Comparison always produces the Same Result (CSR)

Description:

Using information about the possible ranges of operands' values, CSR can detect logical expressions that are always evaluated to the same value (true or false).

Incorrect:

procedure handleEvent(e:Event);
begin
    if e <> nil then 
    begin
        ...
        if e = nil then
        begin
            // always false
            ...
        end;
    end;
end;