Issue #9757 has been updated by David Faber. Sorry I missed the notification about your message. I've retried this with trunk (ruby 2.2.0dev (2014-04-25 trunk 45720) [x86_64-darwin13]) and it just gives a SystemStackError, with message "stack level too deep" now, so it does seem like stack overflow. Does that indicate that the segfault is fixed in trunk, and there may be a different bug in RSpec causing the stack overflow in the first place? ---------------------------------------- Bug #9757: Segfault in 2.1.1 from RSpec expect_any_instance_of https://bugs.ruby-lang.org/issues/9757#change-46319 * Author: David Faber * Status: Feedback * Priority: Normal * Assignee: * Category: core * Target version: * ruby -v: ruby 2.1.1p76 (2014-02-24 revision 45161) [x86_64-darwin13.0] * Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN ---------------------------------------- The following spec causes a segfault for me in ruby 2.1.1 on OS X 10.9.2: ~~~ class A def a 'a' end end class B def b 'b' end end describe 'segfault' do it 'should make unused recorders' do expect_any_instance_of(A).to receive(:a) expect_any_instance_of(B).to receive(:b) end it 'should crash ruby' do A.new.a B.new.b end end ~~~ Some more info: ~~~ $ ruby -v ruby 2.1.1p76 (2014-02-24 revision 45161) [x86_64-darwin13.0] $ bundle exec gem list *** LOCAL GEMS *** bundler (1.6.0.rc) diff-lcs (1.2.5) rspec (3.0.0.beta2) rspec-core (3.0.0.beta2) rspec-expectations (3.0.0.beta2) rspec-mocks (3.0.0.beta2) rspec-support (3.0.0.beta2) ~~~ I've also attached the crash report generated by OS X. Let me know if you need some more info. Sorry if this is a duplicate, I found some similar looking reports (#9309, #9461, #9315), but I don't really know enough to recognize if they are exactly the same issue. ---Files-------------------------------- ruby-crash.log (58 KB) -- https://bugs.ruby-lang.org/