sudo gem update

Updating installed gems
Updating libxml-ruby
Building native extensions. This could take a while...
ERROR: Error installing libxml-ruby:
ERROR: Failed to build gem native extension.

current directory: /Library/Ruby/Gems/2.6.0/gems/libxml-ruby-3.2.0/ext/libxml
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -I /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0 -r ./siteconf20200625-91131-1va8p4j.rb extconf.rb
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby: warning: shebang line ending with \r may cause problems
checking for libxml/xmlversion.h in /opt/include/libxml2,/opt/local/include/libxml2,/usr/local/include/libxml2,/usr/include/libxml2,/usr/local/include... no
checking for xmlParseDoc() in -lxml2... yes
*** 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
--without-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=/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/$(RUBY_BASE_NAME)
--with-xml2-config
--without-xml2-config
--with-xml2-dir
--without-xml2-dir
--with-xml2-include
--without-xml2-include=${xml2-dir}/include
--with-xml2-lib
--without-xml2-lib=${xml2-dir}/lib
--with-xml2lib
--without-xml2lib
extconf failure: Cannot find libxml2.

Install the library or try one of the following options to extconf.rb:

--with-xml2-config=/path/to/xml2-config
--with-xml2-dir=/path/to/libxml2
--with-xml2-lib=/path/to/libxml2/lib
--with-xml2-include=/path/to/libxml2/include


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

/Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/libxml-ruby-3.2.0/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /Library/Ruby/Gems/2.6.0/gems/libxml-ruby-3.2.0 for inspection.
Results logged to /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/libxml-ruby-3.2.0/gem_make.out
Updating openssl
Building native extensions. This could take a while...
ERROR: Error installing openssl:
ERROR: Failed to build gem native extension.

Gem files will remain installed in /Library/Ruby/Gems/2.6.0/gems/openssl-2.2.0 for inspection.
Results logged to /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/openssl-2.2.0/gem_make.out
Gems updated: libxml-ruby openssl

current directory: /Library/Ruby/Gems/2.6.0/gems/openssl-2.2.0/ext/openssl
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -I /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0 -r ./siteconf20200625-91208-1cznbua.rb extconf.rb
checking for t_open() in -lnsl... no
checking for socket() in -lsocket... no
checking for openssl/ssl.h... no
*** 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
--without-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=/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/$(RUBY_BASE_NAME)
--with-openssl-dir
--with-openssl-include
--without-openssl-include=${openssl-dir}/include
--with-openssl-lib
--without-openssl-lib=${openssl-dir}/lib
--with-kerberos-dir
--without-kerberos-dir
--with-kerberos-include
--without-kerberos-include=${kerberos-dir}/include
--with-kerberos-lib
--without-kerberos-lib=${kerberos-dir}/lib
--with-debug
--without-debug
--enable-debug
--disable-debug
--with-nsllib
--without-nsllib
--with-socketlib
--without-socketlib
--with-openssl-config
--without-openssl-config
--with-pkg-config
--without-pkg-config
extconf.rb:99:in `

': OpenSSL library could not be found. You might want to use --with-openssl-dir= option to specify the prefix where OpenSSL is installed. (RuntimeError)

export PATH="/usr/local/opt/ruby/bin:$PATH"

Updating openssl
Fetching openssl-2.2.0.gem
Building native extensions. This could take a while...
Successfully installed openssl-2.2.0
Parsing documentation for openssl-2.2.0
Installing ri documentation for openssl-2.2.0
Installing darkfish documentation for openssl-2.2.0
Done installing documentation for openssl after 4 seconds
Parsing documentation for openssl-2.2.0
Done installing documentation for openssl after 0 seconds