[docker-user@api-es-log-aggregator-1 ~]$ sudo /usr/sbin/td-agent-gem install gssapi
Building native extensions.  This could take a while...
ERROR:  Error installing gssapi:
        ERROR: Failed to build gem native extension.

    current directory: /opt/td-agent/embedded/lib/ruby/gems/2.4.0/gems/ffi-1.9.25/ext/ffi_c
/opt/td-agent/embedded/bin/ruby -r ./siteconf20180606-32047-uefddj.rb extconf.rb
checking for ffi.h... *** 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.

Provided configuration options:
        --with-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=/opt/td-agent/embedded/bin/$(RUBY_BASE_NAME)
        --with-ffi_c-dir
        --without-ffi_c-dir
        --with-ffi_c-include
        --without-ffi_c-include=${ffi_c-dir}/include
        --with-ffi_c-lib
        --without-ffi_c-lib=${ffi_c-dir}/lib
        --with-libffi-config
        --without-libffi-config
        --with-pkg-config
        --without-pkg-config
/opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:468:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:599:in `try_cpp'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:1106:in `block in have_header'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:956:in `block in checking_for'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:351:in `block (2 levels) in postpone'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:321:in `open'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:351:in `block in postpone'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:321:in `open'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:347:in `postpone'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:955:in `checking_for'
        from /opt/td-agent/embedded/lib/ruby/2.4.0/mkmf.rb:1105:in `have_header'
        from extconf.rb:16:in `<main>'

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /opt/td-agent/embedded/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0/ffi-1.9.25/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /opt/td-agent/embedded/lib/ruby/gems/2.4.0/gems/ffi-1.9.25 for inspection.
Results logged to /opt/td-agent/embedded/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0/ffi-1.9.25/gem_make.out