Hello,

I want to give multiple native classes (in different mixed mode dlls) access
to a managed output window (for error messages). Therefore I wrote a native
singleton with __declspec (dllexport). I get the following compiler errors:

Error    224    error C3389: __declspec(dllexport) cannot be used with /clr:pure
or /clr:safe   
Error    225    error C4394: 'ErrorHandler::instance' : per-appdomain symbol
should not be marked with __declspec(dllexport)   
Error    226    error C4394: 'private: static ErrorHandler *
ErrorHandler::instance' : per-appdomain symbol should not be marked with
__declspec(dllexport)
Error    228    error C3395: 'ErrorHandler::GetInstance' : __declspec(dllexport)
cannot be applied to a function with the __clrcall calling convention

and the same with the other methods of the class. The dll is definitely not
set to /clr:pure or /clr:safe.

I could not reproduce resp. localize the problem with a test program.

I will attach my class below.

Thanks for your help,

Fabian

<SNIP>

#include <stdlib.h>
#include "vcclr.h"
using namespace DebugTools;
#using <System.Windows.Forms.dll>

#pragma once

class __declspec( dllexport ) ErrorHandler
{
private:
    static ErrorHandler* instance;
    gcroot<FormDebugOutput^> formDebugOutput;

public:
    static ErrorHandler* GetInstance()
    {
        if (instance == NULL)
        {
            instance = new ErrorHandler();
            _onexit(destroyInstance); // A _onexit function is called when the
process exits normally.
        }
        return instance;
    }

    void PrintMessage(char* Source, char* Message)
    {
        if (!formDebugOutput)
        {
            formDebugOutput->PrintMessage((signed char*)Source, (signed char*)Message);
        }
    }

    void SetDebugForm(gcroot<FormDebugOutput^> FormDebugOutput)
    {
        formDebugOutput = FormDebugOutput;
    }

private:
    ErrorHandler()
    {
        formDebugOutput = nullptr;
    }

    static int destroyInstance()
    {
        delete instance;
        instance = NULL;
        return 0;
    }   
};

</SNIP>

FormDebugOutput is a form in a C#-DLL derived from Windows.Forms.Form.