The following program compiles but crashes with an integer range error when it gets to the comparison:

{$R+}
var
  a : cardinal;
  b : longint;
begin
  a := 0;
  b := -1;
  if a > b then writeln ('OK');
end.

Am I missing something, or is this a compiler bug?

Mark

Compile with warnings on, i.e. -vw .

This is a bug. Added it as tb0447 to the testsuite.

Workaround is to use int64(a) in the comparison

OK, int64 works around that one....but what about this one, which crashes on the call to inc (I guess inc can't handle a 64 bit parameter):

{$R+}
var
  a : ansistring;
  b : cardinal;
begin
  a := 'hello';
  b := -1;
  inc (b, int64(length (a)));
end.

the b:=-1 is not valid. The 1.1 compiler gives a correct error for it:
p.pp(7,8) Error: range check error while evaluating constants

It isn't considered as a bug in 1.0.x, see also my message about the warning.

Workaround is to use int64(a) in the comparison