Devart Forums

Delphi 2009
FB 2.1
DBXIDA 2.50.20

If a TSQLConnection fails to connect because the FB server username/password is incorrect, DBXIBA leaks memory.

Very easily reproduced by deliberately using an incorrect password when connecting to a database.

Here's the report of leaked memory:

An unexpected memory leak has occurred. The unexpected small block leaks are:

1 - 12 bytes: Unknown x 3
13 - 20 bytes: TIBCSQLTransactions x 1, TList x 1, TCRConnections x 2, Unknown x 2
21 - 28 bytes: UnicodeString x 1
29 - 36 bytes: UnicodeString x 1
37 - 44 bytes: TIBCSQLTransaction x 1, UnicodeString x 1
45 - 52 bytes: TGDSDatabaseInfo x 1
53 - 60 bytes: UnicodeString x 1
61 - 68 bytes: TGDSTransaction x 2
69 - 76 bytes: TStringList x 4
77 - 84 bytes: UnicodeString x 2, Unknown x 1
85 - 92 bytes: TIBCSQLConnection x 1
117 - 124 bytes: UnicodeString x 1
173 - 188 bytes: TGDSConnection x 1
221 - 236 bytes: Unknown x 1
1981 - 2172 bytes: Unknown x 1

A successfull connection does not generate the memory leak.

Thank you for information. We are investigating this problem. As soon as we solve the problem we will let you know.

I could not reproduce the problem.
Please try to compose a small sample to demonstrate the problem and send it to dmitryg*devart*com.

No need to send an example - it is absolutely simple to reproduce like this:

uses
SqlExpr, DbxIdaDriverLoader;

procedure TForm1.Button1Click(Sender: TObject);
var
SQLCon: TSQLConnection;
begin
ReportMemoryLeaksOnShutdown := True;

SQLCon := TSQLConnection.Create(nil);
try
SQLCon.DriverName := DbxIdaDriverLoader.sBuiltinDriverName;

SQLCon.LoginPrompt := False;
SQLCon.Params.Clear;
SQLCon.Params.Add('User_Name=' + 'XXX');
SQLCon.Params.Add('Password=' + 'YYY');
SQLCon.Params.Add('Database=' + 'C:\ZZZ.FDB');
try
SQLCon.Open;
except
on E:Exception do
Application.ShowException(E);
end;
finally
SQLCon.Free;
end;

Close;
end;

This is a bug of dbExpress. It does not free the connection handle if an error occurs.

But most of the objects not being freed are Devart classes, so surely you can put in appropriate resource protection to free your own objects - either immediately or at least when shutting down?