for-loop mutates to an endless-loop

From	"Walter H." <Walter.H-Nntp@mathemainzel.info>
Newsgroups	comp.lang.c
Subject	for-loop mutates to an endless-loop
Date	2020-01-03 13:27 +0100
Organization	Waldi's NNTP Home
Message-ID	<h78q9lF3mhkU1@mid.individual.net> (permalink)

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Hello,

I built a VM with DOS and Turbo Pascal for a mate of mine;

[code]
Program SumDemo;
Var
   nIter : Integer;
   lSum : LongInt;
Begin
   lSum := 0;
   For nIter := -32768 to 32767 Do
     lSum := lSum + nIter;
   WriteLn( 'sum: ', lSum );
End.
[/code]

there I tested above programme; and it worked as exprected; as my 
hardware is new the result came within a second

[output]
sum: -32768
[/output]

then I tried the same in C with several compilers
32-bit, 64-bit Intel, GNU under Linux or Visual C++ under Windows
even QuickC or Turbo C every one built this programme with an endless-loop;

[code]
#include <stdio.h>
int main( int argc, char* argv[ ] )
{
     short int nIter;
     long lSum = 0;
     for ( nIter = -32768; nIter <= 32767; nIter++ )
         lSum += nIter;
     printf( "sum: %ld\n", lSum );
     return 0;
}
[/code]

here the same in old FORTRAN which also worked as expected;

[code]
       PROGRAM SumDemo
       INTEGER*2 nIter
       INTEGER*4 lSum
       lSum = 0
       DO nIter = -32768,32767,1
       lSum = lSum + nIter
       END DO
       WRITE ( *, * ) 'sum: ', lSum
       END
[/code]

where is the mistake in C?

this modified C-programme works as expected,
but looks weired

[code]
#include <stdio.h>
int main( int argc, char* argv[ ] )
{
     short int nIter = -32768;
     long lSum = 0;
     do
     {
         lSum += nIter++;
     }
     while ( nIter > -32768 );
     printf( "sum: %ld\n", lSum );
     return 0;
}
[/code]

what would be the correct way of a for-loop
with the complete range of an integral type?

by the way also with unsigned it is the same ...

[code]
#include <stdio.h>
int main( int argc, char* argv[ ] )
{
     unsigned short int nIter;
     unsigned long lSum = 0;
     for ( nIter = 0; nIter <= 65535; nIter++ )
         lSum += nIter;
     printf( "sum: %lu\n", lSum );
     return 0;
}
[/code]

this strange behaviour also exists with 32-bit or 64-bit like this

[code]
long int i32Iter;
for ( i32Iter = -2147483648; i32Iter <= 2147483647; i32Iter++ )
// ...
[/code]

bzw.

[code]
long long int i64Iter;
for ( i64Iter = -9223372036854775808; i64Iter <= 9223372036854775807; 
i64Iter++ )
// ...
[/code]

with C++ it is the identical problem;

Thanks,
Walter

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for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-03 13:27 +0100
  Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-03 14:01 +0100
  Re: for-loop mutates to an endless-loop Dan Purgert <dan@djph.net> - 2020-01-03 13:18 +0000
    Re: for-loop mutates to an endless-loop James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-03 08:28 -0500
      Re: for-loop mutates to an endless-loop Dan Purgert <dan@djph.net> - 2020-01-03 13:33 +0000
        Re: for-loop mutates to an endless-loop James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-03 21:10 -0500
    Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-03 15:34 +0100
  Re: for-loop mutates to an endless-loop James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-03 08:26 -0500
    Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-04 16:15 +0100
      Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-04 17:17 +0100
      Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 16:20 +0000
        Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-04 18:43 +0100
          Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-04 19:28 +0100
            Re: for-loop mutates to an endless-loop Bart <bc@freeuk.com> - 2020-01-04 18:59 +0000
              Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-05 14:24 +0100
            Re: for-loop mutates to an endless-loop Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-01-04 13:47 -0800
              Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-05 14:26 +0100
              Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-06 20:31 +0100
          Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 22:25 +0000
      Re: for-loop mutates to an endless-loop Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-01-04 14:08 -0800
      Re: for-loop mutates to an endless-loop James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-04 21:32 -0500
        Re: for-loop mutates to an endless-loop scott@slp53.sl.home (Scott Lurndal) - 2020-01-05 21:48 +0000
      Re: for-loop mutates to an endless-loop James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-04 21:43 -0500
  Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 14:47 +0100
    Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-03 14:39 +0000
      Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 15:42 +0100
        Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-03 15:07 +0000
          Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 16:18 +0100
            Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 16:47 +0100
              Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-03 20:41 +0000
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 01:05 +0100
            Re: for-loop mutates to an endless-loop gazelle@shell.xmission.com (Kenny McCormack) - 2020-01-03 18:30 +0000
        Re: for-loop mutates to an endless-loop Robert Wessel <robertwessel2@yahoo.com> - 2020-01-04 00:23 -0600
          Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 08:10 +0100
            Re: for-loop mutates to an endless-loop scott@slp53.sl.home (Scott Lurndal) - 2020-01-04 16:41 +0000
              Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 17:44 +0100
          Re: for-loop mutates to an endless-loop Bart <bc@freeuk.com> - 2020-01-04 11:15 +0000
            Re: for-loop mutates to an endless-loop Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-04 12:33 +0000
              Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-04 15:59 +0100
              Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 16:01 +0100
                Re: for-loop mutates to an endless-loop Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-04 16:04 +0000
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 17:06 +0100
                Re: for-loop mutates to an endless-loop scott@slp53.sl.home (Scott Lurndal) - 2020-01-04 16:42 +0000
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 17:44 +0100
            Re: for-loop mutates to an endless-loop Robert Wessel <robertwessel2@yahoo.com> - 2020-01-04 17:55 -0600
              Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-06 20:43 +0100
                Re: for-loop mutates to an endless-loop scott@slp53.sl.home (Scott Lurndal) - 2020-01-06 19:50 +0000
                Re: for-loop mutates to an endless-loop Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-01-06 15:37 -0500
                Re: for-loop mutates to an endless-loop scott@slp53.sl.home (Scott Lurndal) - 2020-01-06 21:59 +0000
                Re: for-loop mutates to an endless-loop Robert Wessel <robertwessel2@yahoo.com> - 2020-01-06 17:33 -0600
      Re: for-loop mutates to an endless-loop gazelle@shell.xmission.com (Kenny McCormack) - 2020-01-03 18:31 +0000
        Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 01:06 +0100
          Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 01:38 +0000
            Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 08:10 +0100
              Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 16:39 +0000
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 17:41 +0100
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 17:49 +0100
                Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 22:49 +0000
                Re: for-loop mutates to an endless-loop Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-05 03:44 +0100
            Re: for-loop mutates to an endless-loop David Brown <david.brown@hesbynett.no> - 2020-01-04 13:09 +0100
  Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-03 14:28 +0000
    Re: for-loop mutates to an endless-loop jak <nospam@please.ty> - 2020-01-05 00:40 +0100
    Re: for-loop mutates to an endless-loop "Walter H." <Walter.H-Nntp@mathemainzel.info> - 2020-01-06 20:50 +0100
      Re: for-loop mutates to an endless-loop Manfred <noname@add.invalid> - 2020-01-06 21:28 +0100
    Re: for-loop mutates to an endless-loop Manfred <noname@add.invalid> - 2020-01-06 21:02 +0100
    Re: for-loop mutates to an endless-loop Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-11 10:01 -0800
  Re: for-loop mutates to an endless-loop Richard Damon <Richard@Damon-Family.org> - 2020-01-04 16:21 -0500
    Re: for-loop mutates to an endless-loop Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-01-04 22:17 +0000

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