RedCloth fails to install

gistfile1.txt

Installing RedCloth (4.0.2) 
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

    /Users/benlieb/.rvm/rubies/ruby-2.0.0-p247/bin/ruby extconf.rb 
creating Makefile

make "DESTDIR="
compiling redcloth_attributes.c
ext/redcloth_scan/redcloth_attributes.c: In function ‘redcloth_attribute_parser’:
ext/redcloth_scan/redcloth_attributes.c:445: warning: implicit conversion shortens 64-bit value into a 32-bit value
ext/redcloth_scan/redcloth_attributes.c:468: warning: implicit conversion shortens 64-bit value into a 32-bit value
ext/redcloth_scan/redcloth_attributes.rl:6: warning: ISO C90 forbids mixed declarations and code
ext/redcloth_scan/redcloth_attributes.rl:3: warning: ISO C90 forbids mixed declarations and code
ext/redcloth_scan/redcloth_attributes.rl: In function ‘redcloth_attributes’:
ext/redcloth_scan/redcloth_attributes.rl:67: warning: ISO C90 forbids mixed declarations and code
ext/redcloth_scan/redcloth_attributes.rl:68: error: ‘struct RString’ has no member named ‘ptr’
ext/redcloth_scan/redcloth_attributes.rl:68: error: ‘struct RString’ has no member named ‘ptr’
ext/redcloth_scan/redcloth_attributes.rl:68: error: ‘struct RString’ has no member named ‘len’
ext/redcloth_scan/redcloth_attributes.rl: In function ‘redcloth_link_attributes’:
ext/redcloth_scan/redcloth_attributes.rl:76: warning: ISO C90 forbids mixed declarations and code
ext/redcloth_scan/redcloth_attributes.rl:77: error: ‘struct RString’ has no member named ‘ptr’
ext/redcloth_scan/redcloth_attributes.rl:77: error: ‘struct RString’ has no member named ‘ptr’
ext/redcloth_scan/redcloth_attributes.rl:77: error: ‘struct RString’ has no member named ‘len’
make: *** [redcloth_attributes.o] Error 1


Gem files will remain installed in /Users/benlieb/.rvm/gems/[email protected]_rails_4/gems/RedCloth-4.0.2 for inspection.
Results logged to /Users/benlieb/.rvm/gems/[email protected]_rails_4/gems/RedCloth-4.0.2/ext/redcloth_scan/gem_make.out

An error occurred while installing RedCloth (4.0.2), and Bundler cannot continue.
Make sure that `gem install RedCloth -v '4.0.2'` succeeds before bundling.