Rails6で画像編集ができるRMagickを導入する

gem 'rmagick'

Building native extensions. This could take a while...
ERROR:  Error installing rmagick:
        ERROR: Failed to build gem native extension.

    current directory: /home/ec2-user/.rvm/gems/ruby-2.6.5/gems/rmagick-4.2.2/ext/RMagick
/home/ec2-user/.rvm/rubies/ruby-2.6.5/bin/ruby -I /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/site_ruby/2.6.0 -r ./siteconf20210806-10706-10mubyf.rb extconf.rb
checking for brew... no
checking for pacman... no
checking for Ruby version >= 2.3.0... yes
checking for pkg-config... yes
checking for outdated ImageMagick version (<= 6.7.7)... no
checking for gcc... yes
checking for __GNUC__... *** 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=/home/ec2-user/.rvm/rubies/ruby-2.6.5/bin/$(RUBY_BASE_NAME)
/home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:467:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:585:in `block in try_compile'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:534:in `with_werror'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:585:in `try_compile'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:852:in `macro_defined?'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:994:in `block in have_macro'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:959:in `block in checking_for'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:361:in `block (2 levels) in postpone'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:331:in `open'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:361:in `block in postpone'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:331:in `open'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:357:in `postpone'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:958:in `checking_for'
        from /home/ec2-user/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/mkmf.rb:993:in `have_macro'
        from extconf.rb:99:in `configure_compile_options'
        from extconf.rb:19:in `initialize'
        from extconf.rb:398:in `new'
        from extconf.rb:398:in `<main>'

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

  /home/ec2-user/.rvm/gems/ruby-2.6.5/extensions/x86_64-linux/2.6.0/rmagick-4.2.2/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /home/ec2-user/.rvm/gems/ruby-2.6.5/gems/rmagick-4.2.2 for inspection.
Results logged to /home/ec2-user/.rvm/gems/ruby-2.6.5/extensions/x86_64-linux/2.6.0/rmagick-4.2.2/gem_make.out

"gcc -o conftest -I/home/ec2-user/.rvm/rubies/ruby-2.6.5/include/ruby-2.6.0/x86_64-linux -I/home/ec2-user/.rvm/rubies/ruby-2.6.5/include/ruby-2.6.0/ruby/backward -I/home/ec2-user/.rvm/rubies/ruby-2.6.5/include/ruby-2.6.0 -I.  -fopenmp -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16 -I/usr/include/ImageMagick-6    -fopenmp -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16 -I/usr/include/ImageMagick-6   conftest.c  -L. -L/home/ec2-user/.rvm/rubies/ruby-2.6.5/lib -Wl,-rpath,/home/ec2-user/.rvm/rubies/ruby-2.6.5/lib  -lMagickCore-6.Q16      -lMagickCore-6.Q16    -Wl,-rpath,'/../lib' -Wl,-rpath,'/../lib' -lruby  -lm   -lc"
gcc: error: libgomp.spec: No such file or directory
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main(int argc, char **argv)
4: {
5:   return 0;
6: }
/* end */