我在Mac 64位中收到此错误,并在机器上安装了xcode.
Building native extensions. This could take a while...
ERROR: Error installing ffi:
ERROR: Failed to build gem native extension.
/Users/jreddy/.rvm/rubies/ruby-1.8.7-p302/bin/ruby extconf.rb
checking for ffi.h in /usr/local/include... no
checking for rb_thread_blocking_region()... no
checking for ruby_thread_has_gvl_p()... no
checking for ruby_native_thread_p()... no
checking for rb_thread_call_with_gvl()... no
creating extconf.h
creating Makefile
make
sh: make: command not found