A Problem (?) With For -- To -- Do

[Curt Carpenter]

This is a dumb mistake, but I wonder if FPC should issue an error when it occurs?  (Or perhaps it DOES issue one if you have the compiler switches set correctly, and I don't?)

procedure foo(n: integer);
var i: byte;
begin
  for i := 0 to N do <something>;
end;

If the argument N >255, the for--to--do statement seems to simply not execute at all, with no warning to let you know that the variable i really needs to be an integer, not a byte. 

Does range checking turned on catch this?

[Blaazen]

If the argument N >255, the for--to--do statement seems to simply not execute at all, with no warning to let you know that the variable i really needs to be an integer, not a byte.

Not true, it behaves like (N and 255).

Code: [Select]

begin
  n:=257;
  for i := 0 to N do <something>;
end;will be like

Code: [Select]

for i:=0 to 1 doI think this is by design, it is not a bug.

Does range checking turned on catch this?

It raises exception here.

[Curt Carpenter]

Ah -- interesting.  Thanks.