catch segmentation fault and show wrong lines in source code

cdebug.sh

#!/bin/bash
# usage: cdebug.sh ./a.out
# (remember to add "-rdynamic" and "-g" option to gcc!)
# example: gcc -O0 -g -rdynamic foo.c && cdebug.sh ./a.out

if test "$#" -lt 1; then
	echo "usage: cdebug.sh ./a.out"
	echo "(remember to add '-rdynamic' and '-g' option to gcc!)"
	echo "example: gcc -O0 -g -rdynamic foo.c && cdebug.sh ./a.out"
	exit 1
fi

# set filename
EXECFILE=$1

# RANGE value for sed 'p'
RANGE=2

# set env and exec
export LD_PRELOAD=/usr/lib/libSegFault.so
export SEGFAULT_USE_ALTSTACK=1
export SEGFAULT_SIGNALS=all

ADDR=`eval $EXECFILE 2>&1 | grep "${EXECFILE}.*\[.*\]" | egrep -o "\[0x[0-9a-z]+\]" | head -1 | tr -d "]["`
echo segfault at $EXECFILE $ADDR

# find wrong line in source code
SRCFILE=`addr2line -e $EXECFILE $ADDR | cut -d: -f1`
LINE=`addr2line -e $EXECFILE $ADDR | cut -d: -f2`
MAXLINE=`wc -l $SRCFILE | cut -d" " -f1`
#echo line: $LINE

# show error code
FROM=`expr $LINE - $RANGE`
TO=`expr $LINE + $RANGE`

if test $FROM -lt 1; then
	FROM=1
fi

if test $TO -gt $MAXLINE; then
	TO=$MAXLINE
fi

#echo from: $FROM to: $TO maxline: $MAXLINE
echo $SRCFILE:$LINE
nl -ba $SRCFILE |  sed -n "${FROM},${TO}p"