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Variable read after for-loop
This is biggest mistake to count on last value of for-loop variable after the loop:
procedure Test;
var i: Integer;
begin
for i:= 1 to 5 do
Writeln(i);
Writeln(i);
end;
It seems you can count on intermediate value on Break
for i:= 1 to 5 do
if i mod 3 = 0 then Break
else Writeln(i);
Writeln(i);
But this is undocumented, you should know if Break was executed and both cases are too danger to rely on due to optimization which can suddenly use a register for loop var.
This is inspired by Peganza Pacal Expert rules.
Customer support service by UserEcho
Delphi itself produces warning
[dcc32 Warning] W1037 FOR-Loop variable 'i' may be undefined after loop
But adding this check to FixInsight still brings a lot of value.
Btw, Delphi doesn't warn against reading loop-var after loop with Break. Even such case goes unnoticed:
for i:= 1 to 5 do
if False then Break
else Writeln(i);
Writeln(i);