Estou tentando instalar um aplicativo de software livre rails 3.2.21 que usa omysql2 gem, mas quando eu tento executar obundle commant, recebo o seguinte erro:

Fetching: mysql2-0.3.18.gem (100%)
Building native extensions.  This could take a while...
p
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

    /Users/my_username/.rvm/rubies/ruby-2.1.2/bin/ruby -r ./siteconf20150614-72129-orqsb7.rb extconf.rb
checking for ruby/thread.h... yes
checking for rb_thread_call_without_gvl() in ruby/thread.h... yes
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes
checking for rb_intern3()... yes
-----
Using mysql_config at /usr/local/bin/mysql_config
-----
checking for mysql.h... yes
checking for errmsg.h... yes
checking for mysqld_error.h... yes
-----
Don't know how to set rpath on your system, if MySQL libraries are not in path mysql2 may not load
-----
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Setting libpath to /usr/local/Cellar/mysql/5.6.25/lib
-----
creating Makefile

make "DESTDIR=" clean

make "DESTDIR="
compiling client.c
compiling infile.c
compiling mysql2_ext.c
compiling result.c
linking shared-object mysql2/mysql2.bundle
ld: warning: directory not found for option '-L/Users/travis/.sm/pkg/active/lib'
ld: library not found for -lssl
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [mysql2.bundle] Error 1

make failed, exit code 2

Gem files will remain installed in /Users/my_username/.rvm/rubies/ruby-2.1.2/lib/ruby/gems/2.1.0/gems/mysql2-0.3.18 for inspection.
Results logged to /Users/my_username/.rvm/rubies/ruby-2.1.2/lib/ruby/gems/2.1.0/extensions/x86

Eu tentei desinstalar todas as versões domysql Eu instalei via homebrew e os reinstalei, da seguinte maneira:

brew uninstall --force mysql && brew install mysql

Em seguida, executando:

sudo gem install mysql2

Conforme sugerido por várias perguntas semelhantes feitas aqui, mas ainda resulta no mesmo erro acima.

Alguém poderia oferecer orientações sobre como colocar isso em funcionamento?