[Solved] Cross compiling Irrlicht for Win32 on Linux

[Elmaron]

Hi. I recently tried to cross compile the Irrlicht engine on Linux for the Windows platform (I have no direct access to any windows machine so I am in great need for this). So I opened up the Makefile and tried to add what seems to be necessary to cross compile (replacing the old similar lines if they were present):

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CC = i486-mingw32-gcc
CXX = i486-mingw32-c++
CXXCPP = i486-mingw32-c++ -E
AS = i486-mingw32-as
AR = i486-mingw32-ar

I also removed the #ifdef NDEBUG condition so I always get a release build (poor me doesn't know how to tell make to define some value and that was therefore the faster solution ) and added -D__GNUWIN32__ as mingw didn't seem to define this and I ran into crtdb.h - or how that MSVC debugging solution is called - issues, because the compilation process wanted that file.

So it kinda went smoothly through (this is the very short description of a lot of hassle to get all the Makefile lines above together and finally arrive at this point ) and seemed to compile fine:

http://pastebin.com/m4c9be4dd (this was simply too long to include it here)

But then I attempted to link my application to it/compile my application with it and ran into the following error:

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bash-4.0$ make wcomp
cd src && i486-mingw32-c++ game.cpp -o ../GAME.EXE -L../irrlichtsvn_w/lib/Linux -mwindows -I../irrlichtsvn_w/include -I/usr/X11R6/include -I../../bullet-2.74/src/ ../../bulletw/src/.libs/libbulletdynamics.a ../../bulletw/src/.libs/libbulletmath.a ../../bulletw/src/.libs/libbulletcollision.a -lIrrlicht -DWIN
/tmp/cc6wpc5m.o:game.cpp:(.text+0xa5a3): undefined reference to `__imp__createDeviceEx'
collect2: ld returned 1 exit status
make: *** [wcomp] Error 1
bash-4.0$

I already tried around a lot with guys in the chat, making sure irrlicht headers & source code versions are the same (this is Irrlicht 1.6 SVN 2586) and checked paths twice, the lib is truly located at ../irrlichtsvn_w/lib/Linux:

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bash-4.0$ ls ../irrlichtsvn_w/lib/Linux/
libIrrlicht.a

Also, nm -D on libIrrlicht.a gives strange output. I was told that this wouldn't help this case at all but meh, just in case it gives someone _any_ clue that could help solving the problem:

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nm: CLMTSMeshFileLoader.o: File format not recognized
nm: CMY3DMeshFileLoader.o: File format not recognized

...long continuing list

I really hope someone coming across this post can help.

PS: Did you ever check out the great cross compilation that comes with the bullet physics lib? You can simply do ./configure --host=i486-mingw32 and then do the usual make and it just runs smoothly as you'd be doing a normal compile (apart from some missing glut headers and stuff, but that's much easier and straightforward to fix as my issues with irrlicht now that leave me completely clueless!).

It would be really nice if irrlicht's Makefile would also develop some similar assistance for cross compiling people like me (just an idea)

[hybrid]

You're not supposed to change the Makefile. Just use command line environment variables like this:
CXX=i486-mingw32-c++ CC=i486-mingw32-gcc make all_win32

This line will provide all the necessary setup to cross-compile Irrlicht. The same holds for the example makefiles. Runs out-of-the box for me.

[Elmaron]

I now compiled it with the default Makefile again, using this line:

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CXX=i486-mingw32-c++ CC=i486-mingw32-gcc make staticlib_win32

When attempting to link the result to my app, I get again:

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cd src && i486-mingw32-c++ game.cpp -o ../GAME.EXE -L../irrlichtsvn_w/lib/Linux -mwindows -I../irrlichtsvn_w/include -I/usr/X11R6/include -I../../bullet-2.74/src/ ../../bulletw/src/.libs/libbulletdynamics.a ../../bulletw/src/.libs/libbulletmath.a ../../bulletw/src/.libs/libbulletcollision.a -lIrrlicht -DWIN
/tmp/ccnfMhRi.o:game.cpp:(.text+0xa5a3): undefined reference to `__imp__createDeviceEx'
collect2: ld returned 1 exit status
make: *** [wcomp] Error 1
bash-4.0$

Edit:
Also tried your original line now:

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CXX=i486-mingw32-c++ CC=i486-mingw32-gcc make all_win32

Same result.

[Elmaron]

I feel dumb now... as you can see with the compiler command line I was simply still taking the lib out of lib/Linux where it was located with my modified Makefile. Ofc it still didn't work then
So thanks a lot for your hint hybridOL, it works now Yay!