Runtime error: application has requested runtime to terminate it in an unusual way - calling C# from C++

I have a C# DLL that uses SQLDMO and I have a C++ program that calls it.  I can run it in the debugger and the code goes through and calls the DLL and executes the function just like I would expect it to but when the function exits I get this error:

---------------------------
Microsoft Visual C++ Runtime Library
---------------------------
Runtime Error!

Program: C:\C# DLL\TestProgram2\Debug\TestProgram2.exe



This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.


---------------------------
OK  
---------------------------


any ideas?
LVL 1
emily_hallAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

ptmcompCommented:
What call conventions are you using? How do you call from C++ to C#?
emily_hallAuthor Commented:
This is my C++ code:

::CoInitialize(NULL);

SetConnectionString(connectionString);
      
_DbClassPtr p;
p.CreateInstance("DatabaseLibrary.DbClass");
m_DLLInterfacePtr = p.GetInterfacePtr();

m_DLLInterfacePtr->loadStoredProcedureDetails(m_connectionString);

loadStoredProcedureDetails returns a bool but I have tried returning void and the same thing happens...
ptmcompCommented:
Is m_connectionString a BSTR? Who allocates the memory and who is deallocating it?
OWASP Proactive Controls

Learn the most important control and control categories that every architect and developer should include in their projects.

emily_hallAuthor Commented:
m_connectionString is a char*.

and that is the code for the whole function - connectionString is passed in.

ptmcompCommented:
I think that's the problem COM usually marhals string as BSTR and not as char*. The process tries to free memory that it doesn't own.
ptmcompCommented:
Did you compile it with UNICODE or ANSI option?

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
emily_hallAuthor Commented:
A coworker of mine actually found the problem but we so far haven't been able to figure out how to fix it.  The problem isn't with that function but with the one that is called after it:

int machineId = m_DLLInterfacePtr->executeStoredProcedure("sp_GetMachineId", m_connectionString, (tagSAFEARRAY *)getMachineId, 3);

the problem is with the 3rd parameter which I typecast to a tagSAFEARRAY* in order to make it compile.  What that is is an array of struct.  On the other side, the C# is expecting an array of struct but it is dying when it tries to pass that through...

emily_hallAuthor Commented:
hey just going through my old questions trying to tidy things up.  thanks for the help.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
C#

From novice to tech pro — start learning today.