Issue with "decrementing for loops"

[peterwvj]

The code-generator wrongly assumes that all for loops increment their loop counter. This issue can be demonstrated using the following model:

class A

operations

public op : () ==> nat
op () ==
(
  dcl c : nat := 10;
	for i = 10 to 5 by -1 do
	  c := c - 1;
	
	return c;
);

end A

To clarify, new A().op() returns 4 as expected, whereas the equivalent C expressions returns 10.