cross-build 32bit rundll32'able DLL with mingw

example_dll.cpp

#undef UNICODE
#define UNICODE
#include <windows.h>
#include <stdio.h>

// i686-w64-mingw32-g++ -shared -o ExampleDll.dll example_dll.cpp -Wl,--out-implib,libExampleDll.dll -static -lgcc example_dll.def
//
// example_dll.def:
// EXPORTS
// RunDllMe=RunDllMe@16
//
// rundll32 ExampleDll.dll,RunDllMe

extern "C"
  __stdcall
  void
  CALLBACK
  RunDllMe(HWND, HINSTANCE, wchar_t const*, int)
{
#if 0
    AllocConsole();
    freopen( "CONIN$", "r", stdin );
    freopen( "CONOUT$", "w", stdout );
    freopen( "CONOUT$", "w", stderr );

    DWORD const infoBoxOptions = MB_ICONINFORMATION | MB_SETFOREGROUND;
    MessageBox( 0, L"Before call...", L"DLL message:", infoBoxOptions );
#endif
  for(;;) {
    Sleep(0xffff);
#if 0
    printf("hey hey\n");
#endif
  }
}