Before when?

  Microsoft(R) MS-DOS(R) Version 6.22
               (C)Copyright Microsoft Corp 1981-1994.
  
  C:\TMP>type foo.c
  void main() {
      long q = 0;
      q = 0/q;
  }
  
  C:\TMP>cl /Od foo.c
  Microsoft (R) Optimizing Compiler Version 5.10
  Copyright (C) Microsoft Corp 1984, 1985, 1986, 1987, 1988. All rights reserved.
  
  [...]
  
  C:\TMP>foo

  run-time error R6003
  - integer divide by 0
  
  C:\TMP>type bar.c
  void main() {
      long far *p = 0;
      long q = 0;
      *p = 0;
      q = 0/q;
  }
  
  C:\TMP>cl /Od bar.c

  [...]

  C:\TMP>bar