handle that program.  One can say
>> that compiler does not "reject" the program, simply compiler runs
>> out of memory.  But for the user effect is the same:  compiler
>> will not handle legal program.
>
> And the answer is the same as before.  The C language is
> infinitely large (and indeed must be if it is to be Turing
> complete).  Compilers are programs;  no program can deal with
> unboundedly large inputs (not counting the vanishingly small
> fraction of programs whose output set is finite rather than
> infinite).  No competent person expects a compiler (or indeed any
> non-trivial program) to be able to handle unboundedly large
> inputs.  A program that is unable to handle a large input simply
> because of its size is not "refusing" to handle the input, and
> anyone who says otherwise is just being obtuse.

But the program was not particularly large.  Instead, the program
required a large amount of compile-time processing which the standard
/could/ have deemed to be not strictly conforming by, say, putting a
limit on the number of tokens permitted in the result of a macro
expansion.  The standard does not do that, so there are small, strictly
conforming programs that one can't reasonably expect to be processed.

Also, I think the reference to C being Turing complete is a red herring.
C could be defined in such as way that valid inputs to the compiler are
always "small" and never require unbounded processing without
compromising the language's completeness.  There need not be any
language feature that can incur exponential (let along unbounded)
compile-time costs for a language to the Turing compete.

C++ has this issue in spades because the template sub-language is Turing
complete.

-- 
Ben.

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Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) KP2 KP2 <jungletrain@outlook.com> - 2022-12-10 13:06 -0800
  Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lynn McGuire <lynnmcguire5@gmail.com> - 2022-12-10 20:57 -0600
    Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lynn McGuire <lynnmcguire5@gmail.com> - 2022-12-10 22:57 -0600
    Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) antispam@math.uni.wroc.pl - 2022-12-11 20:31 +0000
      Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Robert Latest <boblatest@yahoo.com> - 2022-12-12 14:39 +0000
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) antispam@math.uni.wroc.pl - 2022-12-13 12:15 +0000
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-13 16:23 +0000
      Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-26 05:20 -0800
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-26 14:37 +0000
          Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-26 10:30 -0800
            Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-27 16:45 +0000
              Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-27 19:38 -0800
                Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-29 02:09 +0000
                Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-29 19:56 -0800
  Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) antispam@math.uni.wroc.pl - 2022-12-11 20:12 +0000
    Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lynn McGuire <lynnmcguire5@gmail.com> - 2022-12-12 14:33 -0600
      Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) scott@slp53.sl.home (Scott Lurndal) - 2022-12-12 21:12 +0000
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-12 16:09 -0800
  Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Jack Lemmon <invalid@invalid.net> - 2022-12-12 20:30 +0000
    Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lynn McGuire <lynnmcguire5@gmail.com> - 2022-12-12 15:20 -0600
    Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2022-12-12 21:28 +0000
      Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) scott@slp53.sl.home (Scott Lurndal) - 2022-12-12 22:39 +0000
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2022-12-12 22:49 +0000
          Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) "minf...@arcor.de" <minforth@arcor.de> - 2022-12-31 04:01 -0800
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-12 15:56 -0800
          Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) scott@slp53.sl.home (Scott Lurndal) - 2022-12-13 14:55 +0000
            Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) David Brown <david.brown@hesbynett.no> - 2022-12-13 16:26 +0100
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) David Brown <david.brown@hesbynett.no> - 2022-12-13 14:50 +0100
        Re: Limitation of MS-DOS C compiler? (was Re: Should I convert FORTRAN code to C?) Anton Shepelev <anton.txt@g{oogle}mail.com> - 2022-12-13 18:56 +0300

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