New comment by richfelker on void-packages repository

https://github.com/void-linux/void-packages/issues/31722#issuecomment-880916714

Comment:
The backtrace needs libc debug info to be more meaningful. It's almost surely a UAF bug or buffer overflow or other memory corruption by the caller, but seeing exactly *where* in `free` it crashed would help tell you which type of bug to look for.