Although it is probably not useful, here is one the exception traces
I got (when compiling with "ec -loop" without -verbose and without
inlining) after the re-finalize.  Top of the stack looks like:

-------------------------------------------------------------------------------
FEATURE_SERVER      item @6                                             
<000000000E873404>  (From COMPILER_SERVER) Feature call on void target.  Fail
-------------------------------------------------------------------------------

In this case, there is a call on Void target.  Another time I got
a seg fault with a completely different trace.  Full trace attached.