How to install Python from source on Debian GNU/Linux

Posted on: 31 10 2019 by Panta in Linux

The default Python 3 version on Debian is 3.7, and the latest Python release is 3.8.

To install the latest Python version, you need to compile it from source code.

Before compilation process, first you need to install a few required tools and dependences needed for building Python from source.

$ sudo apt install build-essential wget libssl-dev zlib1g-dev libbz2-dev liblzma-dev libffi-dev tcl-dev libgdbm-dev libsqlite3-dev libreadline-dev tk tk-dev libmpdec-dev

Next, download the latest Python release from python.org web site:

$ wget https://www.python.org/ftp/python/3.8.0/Python-3.8.0.tgz

Verify and unpack the downloaded archive file:

$ md5sum xvzf Python-3.8.0.tgz
e18a9d1a0a6d858b9787e03fc6fdaa20  Python-3.8.0.tgz

$ tar xvzf Python-3.8.0.tgz

The next step is to run the configure command to prepare the build:

$ cd Python-3.8.0

$ ./configure --enable-loadable-sqlite-extensions --enable-shared --with-lto --enable-optimizations --with-system-expat --with-system-ffi --with-computed-gotos --with-system-libmpdec --enable-ipv6 CC=x86_64-linux-gnu-gcc

Use --with-pydebug flag if you want to build Python with debug info

Use --with-dbmliborder=bdb:gdbm flag if you want to build Python with DBM Module against Berkeley DB (GDBM)

After the configure script finishes its job, you can build Python using the make command:

$ make -j 8

Replace 8 with the number of cores that your CPU have.

$ grep -c processor /proc/cpuinfo
8

When the compilation process finishes, in order to install Python, use the following command:

$ sudo make altinstall

Note: We use make altinstall instead of the make install command, because we don't want to overwrite our system python installation.

The new Python executable will be installed in /usr/local/bin directory. You can run it executing the python3.8 command in your terminal:

$ python3.8

Python 3.8.0 (default, Oct 15 2019, 10:08:48)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>> import sysconfig
>>>
>>> sysconfig.get_python_version()
'3.8'
>>>
>>> sysconfig.get_path('stdlib')
'/usr/local/lib/python3.8'
>>>
>>> sysconfig.get_platform()
'linux-x86_64'
>>>
sysconfig.get_config_var('CONFIG_ARGS')
"'--enable-loadable-sqlite-extensions' '--enable-shared' '--with-lto' '--enable-optimizations' '--with-system-expat' '--with-system-ffi' '--with-computed-gotos' '--with-system-libmpdec' '--enable-ipv6' 'CC=x86_64-linux-gnu-gcc'"

If python complains that can not load the shared library libpython3.8.so.1.0, you'll need to create a symbolic link to the /usr/local/lib/libpython3.8.so.1.0 library:

$ sudo ln -s /usr/local/lib/libpython3.8.so.1.0 /usr/lib/libpython3.8.so.1.0

Then, verify that the library is properly loaded:

$ ldd /usr/local/bin/python3.8
libpython3.8.so.1.0 => /usr/local/lib/libpython3.8.so.1.0 (0x00007fae8b790000)