[Bug modula2/114929] New: for loop fails to iterate down to zero if a cardinal type (unsigned type) is used with a step of -1.

[gaius at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114929

            Bug ID: 114929
           Summary: for loop fails to iterate down to zero if a cardinal
                    type (unsigned type) is used with a step of -1.
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: modula2
          Assignee: gaius at gcc dot gnu.org
          Reporter: gaius at gcc dot gnu.org
  Target Milestone: ---

An example of the bug follows:

MODULE testforloopzero ;

FROM libc IMPORT printf, exit ;


(*
   test -
*)

PROCEDURE test ;
VAR
   i, n,
   count: CARDINAL ;
BEGIN
   n := 5 ;
   count := 0 ;
   FOR i := n TO 0 BY -1 DO
      printf ("i = %d, count = %d\n", i, count);
      INC (count)
   END ;
   IF count = 6
   THEN
      printf ("for loop counting down passed\n")
   ELSE
      printf ("for loop counting down failed\n") ;
      exit (1)
   END
END test ;


BEGIN
   test
END testforloopzero.

$ gm2 testforloopzero.mod
$ ./a.out

i = 5, count = 0
for loop counting down failed