Issue #1728 has been updated by Christian Höltje. I talked with a friend and I realized I'm not explaining this very well. Let me try again. The reason --format-executable should default to on is because the binaries created by "gem" have the name of the "ruby" tied to that version of "gem". Here's two uses cases in full: ----use case 1----------------------- I install ruby 1.8. I use "./configure" when compiling it. The binaries are in /usr/bin/ and do not have a suffix. I decide I want to work on ruby 1.9.1 as well. I use "./configure --program-suffix=19" when compiling it. The binaries are also in /usr/bin but all end with "19", such as "/usr/bin/ruby19". Lets say I ZenTest for 1.8: $ gem install ZenTest This creates /usr/bin/autotest. This executable is intimately tied to ruby 1.8; it begins with "#!/usr/bin/ruby -ws" -- it cannot be used for ruby 1.9 (yet) because the libraries are not installed in ruby 1.9 and the executable it points to is the 1.8 executable. Now lets say I want to install autotest for ruby 1.9: $ gem19 install ZenTest By default, no new binaries are created since they already exists. The executable /usr/bin/autotest is *still* tied to ruby 1.8. This causes confusion by the user; they just installed autotest for ruby 1.9 but it still is running ruby 1.8. ----------------------------------- ----use case 2----------------------- My system administrator installs ruby 1.8 using "./configure" with no arguments. My system administrator installs ruby 1.9.1 using "./configure --program-suffix=19" I (a non-system-administrator) wants to install ZenTest for both: $ gem install ZenTest [output showing it is installed to ~/.gem] $ gem19 install ZenTest [output showing it is installed to ~/.gem] So now I have two "autotest" binaries: ~/.gem/ruby/1.8/bin/autotest and ~/.gem/ruby/1.9.1/bin/autotest If my PATH includes both, then which "autotest" I get depends on my PATH order. The only way I can distinguish between the two executables is by changing my PATH on the fly. Not very useful if I want to be able to easily switch between both versions to verify it works in both versions of Ruby. ----------------------------------- I think that without --format-executable as a default, this is too confusing for a normal user. I agree that a --no-format-executable option should be kept around, though. Choice is good. Ciao! ---------------------------------------- http://redmine.ruby-lang.org/issues/show/1728 ---------------------------------------- http://redmine.ruby-lang.org