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Building for Python3.6 - ImportError: undefined symbol: PyClass_Type

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp, python
Domain
backend

Research direction

Start by reproducing the reported sequence with ./bootstrap --with-python-version=3.6 and ./b2 --with-python --debug-configuration, then inspect which library the libs/pythion/example/tutorial loads. Compare that result with the reported libboost_python-py27.so.1.65.1 and PyClass_Type error; done means the tutorial uses the Python 3 build without the Python 2 symbol failure.

Written by the indexing model from the issue text.

Description

Hi,

I am trying to build boost for use with Python 3 but I am having some troubles.
I call ./bootstrap --with-python-version=3.6 and then ./b2 --with-python --debug-configuration which correctly shows python 3.6 is being used and the python component is being built.

When running the $BOOST_ROOT/libs/pythion/example/tutorial, I get the following error:
ImportError: /usr/lib/x86_64-linux-gnu/libboost_python-py27.so.1.65.1: undefined symbol: PyClass_Type

This shows the python2.7 shared object is being used and I am aware that the PyClass_Type is a Python 2 type. So somehow the program is still being built with python 2 despite me specifying Python 3.
I have tried several iterations of cleaning and building all, just in case something had not been built properly, but I still get the same issue.

Am I missing something ?

Thanks

Dominant language
C++
Stars
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Forks
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Avg merge
11h 22m
Merged PRs (30d)
2

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