The program indeed segfaults, below is the GDB backtrace. The segfault happens when the program tries to access the attribute format_widget, which is a null pointer; with a breakpoint before the segfault, printing the attribute returns 0x0:
(gdb) print gphoto->format_widget $3 = (gphoto_widget *) 0x0
#0 0x0001f87c in gphoto_open (shutter_release_port=0x0) at /home/pi/Packages/indi-gphoto/indi-gphoto/indi-gphoto/gphoto_driver.cpp:935 #1 0x00017880 in GPhotoCCD::Connect (this=0x36230) at /home/pi/Packages/indi-gphoto/indi-gphoto/indi-gphoto/gphoto_ccd.cpp:575 #2 0x76eedc3c in INDI::DefaultDevice::ISNewSwitch (this=this@entry=0x36230, dev=dev@entry=0x361d8 "GPhoto CCD", name=name@entry=0x41c60 "CONNECTION", states=states@entry=0x41e28, names=names@entry=0x41e38, n=1, n@entry=107192) at /home/pi/Packages/libindi/libindi/libindi/libs/indibase/defaultdevice.cpp:215 #3 0x76efae58 in INDI::CCD::ISNewSwitch (this=this@entry=0x36230, dev=dev@entry=0x361d8 "GPhoto CCD", name=name@entry=0x41c60 "CONNECTION", states=states@entry=0x41e28, names=names@entry=0x41e38, n=1, n@entry=100864) at /home/pi/Packages/libindi/libindi/libindi/libs/indibase/indiccd.cpp:1520 #4 0x0001a2b8 in GPhotoCCD::ISNewSwitch (this=0x36230, dev=0x361d8 "GPhoto CCD", name=0x41c60 "CONNECTION", states=0x41e28, names=0x41e38, n=1) at /home/pi/Packages/indi-gphoto/indi-gphoto/indi-gphoto/gphoto_ccd.cpp:515 #5 0x00018a00 in ISNewSwitch (dev=0x361d8 "GPhoto CCD", name=0x41c60 "CONNECTION", states=0x41e28, names=0x41e38, num=num@entry=1) at /home/pi/Packages/indi-gphoto/indi-gphoto/indi-gphoto/gphoto_ccd.cpp:94 #6 0x76ee514c in dispatch (root=0x360a0, msg=msg@entry=0x7effeed4 "") at /home/pi/Packages/libindi/libindi/libindi/indidriver.c:1005 #7 0x76ee5794 in clientMsgCB (fd=<optimized out>, arg=<optimized out>) at /home/pi/Packages/libindi/libindi/libindi/indidriver.c:855 #8 0x76ee89a8 in callCallback (rfdp=0x7efff314) at /home/pi/Packages/libindi/libindi/libindi/eventloop.c:346 #9 oneLoop () at /home/pi/Packages/libindi/libindi/libindi/eventloop.c:432 #10 0x76ee8b7c in eventLoop () at /home/pi/Packages/libindi/libindi/libindi/eventloop.c:105 #11 0x76eded28 in main (ac=0, av=<optimized out>) at /home/pi/Packages/libindi/libindi/libindi/indidrivermain.c:97 #12 0x7692d294 in __libc_start_main (main=0x7efff544, argc=1990533120, argv=0x7692d294 <__libc_start_main+276>, init=<optimized out>, fini=0x227e8 <__libc_csu_fini>, rtld_fini=0x76fdf408 <_dl_fini>, stack_end=0x7efff544) at libc-start.c:287 #13 0x00015d44 in _start ()