<*+ MAIN *>
MODULE hello;

IMPORT InOut;
VAR res: INTEGER;
BEGIN
  res := 10 DIV (-3);
  InOut.WriteInt (res, 5);
  InOut.WriteLn;
END hello.

dia@lenovo:/usr/local/xds/samples/oberon$ xc hello.ob2
XDS Oberon-2 v2.40 [x86, v1.50] - build 03.02.2012
Compiling "hello.ob2"

* [hello.ob2 7.07 E029]
* incompatible types:
    "INT16"
    "whole constant (ZZ)"
  res $:= 10 DIV (-3);

* [hello.ob2 7.13 E107]
* shall not have a value less than 0
  res := 10 $DIV (-3);
errors  2, no warnings, lines   10, time  0.01

<*+ MAIN *>
MODULE hello;

IMPORT InOut;
VAR a, b: INTEGER;
BEGIN
  a := -3;
  b := 10 DIV a;
  InOut.WriteInt (b, 5);  InOut.WriteLn;
END hello.

dia@lenovo:/usr/local/xds/samples/oberon$ xc =m hello.ob2
O2/M2 development system v2.60 TS  (c) 1991-2011 Excelsior, LLC. (build 03.02.2012)
XDS Oberon-2 v2.40 [x86, v1.50] - build 03.02.2012
Compiling "hello.ob2"

* [hello.ob2 8.11 W912]
* wholeDivException will be raised here
  b := 10 $DIV a;
no errors, warnings  1, lines   11, time  0.01
gcc  -o hello hello.o  /usr/local/xds/lib/x86/libts.a /usr/local/xds/lib/x86/libxds.a  -lm -lncurses -m32

dia@lenovo:/usr/local/xds/samples/oberon$ ./hello

#RTS: unhandled exception #6: zero or negative divisor at line 8 of hello.ob2
#RTS: No history available.

LONGINT SYSTEM_DIV(LONGINT x, LONGINT y) // INT64 SYSTEM_DIV(INT64 x, INT64 y)
{
  if (x == 0) return 0;
  if (x >= 0)
    if (y >= 0) {return x/y;}
    else        {return -((x-y-1)/(-y));}
  else
    if (y >= 0) {return -((y-x-1)/y);}
    else        {return (-x)/(-y);}
}

INTEGER SYSTEM_DIV(INTEGER x, INTEGER y)
{
   if (y > 0) {
      if (x < 0) return ~(~x / y);
      else return x / y;
   } else if (y < 0) {
      if (x > 0) return ~((x - 1) / -y);
      else return -x / -y;
   } else {
      __HALT(-5);
   }
}