BcdDivide function behave differently in Delphi XE and XE2
DelphiDelphi XeDelphi Xe2Delphi Problem Overview
FmtBcd.pas
has been extensively revised rewritten in Delphi XE2. In one of my projects, I have a case that uses a division operation on two Bcd
values, but the two versions yield different results. In the worst case, the Delphi XE2 may throw a Bcd overflow error
.
Example: Running the following code in Delphi XE2 console apps:
var A, B, C, D: TBcd;
begin
A := StrToBcd('1');
B := StrToBcd('3');
BcdDivide(A, B, C);
WriteLn(BcdToStr(C));
try
BcdMultiply(C, C, D);
WriteLn(BcdToStr(D));
except
on E: Exception do
WriteLn(E.Message);
end;
ReadLn;
end.
Output of the above will be:
0.333333333333333333333333333333333333333333333333333333333333333
BCD overflow
The variable C
contains a Bcd Value with 63 decimal places of specificity. Performing a second BcdMultiply
operation on variable C
will cause a Bcd overflow error
.
However, to run the same code in Delphi XE yields the following result without any exception prompt:
0.3333333333
0.11111111108888888889
Could anyone please suggest a best-practice method for resolving this problem?
Delphi Solutions
Solution 1 - Delphi
The code in the question produces the expected output in XE2 update 4. Note that update 3 produces the bad output and so clearly the fix arrived with update 4. Also, XE3 produces the expected output.