Compiling a dll with g++

Question

I've been trying to compile this projet on windows with g++: https://github.com/newhouseb/openvr-c

My command lines:

g++ -c  -std=gnu++0x -DBUILDING_OPENVR_C openvr_c.cpp openvr_c.h
g++ -shared -o openvr_c.dll openvr_c.o  -std=gnu++0x -Wl,--out-implib,openvr_api.dll -L. -lopenvr_api

When i run the second line i get these errors:

openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext10CheckClearEv[__ZN2vr14COpenVRContext10CheckClearEv]+0x12): undefined reference to _imp__VR_GetInitToken' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext10CheckClearEv[__ZN2vr14COpenVRContext10CheckClearEv]+0x33): undefined reference to_imp__VR_GetInitToken' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext8VRSystemEv[__ZN2vr14COpenVRContext8VRSystemEv]+0x2b): undefined reference to _imp__VR_GetGenericInterface' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext11VRChaperoneEv[__ZN2vr14COpenVRContext11VRChaperoneEv]+0x2c): undefined reference to_imp__VR_GetGenericInterface' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext16VRChaperoneSetupEv[__ZN2vr14COpenVRContext16VRChaperoneSetupEv]+0x2c): undefined reference to _imp__VR_GetGenericInterface' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext12VRCompositorEv[__ZN2vr14COpenVRContext12VRCompositorEv]+0x2c): undefined reference to_imp__VR_GetGenericInterface' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext9VROverlayEv[__ZN2vr14COpenVRContext9VROverlayEv]+0x2c): undefined reference to _imp__VR_GetGenericInterface' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr14COpenVRContext14VRRenderModelsEv[__ZN2vr14COpenVRContext14VRRenderModelsEv]+0x2c): more undefined references to_imp__VR_GetGenericInterface' follow openvr_c.o:openvr_c.cpp:(.text$_ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE[__ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE]+0x23): undefined reference to _imp__VR_InitInternal' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE[__ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE]+0x4c): undefined reference to_imp__VR_IsInterfaceVersionValid' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE[__ZN2vr7VR_InitEPNS_12EVRInitErrorENS_18EVRApplicationTypeE]+0x61): undefined reference to _imp__VR_ShutdownInternal' openvr_c.o:openvr_c.cpp:(.text$_ZN2vr11VR_ShutdownEv[__ZN2vr11VR_ShutdownEv]+0x7): undefined reference to_imp__VR_ShutdownInternal' collect2.exe: error: ld returned 1 exit status

I don't understand what are these errors,

Can someone enlighten me ?

This project is a set of C bindings to OpenVR. You need to link it against an OpenVR version built with gcc. — n. m. could be an AI, Jun 27 '16 at 08:35
OpenVR is closed sources, i think it is build with visual studio. If I want to compile the binding i will have to use the same compiler ? — Tribes, Jun 27 '16 at 13:55
Yes, you have to use the same compiler. g++ and VS have very different ABIs. The name mangling is different, the object layout is different, the standard library implementations are totally different... — n. m. could be an AI, Jun 27 '16 at 14:07
Weird, it looks like the guy that made the binding is using clang — Tribes, Jun 27 '16 at 16:17
They say clang on Windows can be made compatible with MSVC but I'm not familiar with this mode of operation. Try clang-cl as the compiler (with cl-style command line options). — n. m. could be an AI, Jun 27 '16 at 16:19
You need to link it against openvr_api.dll. You may have destroyed it with --out-implib,openvr_api.dll option. — n. m. could be an AI, Jun 27 '16 at 16:35
I managed to compile it with g++ but now I don't find the functions from my header file ^^' — Tribes, Jun 28 '16 at 16:25

score 0 · Answer 1 · edited May 23 '17 at 11:45

0

This looks like a lot of errors coming from your linker. Make sure you link to your dependencies properly.

What is an undefined reference/unresolved external symbol error and how do I fix it?

edited May 23 '17 at 11:45

Community

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answered Jun 27 '16 at 07:49

Ivan Rubinson

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Why is there a dot after the L? – Ivan Rubinson Jun 27 '16 at 08:40
Because the dll to include is in the same directory – Tribes Jun 28 '16 at 16:28

Compiling a dll with g++

1 Answers1