Issue #9276 has been updated by postmodern (Hal Brodigan). It appears MRI builds the ruby executable in the root of trunk, not in the bin/ directory where chruby expects it to be. Until this is fixed, you will have to install trunk somewhere (~/.rubies/ or append the installation dir to RUBIES). ---------------------------------------- Bug #9276: "RUBY_FREE_MIN is obsolete. Use RUBY_GC_HEAP_FREE_SLOTS instead" warning should not be issued when both ENV vars are set. https://bugs.ruby-lang.org/issues/9276#change-43922 Author: myronmarston (Myron Marston) Status: Assigned Priority: Normal Assignee: naruse (Yui NARUSE) Category: core Target version: 2.1.0 ruby -v: ruby 2.1.0dev (2013-12-20 trunk 44301) [x86_64-darwin12.0] Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN, 2.1: UNKNOWN Trying out ruby 2.1.0-rc1, I keep getting this warning. I understand why, and I've updated my ~/.zshrc to set RUBY_GC_HEAP_FREE_SLOTS for ruby 2.1, but I need to keep `RUBY_GC_HEAP_FREE_SLOTS` set for projects running on earlier versions. Ideally, this warning would only be emitted when RUBY_FREE_MIN is set and RUBY_GC_HEAP_FREE_SLOTS is not set. If RUBY_GC_HEAP_FREE_SLOTS is set, the programmer clearly knows that's the ENV var to use for 2.1, and likely needs to keep RUBY_FREE_MIN in place for running code against older rubies. After all, having RUBY_FREE_MIN set on 2.1 doesn't cause any problems, right? -- http://bugs.ruby-lang.org/