Re: global struct variables in DLL?

From:

"Lisa Pearlson" <no@spam.plz>

Newsgroups:

microsoft.public.vc.language

Date:

Tue, 26 May 2009 22:39:15 +0200

Message-ID:

<F8D6B22C-E88A-4FAD-9B7A-D9336D0629DE@microsoft.com>

I have the same issue with a more simple construction that I have always
used, but is also not behaving as expected:

HINSTANCE g_hInstance = NULL; // global

BOOL APIENTRY DllMain( HANDLE hModule, DWORD dwReason, LPVOID lpReserved)
{
    switch (dwReason)
    {
    case DLL_PROCESS_ATTACH:
        g_hInst = (HINSTANCE) hModule; // when debugging, hModule is
NON-NULL, but g_hInst is 0x00000000 (unused???)
        break;
    }
    return TRUE;
}

Perhaps g_hInst is fine, but debugger can not evaluate it?

Lisa

"Lisa Pearlson" <no@spam.plz> wrote in message
news:0123B124-C60D-458B-8743-A254084480ED@microsoft.com...

Hi guys,

I'm really confused about something here.
I have a DLL that exports a function "Test()", and in this function I want
to use a global variable:

This is my code:

#include <string>

typedef struct _MYSTRUCT {
   wstring t;
   int i;
   _MYSTRUCT() {
       t = TEXT("Some Text");
       i = 10;
   }
} MYSTRUCT, *LPMYSTRUCT;

MYSTRUCT g_mystruct; // global variable;

// exported function;
void Test()
{
   ASSERT( g_mystruct.i == 10 ); // fails

   MYSTRUCT locstruct;
   ASSERT( g_mystruct == 10 ); // succeeds
}

The constructor DOES get called when program runs, but as soon as it
enters the function, the global variable is uninitialized.

I don't understand above behaviour.
The DLL is Loaded and exported function is called from within the same
thread.

Can someone enlighten me?

Lisa