Re: [boost] [boostorg/python] Building against multiple python implementations broken on 1.70 (#262)

Subject: Re: [boost] [boostorg/python] Building against multiple python implementations broken on 1.70 (#262)
From: Peter Dimov (pdimov_at_[hidden])
Date: 2019-04-15 20:37:38

Stefan Seefeld wrote:

> Right. So what's your suggestion / conclusion for to resolve this ?

I'm working on it. I could use a little help.

What is the correct way to configure Boost.Build's `python` on Travis 
Xenial, which supposedly has Python 2.7.15, 3.6.7, and 3.7.1 preinstalled?

https://docs.travis-ci.com/user/reference/xenial/#python-support

I tried putting

    using python : 2.7 ;
    using python : 3.6 ;
    using python : 3.7 ;

in ~/user-config.jam, but that doesn't seem to work. With 
`python=2.7,3.6,3.7` I get

/home/travis/build/boostorg/boost-root/tools/build/src/build/feature.jam:491: 
in feature.validate-value-string from module feature
error: "3.6" is not a known value of feature <python>
error: legal values: "2.7"
/home/travis/build/boostorg/boost-root/tools/build/src/build/property.jam:345: 
in validate1 from module property
/home/travis/build/boostorg/boost-root/tools/build/src/build/property.jam:371: 
in property.validate from module property
/home/travis/build/boostorg/boost-root/tools/build/src/build/build-request.jam:271: 
in convert-command-line-element from module build-request
/home/travis/build/boostorg/boost-root/tools/build/src/build/build-request.jam:222: 
in build-request.convert-command-line-elements from module build-request
/home/travis/build/boostorg/boost-root/tools/build/src/build-system.jam:774: 
in load from module build-system
/home/travis/build/boostorg/boost-root/tools/build/src/kernel/modules.jam:295: 
in import from module modules
/home/travis/build/boostorg/boost-root/tools/build/src/kernel/bootstrap.jam:139: 
in boost-build from module
/home/travis/build/boostorg/boost-root/boost-build.jam:17: in module scope 
from module