Error message about exception in upcall not visible when using custom System.err

[Maurizio Cimadamore]

Hi,
if the exception was propagated normally to the Java caller, and left 
uncaught, I believe the JVM would terminate by printing the exception 
stack trace on the standard error. If the standard error is redirected, 
you won't see such trace, even in the event of a non-FFM exceptional exit.

So, I'm not sure there is anything special for FFM to do here. If we 
wanted exceptional exit to be "more noisy" (e.g. so that it prints stack 
traces and/or other messages in more than just System.err) that would 
have to be a JDK-wide thing, and not merely an FFM change.

In other words, if System.err is redirected, then:

> you might not see this message and are wondering why the JVM has just 
> exited without any details and without JVM crash report.

is always a possibility, FFM or not.

Cheers
Maurizio