* ruby.c (rubylib_mangled_path, rubylib_mangled_path2): return
	  VALUE instead of a pointer to static buffer.
	* ruby.c (push_include_cygwin): fixed buffer overflow.
	  [ruby-dev:31297]
	* ruby.c (ruby_init_loadpath): not convert built-in paths.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8_6@13204 b2dd03c8-39d4-4d8f-98ff-823fe69b080e