Will Bolden Will Bolden - 4 months ago 96
Linux Question

Linking error: DSO missing from command line

I am rather new to Linux (using Ubuntu 14.04 LTS 64bit), coming from Windows, and am attempting to port over an existing CUDA project of mine.

When linking via

/usr/local/cuda/bin/nvcc -arch=compute_30 -code=sm_30,compute_30 -o Main.o Display.o FileUtil.o Timer.o NeuralNetwork.o -L/usr/lib -L/usr/local/lib -L/usr/lib/x86_64-linux-gnu -L/usr/local/cuda/lib64 -lGLEW -lglfw3 -lGL -lGLU -lcuda -lcudart


I encounter the following error:

/usr/bin/ld: /usr/local/lib/libglfw3.a(x11_clipboard.c.o): undefined reference to symbol 'XConvertSelection'
//usr/lib/x86_64-linux-gnu/libX11.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make: *** [CUDANN] Error 1


The answer seems closely related to the solutions in this post (Strange linking error: DSO missing from command line), though given my inexperience with Linux I was unable to adapt them to my own problem.

Any ideas on what the problem could be?

Here is the full output during compilation: https://gist.github.com/wbolden/857eddd11e4dcb915c02

And here is my attempt at a Makefile:
https://gist.github.com/wbolden/135033daae04ed0d8cf3

Answer

Hopefully this will be of help to those, like me, who are new to Linux and don't find anything related to Linux to be particularly obvious.

As noted by talonmies, I am not able to link indirectly and as such need to specify any additional libraries required by the libraries I am using. That is to say, if I link library A, which requires libraries B and C, I need to link all three libraries for the program to link correctly.

To find what other libraries were needed I used the pkg-config command, for which I found a guide here. Running pkg-config --print-requires --print-requires-private glfw3 gave the following output, which is the list of packages required by glfw3.

x11
xrandr
xi
xxf86vm
gl

I was then able to find what libraries I needed to include by running pkg-config --libs, followed by the name of the library. For example, pkg-config --libs x11 yielded -lX11.

Note: you can pass multiple items to pkg-config as input, so running

pkg-config --libs $(pkg-config --print-requires --print-requires-private glfw3)

will print out all the additional libraries you need to link (-lX11 -lXrandr -lXi -lXxf86vm -lGL).

My program now links successfully, I hope this helpful to anyone with a similar problem.