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reply "shuji" <cravstar hotmail.com> writes:
Can someone help me with this:
I have a library which I try to import from D
//funcs.lib
//windows includes...
HWND hwnd;
int setHWND(HWND extHwnd){
	hwnd = extHwnd;
	return 0;
}

//main.d
pragma(lib, "gdi32.lib");
import core.runtime;
import core.sys.windows.windows;
extern (C++) {
	int setHWND(HWND hwnd);
}
int main(int argc, char **argv) {
//windows initializers
	setHWND(hwnd);
	return 0;
}

but when I try to import that function this comes:
    Error 42: Symbol Undefined ?setHWND  YAHPAX Z (int cdecl
setHWND(void *))
--- errorlevel 1

it seems like I cannot use HWND directly.
Jun 30 2013
parent reply "Simen Kjaeraas" <simen.kjaras gmail.com> writes:
On Sun, 30 Jun 2013 20:24:17 +0200, shuji <cravstar hotmail.com> wrote:



 int setHWND(HWND extHwnd){
 	hwnd = extHwnd;
 	return 0;
 }


And:


 extern (C++) {
 	int setHWND(HWND hwnd);
 }



See how these are different? One of them is an extern (C++) function, the  
other is a D function.

In other words, this should work:

//funcs.lib
//windows includes...
HWND hwnd;
extern (C++) { // This line!
int setHWND(HWND extHwnd){
	hwnd = extHwnd;
	return 0;
}
}

//main.d
pragma(lib, "gdi32.lib");
import core.runtime;
import core.sys.windows.windows;
extern (C++) {
	int setHWND(HWND hwnd);
}
int main(int argc, char **argv) {
//windows initializers
	setHWND(hwnd);
	return 0;
}



-- 
Simen
Jun 30 2013
parent reply "shuji" <cravstar hotmail.com> writes:
this code is in a .cpp file
//funcs.lib
//windows includes...
HWND hwnd;
int setHWND(HWND extHwnd){
	hwnd = extHwnd;
	return 0;
}

So im trying to import from D like this. I dont think I can 
implement this line in C++
extern (C++) {}
Jun 30 2013
parent reply "Anthony Goins" <neontotem gmail.com> writes:
On Sunday, 30 June 2013 at 19:03:13 UTC, shuji wrote:

 this code is in a .cpp file
 //funcs.lib
 //windows includes...
 HWND hwnd;
 int setHWND(HWND extHwnd){
 	hwnd = extHwnd;
 	return 0;
 }

 So im trying to import from D like this. I dont think I can 
 implement this line in C++
 extern (C++) {}


I'm probably the most unqualified person to offer help but are 
you sure you are linking with funcs.lib (assuming setHWND is 
defined there)
Jun 30 2013
parent reply "shuji" <cravstar hotmail.com> writes:
On Sunday, 30 June 2013 at 20:04:12 UTC, Anthony Goins wrote:

 On Sunday, 30 June 2013 at 19:03:13 UTC, shuji wrote:

 this code is in a .cpp file
 //funcs.lib
 //windows includes...
 HWND hwnd;
 int setHWND(HWND extHwnd){
 	hwnd = extHwnd;
 	return 0;
 }

 So im trying to import from D like this. I dont think I can 
 implement this line in C++
 extern (C++) {}


 I'm probably the most unqualified person to offer help but are 
 you sure you are linking with funcs.lib (assuming setHWND is 
 defined there)


yes, i have called other functions in the same file correctly.

PD I can call a function with void* as receiving paremeter:
//main.d
extern (C++) {
	int setHWND(void* ehwnd);
}
//mylib.cpp
int setmyHWND(void* exthwnd){
	hwnd = (HWND)exthwnd;
	return 0;
}
and then cast on C++ to HWND, but I think it would be better to 
send the parameter correctly as HWND.
Jun 30 2013
parent David <d dav1d.de> writes:
Am 30.06.2013 22:20, schrieb shuji:

 On Sunday, 30 June 2013 at 20:04:12 UTC, Anthony Goins wrote:

 On Sunday, 30 June 2013 at 19:03:13 UTC, shuji wrote:

 this code is in a .cpp file
 //funcs.lib
 //windows includes...
 HWND hwnd;
 int setHWND(HWND extHwnd){
     hwnd = extHwnd;
     return 0;
 }

 So im trying to import from D like this. I dont think I can implement
 this line in C++
 extern (C++) {}


 I'm probably the most unqualified person to offer help but are you
 sure you are linking with funcs.lib (assuming setHWND is defined there)


 
 yes, i have called other functions in the same file correctly.
 
 PD I can call a function with void* as receiving paremeter:
 //main.d
 extern (C++) {
     int setHWND(void* ehwnd);
 }
 //mylib.cpp
 int setmyHWND(void* exthwnd){
     hwnd = (HWND)exthwnd;
     return 0;
 }
 and then cast on C++ to HWND, but I think it would be better to send the
 parameter correctly as HWND.


make sure the HWND parameter is on both "sides" the same (it has to get
mangled correctly!). I don't know if HWND is an opaque struct, if it is,
this might get you into trouble.

--- Cut here, I looked into core.sys.windows.windows:


---
alias void *HANDLE;
alias HANDLE HWND;
---

That is the problem, on the C++-Side HWND is not of type void* hence it
gets mangled differently, you need to get DMD mangle it the same as the
C++ compiler does...

The problem is (I just looked it up) HWND is *basically* void*

All typedefs:
PVOID = void*
HANDLE = PVOID
HWND = HANDLE

So you have to "emulate" a typedef to get the correct mangling... Maybe
start messing arround with structs?

struct HWND;
etc.


Maybe you could also try to use the deprecated "typedef" in D. Neither
of these soloutions are really great. I would consider this another bug
on the extern(C++) list.
Jun 30 2013