I grabbed 2.0.7 to see if it was fixed here and it appears to be. Apologies if I was re-reporting an existing bug that was both known about and fixed.
- bug#14035: Bug Report: scm_with_guile inside pthread segfaul... johnanthony
- bug#14035: Fixed in 2.0.7 johnanthony
- bug#14035: Fixed in 2.0.7 Mark H Weaver