Traversing Clang's AST with python

A simple guide on how to use libclang to travers clang's AST via python

Steps for Linux

Tested On Ubuntu

Install clang

Make sure the clang is installed. Otherwise, run the command below to install clang

$ sudo apt-get install clang

Create a link to libclan.so

Clang's python binding library looks for libclang.so

First, make sure that the libclang.so is available, just check where it is located?

$ whereis libclang.so

If nothing is returned, that means libclang.so is not available.

If libclang is not linked properly, an error will be thrown. Something like this:

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().

By default, libclang.so is located in this directory (or somewhere similar):

/usr/lib/x86_64-linux-gnu

find the libclang-\<version>.so.1 in this directory, and link it to the libclang.so by running the following command

$ sudo ln -s libclang-10.so.1 libclang.so

Setting up the clang python library

Go to this URL and copy the clang folder. Past the clang folder to the lib folder of your python interpreter. If you are not sure about where python is installed, just run the following python code snippet to find the location of python interpreter.

import sys
print(sys.executable)

Running sample files

sample-hello.cpp is just a very simple Hello World c++ program. We will create an AST for this file.

Simply run the ASTwithClang.py to see some information of the sample-hello. abstract syntax tree.

Windows Issue

Note, I have tried the steps mentioned above on Windows. I always ran into

TranslationUnitLoadError("Error parsing translation unit.")

And still could not find a way around this issue.