bt of sigfpe_ip in gdb:
#0  0x0000000000400a4a in sighandler(int) ()
#1  <signal handler called>
#2  0x0000000000400a10 in fpe() ()
#3  0x0000000000400a9a in main ()


--- Executing ---
*** Running with gcc's unwind ***
caught...
*** Running with libunwind's unwind ***
terminate called after throwing an instance of 'int'
./sigfpe.sh: line 18:  6135 Aborted                 LD_PRELOAD=/usr/lib/libunwind.so ./sigfpe

--- Printing ip and before flag ---
*** Running with gcc's unwind ***
ip: 0x400a76, ip-before-ins: 0
ip: 0x400a10, ip-before-ins: 1
*** Running with libunwind's unwind ***
ip: 0x400a76, ip-before-ins: 0
ip: 0x400a10, ip-before-ins: 0