python3 has wrong LINKFORSHARED in module sysconfig

[count0]

Please always follow these steps:

• Confirmed this is a problem with brew installing one, specific Homebrew/homebrew-core formula (not cask or tap) and not every time you run brew? If it's a general brew problem please file this issue at https://github.com/Homebrew/brew/issues/new. If it's a brew cask problem please file this issue at https://github.com/caskroom/homebrew-cask/issues/new. If it's a tap (e.g. Homebrew/homebrew-php) problem please file this issue at the tap.
• Ran brew update and retried your prior step?
• Ran brew doctor, fixed all issues and retried your prior step?
• Ran brew gist-logs <formula> (where <formula> is the name of the formula that failed) and included the output link?
• If brew gist-logs didn't work: ran brew config and brew doctor and included their output with your issue?

This is a regression of: Homebrew/legacy-homebrew#37923

When using python3, and running:

import distutils.sysconfig
distutils.sysconfig.get_config_var('LINKFORSHARED')

it returns '-Wl,-stack_size,1000000 -framework CoreFoundation Python.framework/Versions/3.4/Python'

Like we observe in https://github.com/Homebrew/homebrew-science/issues/6461, automake builds like graph-tool calls this method. Then it looks for Python.framework/Versions/3.4/Python in /System/Library/Frameworks. This directory does not exist since it is in #{HOMEBREW_PREFIX}/Cellar/python3/3.4.3/Frameworks instead.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[songololo]

Not stale

[ilovezfs]

@zmwangx any idea what's going on here?

[zmwangx]

@ilovezfs Not sure. We appear to be setting the variable correctly, but Python's not picking it up:

$ /usr/local/Cellar/python3/3.6.4/bin/python3 -c 'import distutils.sysconfig; print(distutils.sysconfig.get_makefile_filename()); print(distutils.sysconfig.get_config_var("LINKFORSHARED"))'
/usr/local/Cellar/python3/3.6.4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/config-3.6m-darwin/Makefile
-Wl,-stack_size,1000000  -framework CoreFoundation Python.framework/Versions/3.6/Python
$ grep -E '^(LINKFORSHARED|PYTHONFRAMEWORKINSTALLDIR)' /usr/local/Cellar/python3/3.6.4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/config-3.6m-darwin/Makefile
LINKFORSHARED=	-Wl,-stack_size,1000000  -framework CoreFoundation $(PYTHONFRAMEWORKINSTALLDIR)/Versions/$(VERSION)/$(PYTHONFRAMEWORK)
PYTHONFRAMEWORKINSTALLDIR= /usr/local/opt/python3/Frameworks/Python.framework

I'll test a non-Homebrew build later to see if this is brew-specific. So Tim's no longer available?

[ilovezfs]

@zmwangx formally, no. Homebrew/brew@e504caa#diff-04c6e90faac2675aa89e2176d2eec7d8

But we could always try pinging him if you think it's necessary :)

[zmwangx]

Yeah I know he formally stepped down, just wondering if his activities stopped completely.

[ilovezfs]

He's still participating on IRC but hasn't opened any PRs of late.

[zmwangx]

This should be fixed by #22103.

[ilovezfs]

@count0 @Shongololo @tommyjiang This should be fixed now, thanks to @zmwangx, if you brew update && brew reinstall python3

[songololo]

@count0 @ilovezfs @zmwangx I can confirm all is now working with graph-tool on python version 3