Install mysql2 gem on macOS Sierra : <p>I'm trying to install mysql2 gem (0.4.5) on macOS Sierra (10.12.1) and getting the error. I don't have local mysql server, it's remote. </p>

<p>Here is error log:</p>

<pre><code>checking for ruby/thread.h... yes
checking for rb_thread_call_without_gvl() in ruby/thread.h... yes
checking for rb_thread_blocking_region()... no
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes 
checking for rb_intern3()... yes 
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Using mysql_config at /usr/local/bin/mysql_config
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checking for mysql.h... yes
checking for errmsg.h... yes
checking for mysqld_error.h... yes
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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-connector-c/6.1.9/lib
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creating Makefile

To see why this extension failed to compile, please check the mkmf.log   which can be found here:
    /Users/user/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/extensions/x86_64-darwin-16/2.3.0-static/mysql2-0.4.4/mkmf.log

current directory: /Users/user/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/mysql2-0.4.4/ext/mysql2
make "DESTDIR=" clean

current directory: /Users/user/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/mysql2-0.4.4/ext/mysql2
make "DESTDIR="
compiling client.c
compiling infile.c
compiling mysql2_ext.c
compiling result.c
compiling statement.c
linking shared-object mysql2/mysql2.bundle
ld: library not found for -l-lpthread
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [mysql2.bundle] Error 1

make failed, exit code 2
</code></pre>

<p>Did anyone meet similar error? </p>
