#5257: Rubygems rebuild failed due to wrong expansion of %{_libdir} macro

[Fedora Release Engineering]

#5257: Rubygems rebuild failed due to wrong expansion of %{_libdir} macro
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  Reporter:  vondruch         |      Owner:  rel-eng@…
      Type:  defect           |     Status:  new
 Milestone:  Fedora 18 Alpha  |  Component:  koji
Resolution:                   |   Keywords:
Blocked By:                   |   Blocking:
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Comment (by vondruch):

 Replying to [comment:4 spot]:
 > The problem is that noarch packages need to be valid and correct on
 _all_ possible architectures. If %{_libdir} was evaluated from the build
 env (x86_64), and files end up in %{_libdir} (/usr/lib64), that package
 would install files into a directory on i686 that is unused and for which
 the system runtime would have no reason to look in.
 >
 > The solution is to not use %{_libdir} (or macros that evaluate from
 %{_libdir}) in a noarch package. Period.

 That make sense although it is not obvious. Would be nice if it could be
 mentioned somewhere (I hope I did not missed some part of guidelines :))

 > The isa macro is not defined because we have no idea what the bitsize is
 for a noarch build, nor should we.

 Neither I do care about bit size, I just want to find my library.

 > What you need to do is determine a path for these files that ruby will
 _always_ search/find/locate/use, regardless of architecture, then either
 hardcode that into a macro. An initial look through the ruby config
 suggests that perhaps "rubylibdir" is appropriate. So, maybe define a
 systemwide macro called "%{ruby_sitelib}" which evaluates from the result
 of:
 >
 > {{{
 > ruby -rrbconfig -e 'puts Config::CONFIG["rubylibdir"]'
 > }}}
 >
 > This seems appropriate because /usr/share/$FOO is a universal target
 (remember, all files in a noarch package must be identical on all possible
 architectures), but I don't know Ruby well enough to be sure that this is
 indeed 100% correct. I looked for any pathing including /usr/lib in the
 x86_64 Config output, but there was none.
 >
 > The equivalent for python is %{python_sitelib}, which is hardcoded (by
 the python executable) to:
 > /usr/lib/python2.7/site-packages. The reason this works is because A) It
 is not using %{_libdir} to define this macro and B) python _always_ looks
 in /usr/lib/python2.7/site-packages, regardless of architecture.

 Ok, you proposed solution for Ruby and for Python, but what about other
 noarch packages? I'd like to have some generic solution. Let say
 %{runtime_libdir}, alternatively %{runtime_arch} or whatever you call it
 which could be used universally across all languages etc.

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Ticket URL: <https://fedorahosted.org/rel-eng/ticket/5257#comment:5>
Fedora Release Engineering <http://fedorahosted.org/rel-eng>
Release Engineering for the Fedora Project