gistfile1.txt

C:\Users\Luis>gem install ffi --pre --platform=ruby
Fetching: ffi-1.0.12.rc3.gem (100%)
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing ffi:
        ERROR: Failed to build gem native extension.

        C:/Ruby193/bin/ruby.exe extconf.rb
checking for ffi.h... no
checking for ffi.h in /usr/local/include... no
checking for rb_thread_blocking_region()... yes
checking for ruby_native_thread_p()... yes
checking for rb_thread_call_with_gvl()... yes
creating extconf.h
creating Makefile

make
generating ffi_c-i386-mingw32.def
Configuring libffi
/bin/sh: ..//c/Ruby193/lib/ruby/gems/1.9.1/gems/ffi-1.0.12.rc3/ext/ffi_c/libffi/configure: No such file or directory
make: *** ["/c/Ruby193/lib/ruby/gems/1.9.1/gems/ffi-1.0.12.rc3/ext/ffi_c/libffi"/.libs/libffi_convenience.a] Error 127


Gem files will remain installed in C:/Ruby193/lib/ruby/gems/1.9.1/gems/ffi-1.0.12.rc3 for inspection.
Results logged to C:/Ruby193/lib/ruby/gems/1.9.1/gems/ffi-1.0.12.rc3/ext/ffi_c/gem_make.out