on windows does not make any change. 
C:\Perl\bin>set PERL_SIGNALS=unsafe
C:\Perl\bin>perl -e"$SIG{ALRM} = sub{die}; alarm(1); $re = ('a*' x80).
+'(b|c)'; $str = 'a' x 80;$str =~ /$re/;"

[download]
does not finish.
     s;;Just-me-not-h-Ni-m-P-Ni-lm-I-ar-O-Ni;;tr?IerONim-?HAcker ?d;print

In reply to Re^4: Timeout alarm for regex by Ieronim
in thread Timeout alarm for regex by Otogi

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