I inserted the following code in the listener:

USING: io.encodings.utf8 fry grouping ;

"resource:basis/alarms/alarms.factor" utf8 file-contents
[ length >array [ 1+ ] map ] keep
'[ _ swap clump [ " " join ] map ] map


factor silently crashes. 
although it uses alot of memory (~400MB on my system), it doesn't run out of it, I still have hundreds more MB when it crashes.