I'm trying to compile Caffe on an Ubuntu 14.04, but I still get the following error:
/usr/bin/ld: cannot find -lboost_python-py35
/usr/bin/ld: cannot find -lpython3.5m
collect2: error: ld returned 1 exit status
make: *** [.build_release/lib/libcaffe.so] Error 1
Does anyone have an idea what this would be?
Yes - you did not install packages with the headers of these libraries on the system, so you can compile something with them.
Whenever you compile a package - and sometimes a "pip install" command in pure Python will compile, you need to have all the necessary libraries in your system.
There is no exact rule of what packages you need a priori, and names can change from one Linux distribution to another. In Ubuntu and Debian, these are packages ending with "-dev", (and in Redhat / fedora, "-devel").
In my case, it should be sufficient to type sudo apt-get install python3-dev at the prompt and then the same for the libboost-all-dev package. I'm not in Ubuntu here - so I do not know the name of the package apra libbosst Python you need - for this use the command apt-cache search boost|grep python - and see what is listed that is closest to libboost-python3-dev - with that name, repeat the sudo apt-get install <nome> command.
With these packages on the system, try compiling again.