Here is the backtrace from my original report. `self-priv = NULL` causes the segmentation fault. Has that been addressed in more recent versions?

	Core was generated by `simple-scan'.
	Program terminated with signal 11, Segmentation fault.
	#0  page_view_page_size_changed_cb (p=<optimized out>, self=0x265a430) at page-view.c:4089
	4089		self->priv->update_image = TRUE;
	(gdb) l
	4084	
	4085	
	4086	static void page_view_page_size_changed_cb (PageView* self, Page* p) {
	4087		g_return_if_fail (self != NULL);
	4088		g_return_if_fail (p != NULL);
	→ 4089		self->priv->update_image = TRUE;
	4090		g_signal_emit_by_name (self, "size-changed");
	4091		g_signal_emit_by_name (self, "changed");
	4092	}
	4093
	(gdb) bt f
	#0  page_view_page_size_changed_cb (p=<optimized out>, self=0x265a430) at page-view.c:4089
	No locals.
	#1  _page_view_page_size_changed_cb_page_size_changed (_sender=<optimized out>, self=0x265a430) at page-view.c:224
	No locals.
	#2  0x00007ffb85d766e0 in g_closure_invoke (closure=0x2622200, return_value=0x0, n_param_values=1, param_values=0x7fff47dbab00, 
	    invocation_hint=0x7fff47dbaaa0) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gclosure.c:777
		marshal = 0x40d470 <g_cclosure_marshal_VOID__VOID@plt>
		marshal_data = 0x0
		in_marshal = 0
		real_closure = 0x26221e0
		__PRETTY_FUNCTION__ = "g_closure_invoke"
	#3  0x00007ffb85d87750 in signal_emit_unlocked_R (node=node@entry=0x23c6760, detail=detail@entry=0, instance=instance@entry=0x265a4c0, 
	    emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fff47dbab00)
	    at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3551
		tmp = <optimized out>
		handler = 0x222be70
		accumulator = 0x0
		emission = {next = 0x7fff47dbb0b0, instance = 0x265a4c0, ihint = {signal_id = 243, detail = 0, run_type = G_SIGNAL_RUN_FIRST}, 
		  state = EMISSION_RUN, chain_type = 4}
		class_closure = 0x0
		hlist = 0x2658d00
		handler_list = 0x2658d00
		return_accu = 0x0
		accu = {g_type = 0, data = {{v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, 
		      v_double = 0, v_pointer = 0x0}, {v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, 
		      v_double = 0, v_pointer = 0x0}}}
		signal_id = 243
		max_sequential_handler_number = 4079
		return_value_altered = 1
	#4  0x00007ffb85d8f6bc in g_signal_emit_valist (instance=instance@entry=0x265a4c0, signal_id=signal_id@entry=243, detail=detail@entry=0, 
	    var_args=var_args@entry=0x7fff47dbad98) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3300
		instance_and_params = 0x7fff47dbab00
		signal_return_type = 4
		param_values = 0x7fff47dbab18
		node = 0x23c6760
		i = <optimized out>
		n_params = 0
		__PRETTY_FUNCTION__ = "g_signal_emit_valist"
	#5  0x00007ffb85d8fd60 in g_signal_emit_by_name (instance=instance@entry=0x265a4c0, 
	    detailed_signal=detailed_signal@entry=0x42e94a "size-changed") at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3393
		var_args = {{gp_offset = 16, fp_offset = 48, overflow_arg_area = 0x7fff47dbaed0, reg_save_area = 0x7fff47dbade0}}
		detail = 0
		signal_id = 243
		__PRETTY_FUNCTION__ = "g_signal_emit_by_name"
	#6  0x0000000000413ef8 in page_set_page_info (self=self@entry=0x265a4c0, info=info@entry=0x24d7240) at page.c:410
		_tmp0_ = 0x24d7240
		_tmp1_ = <optimized out>
		_tmp2_ = 0x24d7240
		_tmp3_ = <optimized out>
		_tmp4_ = 0x24d7240
		_tmp5_ = <optimized out>
		_tmp6_ = 0x24d7240
		_tmp7_ = <optimized out>
		_tmp8_ = <optimized out>
		_tmp11_ = <optimized out>
		_tmp13_ = <optimized out>
		_tmp14_ = <optimized out>
		_tmp15_ = <optimized out>
		_tmp16_ = <optimized out>
		_tmp17_ = <optimized out>
		_tmp18_ = <optimized out>
		_tmp19_ = 8606250
		_tmp20_ = <optimized out>
		_tmp20__length1 = <optimized out>
		_tmp21_ = <optimized out>
		__PRETTY_FUNCTION__ = "page_set_page_info"
	#7  0x000000000041a4e7 in application_scanner_page_info_cb (info=<optimized out>, scanner=<optimized out>, self=<optimized out>)
	    at simple-scan.c:1154
		_tmp1_ = <optimized out>
		_tmp4_ = 0x24d7240
		_tmp7_ = 0x24d7240
		_tmp11_ = <optimized out>
		_tmp5_ = <optimized out>
		_tmp2_ = 0x24d7240
		page = 0x265a4c0
		_tmp8_ = <optimized out>
		_tmp3_ = <optimized out>
		_tmp6_ = 0x265a4c0
		_tmp9_ = <optimized out>
		_tmp10_ = 0x0
		_tmp0_ = 0x24d7240
	#8  _application_scanner_page_info_cb_scanner_got_page_info (_sender=<optimized out>, info=0x24d7240, self=<optimized out>)
	    at simple-scan.c:459
	No locals.
	#9  0x00007ffb85d766e0 in g_closure_invoke (closure=0x23ccb60, return_value=0x0, n_param_values=2, param_values=0x7fff47dbb120, 
	    invocation_hint=0x7fff47dbb0c0) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gclosure.c:777
		marshal = 0x41e980 <g_cclosure_user_marshal_VOID__SCAN_PAGE_INFO>
		marshal_data = 0x0
		in_marshal = 0
		real_closure = 0x23ccb40
		__PRETTY_FUNCTION__ = "g_closure_invoke"
	#10 0x00007ffb85d87750 in signal_emit_unlocked_R (node=node@entry=0x23cb5c0, detail=detail@entry=0, instance=instance@entry=0x237b3e0, 
	    emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fff47dbb120)
	    at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3551
		tmp = <optimized out>
		handler = 0x23cb160
		accumulator = 0x0
		emission = {next = 0x0, instance = 0x237b3e0, ihint = {signal_id = 252, detail = 0, run_type = G_SIGNAL_RUN_FIRST}, 
		  state = EMISSION_RUN, chain_type = 4}
		class_closure = 0x0
		hlist = 0x23cb160
		handler_list = 0x23cb160
		return_accu = 0x0
		accu = {g_type = 0, data = {{v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, 
		      v_double = 0, v_pointer = 0x0}, {v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, 
		      v_double = 0, v_pointer = 0x0}}}
		signal_id = 252
		max_sequential_handler_number = 4079
		return_value_altered = 0
	#11 0x00007ffb85d8f6bc in g_signal_emit_valist (instance=instance@entry=0x237b3e0, signal_id=signal_id@entry=252, detail=detail@entry=0, 
	    var_args=var_args@entry=0x7fff47dbb3c8) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3300
		instance_and_params = 0x7fff47dbb120
		signal_return_type = 4
		param_values = 0x7fff47dbb138
		node = 0x23cb5c0
		i = <optimized out>
		n_params = 1
		__PRETTY_FUNCTION__ = "g_signal_emit_valist"
	#12 0x00007ffb85d8fd60 in g_signal_emit_by_name (instance=0x237b3e0, detailed_signal=0x43049e "got-page-info")
	    at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./gobject/gsignal.c:3393
		var_args = {{gp_offset = 24, fp_offset = 48, overflow_arg_area = 0x7fff47dbb500, reg_save_area = 0x7fff47dbb410}}
		detail = 0
		signal_id = 252
		__PRETTY_FUNCTION__ = "g_signal_emit_by_name"
	#13 0x0000000000421b51 in scanner_notify_idle_cb (self=0x237b3e0) at scanner.c:3108
		_tmp1_ = 0x2709d20
		_tmp0_ = <optimized out>
		notification = 0x2709d20
	#14 _scanner_notify_idle_cb_gsource_func (self=0x237b3e0) at scanner.c:3122
	No locals.
	#15 0x00007ffb85ab7355 in g_main_dispatch (context=0x2219b90) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./glib/gmain.c:2539
		dispatch = 0x7ffb85ab5070 <g_idle_dispatch>
		was_in_call = 0
		user_data = 0x237b3e0
		callback = 0x421b20 <_scanner_notify_idle_cb_gsource_func>
		cb_funcs = 0x7ffb85d639c0
		cb_data = 0x7ffb78692e00
		current_source_link = {data = 0x7ffb7826bd90, next = 0x0}
		need_destroy = <optimized out>
		source = 0x7ffb7826bd90
		current = 0x23e43c0
		i = <optimized out>
	#16 g_main_context_dispatch (context=context@entry=0x2219b90) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./glib/gmain.c:3075
	No locals.
	#17 0x00007ffb85ab7688 in g_main_context_iterate (context=0x2219b90, block=block@entry=1, dispatch=dispatch@entry=1, 
	    self=<error reading variable: Unhandled dwarf expression opcode 0xfa>) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./glib/gmain.c:3146
		max_priority = 2147483647
		timeout = 144
		some_ready = 1
		nfds = <optimized out>
		allocated_nfds = <optimized out>
		fds = 0x26ec740
	#18 0x00007ffb85ab7a82 in g_main_loop_run (loop=0x2468770) at /tmp/buildd/glib2.0-2.33.12+really2.32.4/./glib/gmain.c:3340
		__PRETTY_FUNCTION__ = "g_main_loop_run"
	#19 0x00007ffb870433b5 in gtk_main () at /tmp/buildd/gtk+3.0-3.4.2/./gtk/gtkmain.c:1161
		loop = 0x2468770
	#20 0x000000000041c6b5 in application_main (args=0x7fff47dbb748, args_length1=1) at simple-scan.c:2440
		result = 0
		_tmp0_ = <optimized out>
		_tmp1_ = 0x2218570
		c = 0x2218570
		_tmp2_ = 0x2218570
		_tmp3_ = 0x2218570
		_tmp4_ = <optimized out>
		_tmp14_ = <optimized out>
		_tmp16_ = <optimized out>
		device = 0x0
		_tmp29_ = <optimized out>
		_tmp29__length1 = <optimized out>
		_tmp39_ = <optimized out>
		_tmp40_ = <optimized out>
		_tmp41_ = <optimized out>
		path = 0x22188c0 "/home/paul/.cache/simple-scan/simple-scan.log"
		_tmp42_ = <optimized out>
		_tmp43_ = <optimized out>
		_tmp44_ = 0x22188c0 "/home/paul/.cache/simple-scan/simple-scan.log"
		_tmp45_ = 0x22188c0 "/home/paul/.cache/simple-scan/simple-scan.log"
		_tmp46_ = <optimized out>
		_tmp47_ = <optimized out>
		_tmp48_ = 0x0
		_tmp49_ = 0x21f6000
		app = 0x21f6000
		_tmp50_ = 0x21f6000
		_inner_error_ = 0x0
	#21 0x00007ffb84bfaead in __libc_start_main (main=<optimized out>, argc=<optimized out>, ubp_av=<optimized out>, init=<optimized out>, 
	    fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff47dbb738) at libc-start.c:228
		result = <optimized out>
		unwind_buf = {cancel_jmp_buf = {{jmp_buf = {0, -1426006794154566420, 4250432, 140734398969664, 0, 0, 1426306099471949036, 
		        1423919368694111468}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x42db60, 0x7fff47dbb748}, data = {prev = 0x0, 
		      cleanup = 0x0, canceltype = 4381536}}}
		not_first_call = <optimized out>
	#22 0x000000000040db69 in _start ()
	(gdb) p* self
	$1 = {parent_instance = {g_class = 0x22590e0}, ref_count = 1, priv = 0x0}