My system has the install binary installed in /usr/bin, but the rbconfig.rb file in /usr/lib/ruby/1.8/$ARCH gives CONFIG["INSTALL"] = '/bin/install -c'. This causes mkmf to use the wrong location when it generates Makefiles (i.e., for gems). I noticed this when installing hpricot via a gem. Reproducible: Always Steps to Reproduce: 1. gem install hpricot
*** This bug has been marked as a duplicate of bug 159922 ***