Installing old Rails 2.4 (well, somebody need to maintain that legacy code…) on Ubuntu with Ruby 2.4.10 You can get failure during Nokogirii installation. Log ends with:
compiling xslt_stylesheet.c
xslt_stylesheet.c:112:13: warning: ‘swallow_superfluous_xml_errors’ defined but not used [-Wunused-function]
112 | static void swallow_superfluous_xml_errors(void * userdata, xmlErrorPtr error, …)
| ^~~~~~~~~~
cc1: warning: unrecognized command line option ‘-Wno-self-assign’
cc1: warning: unrecognized command line option ‘-Wno-constant-logical-operand’
cc1: warning: unrecognized command line option ‘-Wno-parentheses-equality’
linking shared-object nokogiri/nokogiri.so
Cleaning files only used during build.
rm -rf /home/viciu/.rvm/gems/ruby-2.4.10@rails42/gems/nokogiri-1.10.10/ext/nokogiri/tmp/x86_64-pc-linux-gnu/ports
rm -rf /home/viciu/.rvm/gems/ruby-2.4.10@rails42/gems/nokogiri-1.10.10/ports
current directory: /home/viciu/.rvm/gems/ruby-2.4.10@rails42/gems/nokogiri-1.10.10/ext/nokogiri
make "DESTDIR=" install
make: /usr/bin/mkdir: Command not found
make: *** [Makefile:200: .sitearchdir.-.nokogiri.time] Error 127
make install failed, exit code 2
Simplest fix is to link mkdir in place where make expects to find it (on Ubuntu make is in /bin not /usr/bin):
sudo ln -s /bin/mkdir /usr/bin/mkdir
After that You will could install gem and bundle install will work.