It means that during execution of the trap handler another trap has occurred,
and that several times.
In some cases, this is an error because of overflow of some internal tables.
-.IP "no RETURN from procedure function"
+.IP "no RETURN from function procedure"
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-This error occurs when a procedure function does not return properly
+This error occurs when a function procedure does not return properly
("falls" through).
.IP "illegal instruction"
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