Nie znaleziono biblioteki dla błędu -lgmp podczas instalacji Railsów na El Capitan (Mac OS 10.11.1 (15B42))

Question

Podczas instalacji Rails na El Capitan (Mac OS X 10.11.1) na Ruby v2.2.2, otrzymałem następujące błąd:

ERROR: Error installing nokogiri: 
    ERROR: Failed to build gem native extension. 

    /Users/jon/.rvm/rubies/ruby-2.2.2/bin/ruby -r ./siteconf20151117-26799-ux15fd.rb extconf.rb --use-system-libraries 
checking if the C compiler accepts ... *** extconf.rb failed *** 
Could not create Makefile due to some reason, probably lack of necessary 
libraries and/or headers. Check the mkmf.log file for more details. You may 
need configuration options. 

a plik mkmf.log miał:

$ cat /Users/jon/.rvm/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/extensions/x86_64-darwin-14/2.2.0/nokogiri-1.6.6.3/mkmf.log 
"gcc -o conftest -I/Users/jon/.rvm/rubies/ruby-2.2.2/include/ruby-2.2.0/x86_64-darwin14 ... 
-lruby.2.2.0 -lpthread -lgmp -ldl -lobjc " 
ld: library not found for -lgmp 
clang: error: linker command failed with exit code 1 (use -v to see invocation) 
checked program was: 
/* begin */ 
1: #include "ruby.h" 
2: 
3: int main(int argc, char **argv) 
4: { 
5: return 0; 
6: } 
/* end */ 

Answer 1

FIX

xcode-select --install 

Ponownie uruchomiono gem install rails.