Bug #15360
Updated by brockspratlen (Brock Spratlen) over 5 years ago
I think I've discovered a Ruby bug, possibly introduced in 2.5. I've attached a reproduction script; running it on Ruby 2.5.0+ (including previews of 2.6.0) seems to always produce a flood of printed `ThreadError: deadlock; recursive locking` exceptions, even though the reproduction code doesn't appear to do any recursive locking. Running the same script on Ruby 2.4.5 doesn't produce any `ThreadError: deadlock; recursive locking` exceptions. I've run the script several times on Ruby 2.4.5, I simply can't reproduce the raising of `ThreadError: deadlock; recursive locking` with this script on 2.4.5. Curiously, removing the `puts e.class` on line 24 25 causes the bug to go away: `ThreadError: deadlock; recursive locking` never gets raised regardless of which Ruby version I'm running. Given this oddity, I can't help but think the issue is something around writing to stdout. This change in particular looks suspect: https://bugs.ruby-lang.org/issues/9323 Thank you! Brock