Run issue

[tomas-cerny]

I have the version from git and does not work, please help

gems/commander-4.4.3/lib/commander/runner.rb:409:in block in require_program': program version required (Commander::Runner::CommandError)
from /Users/xx/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/commander-4.4.3/lib/commander/runner.rb:408:in each' from /Users/xx/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/commander-4.4.3/lib/commander/runner.rb:408:in require_program'
from /Users/xx/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/commander-4.4.3/lib/commander/runner.rb:52:in run!' from /Users/xx/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/commander-4.4.3/lib/commander/delegates.rb:15:in run!'
from /Users/xx/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/commander-4.4.3/lib/commander/import.rb:5:in block in <top (required)>' /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract/references/score.rb:11:in module:Score': uninitialized constant Libsvm::Model (NameError)
Did you mean? Module
from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract/references/score.rb:4:in <module:PdfExtract>' from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract/references/score.rb:3:in <top (required)>'
from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract/references/references.rb:3:in require_relative' from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract/references/references.rb:3:in <top (required)>'
from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract.rb:10:in require_relative' from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf/extract.rb:10:in <top (required)>'
from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf-extract.rb:1:in require_relative' from /Users/xx/Downloads/extractor/pdfextract-master/lib/pdf-extract.rb:1:in <top (required)>'
from ../pdfextract-master/bin/pdf-extract:5:in require_relative' from ../pdfextract-master/bin/pdf-extract:5:in

'
`

When I do > sudo gem install pdf-extract

I fail on
error: unknown warning option '-Werror=unused-command-line-argument-hard-error-in-future'; did you mean '-Werror=unused-command-line-argument'? [-Werror,-Wunknown-warning-option]

Undefined symbols for architecture x86_64:
"_iconv", referenced from:
_main in conftest-5b1568.o
"_iconv_open", referenced from:
_main in conftest-5b1568.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)