My Rails application works fine on my machine through localhost, but when I deployed it to Heroku, I got this list of errors:
2012-11-11T04:59:20+00:00 heroku[web.1]: Starting process with command `bundle exec thin start -R config.ru -e production -p 38941`
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/builders/c.rb:114:in `shared_object'
2012-11-11T04:59:33+00:00 app[web.1]: /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/compilers/gcc.rb:29:in `compile': compile error: see logs at /tmp/.ffi-inline-18803/85aad7364f11885370e58c4391df70e29ef22bbe.log (CompilationError)
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/builders.rb:87:in `instance_eval'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/builders.rb:87:in `build'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/inline.rb:39:in `inline'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/inline.rb:54:in `singleton_inline'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/tesseract-ocr-0.1.5/lib/tesseract/c.rb:34:in `<module:C>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/tesseract-ocr-0.1.5/lib/tesseract/c.rb:31:in `<module:Tesseract>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/tesseract-ocr-0.1.5/lib/tesseract/c.rb:29:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `block in require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:236:in `load_dependency'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/tesseract-ocr-0.1.5/lib/tesseract/api.rb:26:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/ffi-inline-0.0.4/lib/ffi/inline/builders.rb:90:in `block in build'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/tesseract-ocr-0.1.5/lib/tesseract-ocr.rb:35:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:68:in `block (2 levels) in require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:66:in `each'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `block in require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:236:in `load_dependency'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:68:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:55:in `each'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:55:in `require'
2012-11-11T04:59:33+
00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler.rb:128:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/config/application.rb:7:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/config/environment.rb:2:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/bundler-1.2.1/lib/bundler/runtime.rb:66:in `block in require'
2012-11-11T04:59:33+00:00 app[web.1]: from config.ru:3:in `require'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/config/environment.rb:2:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from config.ru:3:in `block in <main>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/controllers/controller.rb:181:in `load_rackup_config'
2012-11-11T04:59:33+00:00 app[web.1]: from config.ru:1:in `new'
2012-11-11T04:59:33+00:00 app[web.1]: from config.ru:1:in `<main>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/bin/thin:6:in `<top (required)>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/bin/thin:19:in `load'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/bin/thin:19:in `<main>'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/rack/adapter/loader.rb:33:in `eval'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/rack/adapter/loader.rb:33:in `load'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/controllers/controller.rb:71:in `start'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/runner.rb:185:in `run_command'
2012-11-11T04:59:33+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/runner.rb:151:in `run!'
2012-11-11T04:59:34+00:00 heroku[web.1]: Process exited with status 1
2012-11-11T04:59:38+00:00 heroku[router]: Error H10 (App crashed)
I cannot depict the heads or tails of this, except that Heroku may have problems with the Ruby Tesseract gem I am using. Maybe the problem is addiction?
UPDATE:
After some further searching, it turns out that the problem is with the Tesseract gem .
According to the support ticket, I need to establish these paths ...
ENV['CFLAGS'] = '-I/path/to/the/headers'
ENV['LDFLAGS'] = '-L/path/to/the/libs'
... but I don’t know how to install them or what are the paths to the headers / libraries actually in the Rails application deployed to Heroku. Any ideas?