Patch for Ruby 2.1.1

a.md

ruby-install -p https://gist.githubusercontent.com/judofyr/11175629/raw/2f22144e3ca261e9e989fcb9a205b473c208007f/patch.diff ruby 2.1.1

patch.diff

diff --git a/ext/readline/readline.c b/ext/readline/readline.c
--- a/ext/readline/readline.c
+++ b/ext/readline/readline.c
@@ -1974,7 +1974,7 @@
 
     rl_attempted_completion_function = readline_attempted_completion_function;
 #if defined(HAVE_RL_PRE_INPUT_HOOK)
-    rl_pre_input_hook = (Function *)readline_pre_input_hook;
+    rl_pre_input_hook = (rl_hook_func_t *)readline_pre_input_hook;
 #endif
 #ifdef HAVE_RL_CATCH_SIGNALS
     rl_catch_signals = 0;
diff --git a/ext/readline/extconf.rb b/ext/readline/extconf.rb
--- a/ext/readline/extconf.rb
+++ b/ext/readline/extconf.rb
@@ -19,6 +19,10 @@
   return super(func, headers)
 end
 
+def readline.have_type(type)
+  return super(type, headers)
+end
+
 dir_config('curses')
 dir_config('ncurses')
 dir_config('termcap')
@@ -94,4 +98,8 @@
 readline.have_func("rl_redisplay")
 readline.have_func("rl_insert_text")
 readline.have_func("rl_delete_text")
+unless readline.have_type("rl_hook_func_t")
+  $DEFS << "-Drl_hook_func_t=Function"
+end
+
 create_makefile("readline")