#include <stdio.h>
#include <assert.h>
#ifdef _WIN32
#include <windows.h>
#else
#include <dlfcn.h>
#endif

#if defined _WIN32 || defined __CYGWIN__
  #define DLL_PUBLIC __declspec(dllexport)
#else
  #if defined __GNUC__
    #define DLL_PUBLIC __attribute__ ((visibility("default")))
  #else
    #pragma message ("Compiler does not support symbol visibility.")
    #define DLL_PUBLIC
  #endif
#endif

typedef int (*fptr) (void);

int DLL_PUBLIC
func_from_executable(void)
{
	return 42;
}

int
main(int argc, char **argv)
{
	int expected, actual;
	fptr importedfunc;

	// noop
	if ((argc = 0)) {
	}

#ifdef _WIN32
	HMODULE h = LoadLibraryA(argv[1]);
#else
	void *h = dlopen(argv[1], RTLD_NOW);
	if (!h) {
		fprintf(stderr, "failed to load '%s': %s\n", argv[1], dlerror());
	}
#endif
	assert(h != NULL);

#ifdef _WIN32
	importedfunc = (fptr)GetProcAddress(h, "func");
#else
	*(void **)(&importedfunc) = dlsym(h, "func");
#endif
	assert(importedfunc != NULL);
	assert(importedfunc != func_from_executable);

	actual = (*importedfunc)();
	expected = func_from_executable();
	assert(actual == expected);

#ifdef _WIN32
	FreeLibrary(h);
#else
	dlclose(h);
#endif

	return 0;
}
