Installation of pygit2 is failing

[johnsamuelwrites]

On running

pip3 install pygit2

I get the following error on Ubuntu 19.10

src/types.h:36:2: error: #error You need a compatible libgit2 version (1.0.x)
       36 | #error You need a compatible libgit2 version (1.0.x)
          |  ^~~~~
    src/types.h:251:5: error: unknown type name ‘git_mailmap’
      251 |     git_mailmap *mailmap;
          |     ^~~~~~~~~~~
    error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

A previous issue suggested installing libgit2-dev and also build-essential libffi-dev python-dev libgit2-dev, but there is no change. Am I missing any particular installation.

Following is the version of libgit installed.

$ ldconfig -p | grep libgit
	libgit2.so.27 (libc6,x86-64) => /lib/x86_64-linux-gnu/libgit2.so.27
	libgit2.so (libc6,x86-64) => /lib/x86_64-linux-gnu/libgit2.so

[omniproc]

You need to get the environment variable LIBGIT2 and it has to point to the binaries of libgit2 version >= 1.0.0. From the error I suppose because you installed libgit2 using your OS repos that libgit2 version is <= 1.0.0. Pygit2 >= 1.2.0 requires libgit2 >= 1.0.0.

Since libgit2 is quite new and thus missing in most repos yet, you might want to compile it on your own:

apt remove libgit2-dev
apt install cmake
# OpenSSL. Used by libgit2. Might be better to build this from source as well?
apt install libssl-dev
# Used by libgit2 to find packages, such like libssh2
apt install pkg-config
git clone --depth=1 -b libssh2-1.9.0 https://github.com/libssh2/libssh2.git ~/libssh2_src
cd ~/libssh2_src
# Important: build as shared library using -DBUILD_SHARED_LIBS=ON
cmake . -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=ON -DCMAKE_INSTALL_PREFIX=~/libssh2
cmake --build . --target install
# move bins to shared system libs folders so they can be found by libgit2
cp -r ~/libssh2/* /usr/bin
cp -r ~/libssh2/* /usr/local
ldconfig
git clone --depth=1 -b v1.0.0 https://github.com/libgit2/libgit2.git ~/libgit2_src
cd ~/libgit2_src
cmake . -DBUILD_CLAR=OFF -DCMAKE_BUILD_TYPE=Release -DEMBED_SSH_PATH=~/libssh2_src -DCMAKE_INSTALL_PREFIX=~/libgit2
cmake --build . --target install
# move bins to shared system libs folders so they can be found when you import pygit2
cp -r ~/libgit2/* /usr/bin
cp -r ~/libgit2/* /usr/local
ldconfig
unset LIBGIT2
python3 -m pip uninstall -y pygit2
python3 -m pip install pygit2

[jdavid]

Actually libgit2 is included in the binary Linux wheels, so don't need for this.

My guess is that you're trying to install latest pygit2 with Python 2, which doesn't work. Since the wheel is not available for Python 2 then it tries to build it, and fails because you have an old version of libgit2.

Your choices are:

• Use the packaged version, that's python3-pygit2 in Ubuntu 19.10
• Use the latest version of pygit2, which includes libgit2. That only works with Python 3.6 or later.

Most Linux users don't need to build pygit2 at all.

[jdavid]

Ok I see now you're using pip3. In any case it's not picking the binary wheel as it should. Maybe it's an old version of Python 3? Only Python 3.6 or later is supported. Or may it be a 32bit system? We only distribute Linux wheels for 64bit platforms.

[jdavid]

Alright, I could test in a Ubuntu 19.10 box. To fix it you need to upgrade pip. For example this works:

pip3 install -U pip
pip install pygit2

[johnsamuelwrites]

Hi @jdavid,

I am using Python 3.7.5

$ python3 --version
Python 3.7.5

and I am using pip3.
I resolved the problem by compiling the source code of libgit2 (similar to the steps given by @M451) and the problem is resolved.

I think, this is a problem that was discovered after the release of libgit2 v1.0.0.

[jdavid]

Ok, it doesn't work with pip 18.1, and it does with pip 19.0+

[jdavid]

Added a warning to the documentation. Thanks for reporting.