Compile the Python interpreter statically?

Question

I'm building a special-purpose embedded Python interpreter and want to avoid having dependencies on dynamic libraries so I want to compile the interpreter with static libs instead (eg libc.a not libc.so).

I would also like to statically link all dynamic libraries that are part of the Python standard library as well. I know this can be done using Freeze.py, but is there an alternative so that it can be done in one step?

Thanks, Jeremy

Answer 1

Using freeze doesn't prevent doing it all in one run (no matter what approach you use, you will need multiple build steps - e.g. many compiler invocations). First, you edit Modules/Setup to include all extension modules that you want. Next, you build Python, getting libpythonxy.a. Then, you run freeze, getting a number of C files and a config.c. You compile these as well, and integrate them into libpythonxy.a (or create a separate library).

You do all this once, for each architecture and Python version you want to integrate. When building your application, you only link with libpythonxy.a, and the library that freeze has produced.

Answer 2

You can try with ELF STATIFIER. I've been used it before and it works fairly well. I just had problems with it in a couple of cases and then I had to use another similar program called Ermine. Unfortunately this one is a commercial program.

Answer 3

I found this (mainly concerning static compilation of Python modules):

http://bytes.com/groups/python/23235-build-static-python-executable-linux

Which describes a file used for configuration located here:

/Modules/Setup

If this file isn't present, it can be created by copying:

<Python_Source>/Modules/Setup.dist

The Setup file has tons of documentation in it and the README included with the source offers lots of good compilation information as well.

I haven't tried compiling yet, but I think with these resources, I should be successful when I try. I will post my results as a comment here.

-- UPDATES --

To get a pure-static python executable, you must also configure as follows:

./configure LDFLAGS="-static -static-libgcc" CPPFLAGS="-static"

Once you build with these flags enabled, you will likely get lots of warnings about "renaming because library isn't present". This means that you have not configured "Modules/Setup" correctly and need to:

a) add a single line (near the top) like this:

*static*

(that's STAR the word "static" and STAR with no spaces)

b) uncomment all modules that you want to be available statically (such as math, array, etc...)

You may also need to add specific linker flags (as mentioned in the link I posted above). My experience so far has been that the libraries are working without modification.

It may also be helpful to run make with as follows:

make 2>1 | grep 'renaming'

This will show all modules that are failing to compile due to being statically linked.