title: Can't install mysql gem on OS X
body: <p>I'm doing a </p>
  
  <blockquote>
    <p>sudo gem install mysql</p>
  </blockquote>
  
  <p>on OS X to install the mysql gem. This fails with the following output:</p>
  
  <blockquote>
    <p>Building native extensions.  This could take a while...</p>
    
    <p>ERROR:  Error installing mysql:</p>
    
    <p>ERROR: Failed to build gem native extension.</p>
    
    <p>/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby extconf.rb</p>
    
    <p>checking for mysql_ssl_set()... yes</p>
    
    <p>checking for rb_str_set_len()... yes</p>
    
    <p>checking for rb_thread_start_timer()... no</p>
    
    <p>checking for mysql.h... yes</p>
    
    <p>creating Makefile</p>
    
    <p>make "DESTDIR=" clean</p>
    
    <p>make "DESTDIR="</p>
    
    <p>compiling mysql.c</p>
    
    <p>linking shared-object mysql/mysql_api.bundle</p>
    
    <p>clang: error: unknown argument: '-multiply_definedsuppress' [-Wunused-command-line-> argument-hard-error-in-future]</p>
    
    <p>clang: note: this will be a hard error (cannot be downgraded to a warning) in the future</p>
    
    <p>make: <em>*</em> [mysql_api.bundle] Error 1</p>
    
    <p>make failed, exit code 2</p>
    
    <p>Gem files will remain installed in /Library/Ruby/Gems/2.0.0/gems/mysql-2.9.1 for inspection.</p>
    
    <p>Results logged to /Library/Ruby/Gems/2.0.0/extensions/universal-darwin-13/2.0.0/mysql-2.9.1/gem_make.out</p>
  </blockquote>
  
  <p>Any idea what could be causing this? I have mysql installed with homebrew if that makes a difference.</p>