From: "drbrain (Eric Hodel)" Date: 2013-02-22T07:14:59+09:00 Subject: [ruby-core:52636] [ruby-trunk - Bug #7897] rubygems 2.0 has an incompatibility about installation of extension libraries if gem package does not contain lib directory Issue #7897 has been updated by drbrain (Eric Hodel). As Vit Ondruch has noted, it seems to be a bug in the Makefile generated by mkmf.rb as ruby 1.9.3 without Murata-san's patch correctly installs lib/msgpack.bundle. Nobu, can you check it? Just to be safe, I committed Murata-san's patch and will open a backport request. ---------------------------------------- Bug #7897: rubygems 2.0 has an incompatibility about installation of extension libraries if gem package does not contain lib directory https://bugs.ruby-lang.org/issues/7897#change-36720 Author: mrkn (Kenta Murata) Status: Closed Priority: Urgent Assignee: drbrain (Eric Hodel) Category: lib Target version: 2.0.0 ruby -v: ruby 2.0.0dev (2013-02-08 trunk 39161) [x86_64-darwin11.4.2] Hi, rubygems 2.0 has an incompatibility about installation of extension libraries. If a gem package does not contain lib directory, an extension library file is copied as a file named "lib". You can reproduce this problem by installing msgpack version 0.4.7. -- http://bugs.ruby-lang.org/