/usr/src/gcc-4.8/debian/acats-killer.sh is in gcc-4.8-source 4.8.5-4ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62  | #! /bin/sh
# on ia64 systems, the acats hangs in unaligned memory accesses.
# kill these testcases.
pidfile=acats-killer.pid
usage()
{
    echo >&2 "usage: `basename $0` [-p <pidfile>] <ada logfile> <next logfile>"
    exit 1
}
while [ $# -gt 0 ]; do
    case $1 in
    -p)
	pidfile=$2
	shift
	shift
	;;
    -*)
	usage
	;;
    *)
	break
    esac
done
[ $# -eq 2 ] || usage
logfile=$1
stopfile=$2
interval=30
echo $$ > $pidfile
while true; do
    if [ -f "$stopfile" ]; then
	echo "`basename $0`: finished."
	rm -f $pidfile
	exit 0
    fi
    sleep $interval
    if [ ! -f "$logfile" ]; then
	continue
    fi
    pids=$(ps aux | awk '/testsuite\/ada\/acats\/tests/ { print $2 }')
    if [ -n "$pids" ]; then
	sleep $interval
        pids2=$(ps aux | awk '/testsuite\/ada\/acats\/tests/ { print $2 }')
	if [ "$pids" = "$pids2" ]; then
	    #echo kill: $pids
	    kill $pids
	    sleep 1
            pids2=$(ps aux | awk '/testsuite\/ada\/acats\/tests/ { print $2 }')
	    if [ "$pids" = "$pids2" ]; then
	        #echo kill -9: $pids
	        kill -9 $pids
	    fi
	fi
    fi
done
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