[Quickfix-developers] **** VERY IMPORTANT ***** Crashes in QuickFIX compiled with MS VC++ 6.0

[Pasquale d'A. <pas...@ga...>]

My application (compiled using Visual Studio 6.0) is affected by random =
corruptions of data as other developers have mentioned.

I found a recent Microsoft article about STL string use in =
multithreading environment:
http://support.microsoft.com/default.aspx?scid=3Dkb;en-us;813810
that can explain such a behaviour.

In QuickFIX, common fields data, such as BeginString, SenderCompID, =
TargetCompID, are filled in message by copying them from the original =
values in Session::m_sessionID (see the function Session::fill() ); =
concurrently, the same values are accessed by the incoming messages =
thread to make validity checks (see the functions =
Session::isCorrectCompID() and Session::next(const Message& message) ).

Sometimes, especially during periods of heavy traffic, the reference =
counting of the strings stored in Session::m_sessionID might be updated =
wrongly as the above article explains. In these cases, the strings =
stored in Session::m_sessionID might be released and following accesses =
will cause memory corruptions and crashes.

I'm going to protect all the simultaneous reads to shared std::string's =
with a mutex.

What do you think about?

Regards.
Pasquale d'Aloise