I don't have fully reproducible test case yet, but this crash in GC occured when I tried in Monodevelop 5.11 (was got from master branch) to open Monodevelop solution file and then click (Version Control/Show Log and do some scroll). I did not notice such error on previous version of mono (4.0)
OS: Ubuntu Linux 12.04 32 bit
Mono JIT compiler version 4.2.1 (Stable 126.96.36.199/6dd2d0d Thu Nov 12 09:53:18 UTC 2015)
*** glibc detected *** /usr/bin/mono: double free or corruption (fasttop): 0x8f858dd8 ***
/* see attachment for crash details */
Created attachment 13881 [details]
This is really strange, because the GC doesn't use malloc.
Could you install debug symbol for mono and attach a crash with symbol information?
The current one has no actionable information due to all symbols having being stripped.
We have not received the requested information. If you are still experiencing this issue please provide all the requested information and reopen the bug report.