Issue #8435 has been updated by nagai (Hidetoshi Nagai).

Status changed from Open to Third Party's Issue

It depends on Ubuntu packages. The patch may be able to avoid the "current" problem, 
but it cannot guarantee that it is available in the next version of Ubuntu.
If the policy of Ubuntu is changed, extconf.rb must check the Tcl/Tk package version of Ubuntu.
I think that it is not a good choice.
Although it may be troble, please use configure options.

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Bug #8435: Can't build tcl/tk extensions after updating Debian/Ubuntu package
https://bugs.ruby-lang.org/issues/8435#change-39989

Author: romuloceccon (Romulo Ceccon)
Status: Third Party's Issue
Priority: Normal
Assignee: nagai (Hidetoshi Nagai)
Category: ext
Target version: current: 2.1.0
ruby -v: ruby 2.1.0dev (2013-05-21 trunk 40883) [x86_64-linux]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


I've recently upgraded my Ubuntu system to 13.04 and tcl8.5-dev and tk8.5-dev were updated as well (to versions 8.5.13-1ubuntu and 8.5.11-2ubuntu4 respectively).

Now I can't build Tcl/Tk Ruby extensions anymore. I was able to reproduce the problem with
  ruby 2.0.0p195 (2013-05-14 revision 40734) [x86_64-linux] and
  ruby 2.1.0dev (2013-05-21 trunk 40883) [x86_64-linux].

Looking at source:/ext/tk/extconf.rb@39974#L376 I see that extconf tries to parse tclConfig.sh and tkConfig.sh, which worked nice previously when those files were ln'ed to the actual configuration files. However, after the update they look like this on my platform:

    $ cat /usr/lib/tclConfig.sh 
    #!/bin/sh
    . /usr/lib/`dpkg-architecture -qDEB_HOST_MULTIARCH`/tclConfig.sh
    $ cat /usr/lib/tkConfig.sh 
    #!/bin/sh
    . /usr/lib/`dpkg-architecture -qDEB_HOST_MULTIARCH`/tkConfig.sh

So the setup fails:

    ...
    Search tclConfig.sh and tkConfig.sh.....................
    WARNING: found "/usr/lib/tclConfig.sh", but cannot find valid Tcl library for the tclConfig.sh. So, ignore it.
    
    WARNING: found "/usr/lib/tkConfig.sh", but cannot find valid Tk library for the tkConfig.sh. So, ignore it.
    ..........
    Fail to find [tclConfig.sh, tkConfig.sh]
    ...

Full 'ruby extconf.rb' output and mkmf.log are attached.


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