Can't install libxml-ruby

I can install version 2.7, but this old version is required by using bundle install. Anyone can help?

dehuang$ sudo gem install libxml-ruby -v ‘2.3.3’

Password:

Building native extensions. This could take a while…

ERROR: Error installing libxml-ruby:

ERROR: Failed to build gem native extension.

/Users/yihuang/.rvm/rubies/ruby-1.9.3-p194/bin/ruby extconf.rb

extconf.rb:17: Use RbConfig instead of obsolete and deprecated Config.

checking for socket() in -lsocket… no

checking for gethostbyname() in -lnsl… no

checking for atan() in -lm… no

checking for atan() in -lm… yes

checking for inflate() in -lz… yes

checking for iconv_open() in -liconv… yes

checking for xmlParseDoc() in -lxml2… yes

checking for libxml/xmlversion.h… yes

creating extconf.h

creating Makefile

make

compiling libxml.c

compiling ruby_xml.c

compiling ruby_xml_attr.c

compiling ruby_xml_attr_decl.c

compiling ruby_xml_attributes.c

compiling ruby_xml_cbg.c

ruby_xml_cbg.c: In function ‘deb_Open’:

ruby_xml_cbg.c:50: warning: implicit conversion shortens 64-bit value into a 32-bit value

compiling ruby_xml_document.c

ruby_xml_document.c: In function ‘rxml_document_canonicalize’:

ruby_xml_document.c:259: warning: implicit conversion shortens 64-bit value into a 32-bit value

ruby_xml_document.c:303: warning: implicit conversion shortens 64-bit value into a 32-bit value

ruby_xml_document.c:334: warning: passing argument 4 of ‘xmlC14NDocDumpMemory’ from incompatible pointer type

ruby_xml_document.c:334: warning: implicit conversion shortens 64-bit value into a 32-bit value

compiling ruby_xml_dtd.c

compiling ruby_xml_encoding.c

compiling ruby_xml_error.c

compiling ruby_xml_html_parser.c

compiling ruby_xml_html_parser_context.c

ruby_xml_html_parser_context.c: In function ‘rxml_html_parser_context_string’:

ruby_xml_html_parser_context.c:235: warning: implicit conversion shortens 64-bit value into a 32-bit value

compiling ruby_xml_html_parser_options.c

compiling ruby_xml_input_cbg.c

ruby_xml_input_cbg.c: In function ‘ic_open’:

ruby_xml_input_cbg.c:49: warning: implicit conversion shortens 64-bit value into a 32-bit value

ruby_xml_input_cbg.c: In function ‘input_callbacks_add_scheme’:

ruby_xml_input_cbg.c:113: warning: implicit conversion shortens 64-bit value into a 32-bit value

compiling ruby_xml_io.c

ruby_xml_io.c: In function ‘rxml_read_callback’:

ruby_xml_io.c:19: warning: implicit conversion shortens 64-bit value into a 32-bit value

compiling ruby_xml_namespace.c

compiling ruby_xml_namespaces.c

compiling ruby_xml_node.c

ruby_xml_node.c: In function ‘rxml_node_new_cdata’:

ruby_xml_node.c:151: warning: implicit conversion shortens 64-bit value into a 32-bit value

ruby_xml_node.c: In function ‘rxml_node_to_s’:

ruby_xml_node.c:622: error: dereferencing pointer to incomplete type

ruby_xml_node.c:624: error: dereferencing pointer to incomplete type

make: *** [ruby_xml_node.o] Error 1

Gem files will remain installed in /Users/yihuang/.rvm/gems/ruby-1.9.3-p194/gems/libxml-ruby-2.3.3 for inspection.

Results logged to /Users/yihuang/.rvm/gems/ruby-1.9.3-p194/gems/libxml-ruby-2.3.3/ext/libxml/gem_make.out

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