Error description Thrown by the Factor VM when a Unix signal is received. While signal numbers are system-specific, the following are relatively standard:
4 - Illegal instruction. If you see this error, it is a bug in Factor's compiler and should be reported.
8 - Arithmetic exception. Most likely a divide by zero in /i.
10, 11 - Memory protection fault. This error suggests invalid values are being passed to C functions by an alien-invoke. Factor also uses memory protection to trap stack underflows and overflows, but usually these are reported as their own errors. Sometimes they'll show up as a generic signal 11, though.
The Windows equivalent of a signal 11 is a SEH fault. When one occurs, the runtime throws a signal error, even though it does not correspond to a Unix signal.