title: Installing gtk2 gem on ruby
body: <p>Im currently running debian 10 operating system. I try to install gtk2 gem for ruby but I have the following error. I updated gcc and libtool but I got the same error. I have already installed ruby-dev, and updated all the gem but I'm stuck with this error</p>
  <pre><code>gem install gtk2
  Building native extensions. This could take a while...
  ERROR:  Error installing gtk2:
      ERROR: Failed to build gem native extension.
  
      current directory: /var/lib/gems/2.7.0/gems/gobject-introspection-3.4.3/ext/gobject-introspection
  /usr/bin/ruby2.7 -I /usr/local/lib/site_ruby/2.7.0 -r ./siteconf20201218-8651-102gp3h.rb extconf.rb
  checking for --enable-debug-build option... no
  checking for -Wall option to compiler... yes
  checking for -Waggregate-return option to compiler... yes
  checking for -Wcast-align option to compiler... yes
  checking for -Wextra option to compiler... yes
  checking for -Wformat=2 option to compiler... yes
  checking for -Winit-self option to compiler... yes
  checking for -Wlarger-than-65500 option to compiler... yes
  checking for -Wmissing-declarations option to compiler... yes
  checking for -Wmissing-format-attribute option to compiler... yes
  checking for -Wmissing-include-dirs option to compiler... yes
  checking for -Wmissing-noreturn option to compiler... yes
  checking for -Wmissing-prototypes option to compiler... yes
  checking for -Wnested-externs option to compiler... no
  checking for -Wold-style-definition option to compiler... yes
  checking for -Wpacked option to compiler... yes
  checking for -Wp,-D_FORTIFY_SOURCE=2 option to compiler... yes
  checking for -Wpointer-arith option to compiler... yes
  checking for -Wundef option to compiler... yes
  checking for -Wout-of-line-declaration option to compiler... no
  checking for -Wunsafe-loop-optimizations option to compiler... yes
  checking for -Wwrite-strings option to compiler... yes
  checking for Homebrew... no
  checking for gobject-introspection-1.0... 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=/usr/bin/$(RUBY_BASE_NAME)2.7
      --enable-debug-build
      --disable-debug-build
      --with-pkg-config
      --without-pkg-config
      --with-override-variables
      --without-override-variables
  
  To see why this extension failed to compile, please check the mkmf.log which can be found here:
  
    /var/lib/gems/2.7.0/extensions/x86_64-linux/2.7.0/gobject-introspection-3.4.3/mkmf.log
  
  extconf failed, exit code 1
  
  Gem files will remain installed in /var/lib/gems/2.7.0/gems/gobject-introspection-3.4.3 for inspection.
  Results logged to /var/lib/gems/2.7.0/extensions/x86_64-linux/2.7.0/gobject-introspection-3.4.3/gem_make.out
   
  </code></pre>
  <p>I can run ruby on xubuntu 20.04 without problem.</p>