Error running all specs in rspec

Whenever I'm trying to run rspec for whole project (there are over 1000 tests) after finishing all testcases I receive following error:

/home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:183:in `formatted_backtrace': undefined method `backtrace' for nil:NilClass (NoMethodError)
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:191:in `colorized_formatted_backtrace'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:276:in `formatted_message_and_backtrace'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:199:in `fully_formatted'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:122:in `block in fully_formatted_pending_examples'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:121:in `each'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:121:in `each_with_index'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/notifications.rb:121:in `fully_formatted_pending_examples'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/formatters/base_text_formatter.rb:50:in `dump_pending'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/reporter.rb:146:in `block in notify'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/reporter.rb:145:in `each'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/reporter.rb:145:in `notify'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/reporter.rb:123:in `finish'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/reporter.rb:64:in `report'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/runner.rb:108:in `run_specs'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/runner.rb:86:in `run'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/runner.rb:70:in `run'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/lib/rspec/core/runner.rb:38:in `invoke'
from /home/borisano/.rbenv/versions/2.1.5/lib/ruby/gems/2.1.0/gems/rspec-core-3.2.2/exe/rspec:4:in `<top (required)>'
from /home/borisano/.rbenv/versions/2.1.5/bin/rspec:23:in `load'
from /home/borisano/.rbenv/versions/2.1.5/bin/rspec:23:in `<main>'

When I run only limited number of test cases, say, one file or single folder, everything works fine.

Any ideas on how to fix that?