title: Error when installing Ruby 1.9.3 on Mac OS X Lion
body: <p>I'm trying to install Ruby 1.9.3 and Rails on MAC OS X Lion. (My Xcode is version 4.3)
  (I've installed Rails 3.2.2)</p>
  
  <p>No matter if I use:</p>
  
  <pre><code>rvm install 1.9.3 --with-gcc=clang
  </code></pre>
  
  <p>or:</p>
  
  <pre><code>rvm install 1.9.3
  </code></pre>
  
  <p>My terminal shows:</p>
  
  <pre><code>Error running 'make ', please read /Users/AlexHo/.rvm/log/ruby-1.9.3-p125/make.log
  There has been an error while running make. Halting the installation.
  </code></pre>
  
  <p>Has anyone encountered the same situation?</p>
  
  <hr>
  
  <pre><code>AlexHo@Nien-Yi-Hos-MacBook:~$ rvm install 1.9.3
  Fetching yaml-0.1.4.tar.gz to /Users/AlexHo/.rvm/archives
  Extracting yaml-0.1.4.tar.gz to /Users/AlexHo/.rvm/src
  Configuring yaml in /Users/AlexHo/.rvm/src/yaml-0.1.4.
  Compiling yaml in /Users/AlexHo/.rvm/src/yaml-0.1.4.
  Installing yaml to /Users/AlexHo/.rvm/usr
  Installing Ruby from source to: /Users/AlexHo/.rvm/rubies/ruby-1.9.3-p125, this may take a while depending on your cpu(s)...
  
  ruby-1.9.3-p125 - #fetching 
  ruby-1.9.3-p125 - #extracted to /Users/AlexHo/.rvm/src/ruby-1.9.3-p125 (already extracted)
  ruby-1.9.3-p125 - #configuring 
  ruby-1.9.3-p125 - #compiling 
  Error running 'make ', please read /Users/AlexHo/.rvm/log/ruby-1.9.3-p125/make.log
  There has been an error while running make. Halting the installation.
  </code></pre>
  
  <hr>
  
  <pre><code>AlexHo@Nien-Yi-Hos-MacBook:~$ cat /Users/AlexHo/.rvm/log/ruby-1.9.3-p125/make.log
  [2012-03-03 04:15:53] make 
          CC = clang
          LD = ld
          LDSHARED = clang -dynamiclib
          CFLAGS = -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Werror=pointer-arith -Werror=write-strings -Werror=declaration-after-statement -Werror=shorten-64-to-32 -Werror=implicit-function-declaration  -fno-common -pipe 
      XCFLAGS = -include ruby/config.h -include ruby/missing.h -fvisibility=hidden -DRUBY_EXPORT
      CPPFLAGS = -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -I. -I.ext/include/x86_64-darwin11.3.0 -I./include -I.
      DLDFLAGS = -Wl,-undefined,dynamic_lookup -Wl,-multiply_defined,suppress -Wl,-flat_namespace -install_name /Users/AlexHo/.rvm/rubies/ruby-1.9.3-p125/lib/libruby.1.9.1.dylib -current_version 1.9.1 -compatibility_version 1.9.1 -Wl,-unexported_symbol,_Init_* -Wl,-unexported_symbol,*_threadptr_*  -Wl,-u,_objc_msgSend   
      SOLIBS = 
  linking miniruby
  rbconfig.rb unchanged
  generating enc.mk
  generating prelude.c
  compiling prelude.c
  linking static-library libruby.1.9.1-static.a
  linking shared-library libruby.1.9.1.dylib
  generating encdb.h
  encdb.h unchanged
  making enc
  make[1]: Nothing to be done for `enc'.
  making srcs under enc
  make[1]: Nothing to be done for `srcs'.
  generating transdb.h
  transdb.h unchanged
  making trans
  make[1]: Nothing to be done for `./enc/trans'.
  making encs
  installing default bug libraries
  installing default resize libraries
  installing default bug libraries
  installing default bug libraries
  installing default funcall libraries
  installing default dot.dot libraries
  installing default old_thread_select libraries
  installing default numhash libraries
  installing default string libraries
  installing default wait_for_single_fd libraries
  installing default bigdecimal libraries
  installing default continuation libraries
  installing default coverage libraries
  installing default curses libraries
  installing default date_core libraries
  make[2]: Nothing to be done for `all'.
  installing digest libraries
  installing default digest libraries
  installing default bubblebabble libraries
  installing default md5 libraries
  installing default rmd160 libraries
  installing default sha1 libraries
  installing default sha2 libraries
  installing dl libraries
  installing default dl libraries
  installing default callback libraries
  make[2]: Nothing to be done for `all'.
  installing default etc libraries
  installing default fcntl libraries
  installing default fiber libraries
  installing default fiddle libraries
  make[2]: Nothing to be done for `all'.
  installing default iconv libraries
  installing default console libraries
  installing default nonblock libraries
  installing default wait libraries
  installing default libraries
  installing default generator libraries
  installing default parser libraries
  installing default complex libraries
  installing default rational libraries
  installing default nkf libraries
  installing default objspace libraries
  installing default openssl libraries
  installing default pathname libraries
  installing default psych libraries
  installing default pty libraries
  installing default cparse libraries
  compiling readline.c
  readline.c:1499:9: error: use of undeclared identifier 'username_completion_function'; did you mean 'rl_username_completion_function'?
                                      rl_username_completion_function);
                                      ^
  readline.c:69:42: note: instantiated from:
  # define rl_username_completion_function username_completion_function
                                           ^
  /usr/local/include/readline/readline.h:449:14: note: 'rl_username_completion_function' declared here
  extern char *rl_username_completion_function PARAMS((const char *, int));
               ^
      1 error generated.
      make[2]: *** [readline.o] Error 1
      make[1]: *** [ext/readline/all] Error 2
      make: *** [build-ext] Error 2
  </code></pre>