[Rdkit-devel] The 2018.03 release, python 2.7, and Windows

[Greg L. <gre...@gm...>]

Dear all,

In finalizing the details for the 2018.03.1 release, I hit a problem with
python v2.7 on Windows that is likely to result in there being no conda
builds available for the Windows version of python 2.7.

The problem is that extension modules for python 2.7 “are supposed to be”
built with a 10+ year old version of visual C++. This ancient compiler
can’t handle modern C++ and thus can no longer build the RDKit. It is
possible, though somewhat risky, to use other compilers, but conda-build
makes that challenging.

I have already spent a fair amount of time on this without making
significant progress, so I’m going to give up with apologies to anyone who
is still using Python 2.7 on Windows. I may have end up having alternate
ideas to try out later, but if anyone else knows how to force recent
versions of conda-build to use a more modern compiler on Windows, I’d love
to hear about it.

A reminder for people who are still using python 2.7: it's a very good idea
to read this and start figuring out a plan for migrating to Python 3:
https://python3statement.org


 Best,
-greg