Error locating libclang.so on Debian/Ubuntu systems

[rhdunn]

On Debian and Ubuntu systems, libclang is provided by the libclang1 package. This installs /usr/lib/libclang.so.1 on amd64 and i386 systems, not /usr/lib/libclang.so (see e.g. http://packages.ubuntu.com/raring/amd64/libclang1/filelist).

This means that running cldoc I get the error:

Traceback (most recent call last):
  File "/usr/local/bin/cldoc", line 5, in <module>
    cldoc.run()
  File "/usr/local/lib/python2.7/dist-packages/cldoc/__init__.py", line 152, in run
    generate(opts, cxxflags)
  File "/usr/local/lib/python2.7/dist-packages/cldoc/__init__.py", line 23, in generate
t.process()
  File "/usr/local/lib/python2.7/dist-packages/cldoc/tree.py", line 200, in process
    index = cindex.Index.create()
  File "/usr/local/lib/python2.7/dist-packages/cldoc/clang/cindex.py", line 1862, in create
    return Index(conf.lib.clang_createIndex(excludeDecls, 0))
  File "/usr/local/lib/python2.7/dist-packages/cldoc/clang/cindex.py", line 153, in __get__
    value = self.wrapped(instance)
  File "/usr/local/lib/python2.7/dist-packages/cldoc/clang/cindex.py", line 3096, in lib
lib = self.get_cindex_library()
  File "/usr/local/lib/python2.7/dist-packages/cldoc/clang/cindex.py", line 3127, in get_cindex_library
    raise LibclangError(msg)
cldoc.clang.cindex.LibclangError: libclang.so: cannot open shared object file: No such file or directory. To provide a path to libclang use Config.set_library_path() or Config.set_library_file().

[jessevdk]

You will need to install libclang-dev instead.

[rhdunn]

Strictly speaking, libclang-dev should only be used if you are building something that is interfacing with clang. When running the built program, it should depend on libclang1. That is, you don't need to install the *-dev packages of other components just to use the library that component provides.

Thanks for this info -- it would be worth mentioning it in the getting started page.

[jessevdk]

I've mentioned it now. I know that the .so is for development normally. The problem is with the clang python bindings which only looks for the unversioned .so. I'll see if this can be fixed in the future.

[refi64]

Why not use something like this:

from ctypes.util import find_library
# ...
Config.set_library_file(find_library('clang'))

[jessevdk]

I'm using this now, at least for linux. It seems to be working fine.

[cosmicexplorer]

Hey, this didn't work for me. I had to manually add the line Config.set_library_path("/usr/lib/llvm-3.4/lib") to line 3100 of /usr/local/lib/python2.7/dist-packages/cldoc/clang/cindex.py to make it stop complaining. Setting LD_LIBRARY_PATH in the shell didn't help, so I had to make that change. This was on Ubuntu 14.04.

[grvlbit]

I encountered the same issue as @cosmicexplorer. The problem with Ubuntu (at least 14.04) seems to be the name of the libclang.so file. In /usr/lib/x86_64-linux-gnu/ the file is called libclang.so.1 which is then not found by cldoc causing the error.

Therefore I propose a less restrictive lib file search to fix this issue. Since I am not that fluent in Python I cannot provide the patch myself.

A workaround is creating a symlink in /usr/lib/x86_64-linux-gnu/ as ln -s libclang.so.1 libclang.so

[Wallacoloo]

I was faced with the same issue on Ubuntu 14.10 after installing via pip. gujans symlink solution worked for me. Unless this has been fixed in the github code and not yet published to pip, I think this issue should be reopened.

[jessevdk]

Can you try with current master and let me know if that solves the issue?

[Wallacoloo]

Tested with master and it works just fine. Sorry for the trouble.

[jessevdk]

I will make a new release soon so this gets picked up.

[lzuwei]

I am having some issues on MacOSX Yosemite,
cldoc is complaining about libclang.dylib

it is located in /Library/Developer/CommandLineTools/usr/lib/libclang.dylib on my machine.
Is there an easy way to point to this?

cldoc.clang.cindex.LibclangError: dlopen(libclang.dylib, 6): image not found. To provide a path to libclang use Config.set_library_path() or Config.set_library_file().

[jessevdk]

This should have been fixed in 1.7.

[tsteinholz]

I installed cldoc via the pip yesterday. It is installed in /usr/local/bin/cldoc but I get the same issue with not finding clang. I have both clang and the dev version of clang. I have attempted the system link trick (which didn't work) and my project is up to date. What can I do?