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#!/usr/bin/perl -T
#
# This code is used by lib/perl5db.t !!!
#
use Scalar::Util qw(tainted);

# [perl #76872] don't taint $DB::sub

sub f {}

BEGIN {
    print "[\$^X]" if tainted($^X);
    ($^X || 1)  && f(); # maybe taint $DB::sub;
    print "[\$DB::sub]" if tainted($DB::sub);
}
print "[done]";