#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:44
  [Error: pthread_kill.c was not found in source tree]
#1  __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
  [Error: pthread_kill.c was not found in source tree]
#2  __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
  [Error: pthread_kill.c was not found in source tree]
#3  0x00007f5a1b83c406 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
  [Error: raise.c was not found in source tree]
#4  0x00007f5a1b82287c in __GI_abort () at ./stdlib/abort.c:79
  [Error: abort.c was not found in source tree]
#5  0x00007f5a1b82279b in __assert_fail_base (fmt=0x7f5a1b9b9f68 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x5581de61c013 "false", file=file@entry=0x5581de61c004 "../src/picom.c", line=line@entry=425, function=function@entry=0x5581de61de00 <__PRETTY_FUNCTION__.24> "destroy_backend") at ./assert/assert.c:92
  [Error: assert.c was not found in source tree]
#6  0x00007f5a1b833b86 in __assert_fail (assertion=assertion@entry=0x5581de61c013 "false", file=file@entry=0x5581de61c004 "../src/picom.c", line=line@entry=425, function=function@entry=0x5581de61de00 <__PRETTY_FUNCTION__.24> "destroy_backend") at ./assert/assert.c:101
  [Error: assert.c was not found in source tree]
#7  0x00005581de5db57e in destroy_backend (ps=ps@entry=0x5581df645d00) at ../src/picom.c:425
  420: 			if (win_check_flags_any(w, WIN_FLAGS_IMAGES_STALE) &&
  421: 			    w->state == WSTATE_MAPPED) {
  422: 				log_warn("Stale flags set for mapped window %#010x "
  423: 				         "during backend destruction",
  424: 				         w->base.id);
  425: 				assert(false);
  426: 			}
  427: 			// Unmapped windows can still have stale flags set, because their
  428: 			// stale flags aren't handled until they are mapped.
  429: 			win_clear_flags(w, WIN_FLAGS_IMAGES_STALE);
  430: 			win_release_images(ps->backend_data, w);
#8  0x00005581de5de497 in configure_root (ps=0x5581df645d00) at ../src/picom.c:602
  597: 		}
  598: 
  599: 		if (!has_root_change) {
  600: 			// deinit/reinit backend and free up resources if the backend
  601: 			// cannot handle root change
  602: 			destroy_backend(ps);
  603: 		}
  604: 		free_paint(ps, &ps->tgt_buffer);
  605: 	}
  606: 
  607: 	ps->root_width = r->width;
#9  handle_root_flags (ps=0x5581df645d00) at ../src/picom.c:665
  660: 		}
  661: 		ps->root_flags &= ~(uint64_t)ROOT_FLAGS_SCREEN_CHANGE;
  662: 	}
  663: 
  664: 	if ((ps->root_flags & ROOT_FLAGS_CONFIGURED) != 0) {
  665: 		configure_root(ps);
  666: 		ps->root_flags &= ~(uint64_t)ROOT_FLAGS_CONFIGURED;
  667: 	}
  668: }
  669: 
  670: static struct managed_win *
#10 handle_pending_updates (loop=<optimized out>, ps=0x5581df645d00) at ../src/picom.c:1430
  1425: 
  1426: 		// Handle screen changes
  1427: 		// This HAS TO be called before refresh_windows, as handle_root_flags
  1428: 		// could call configure_root, which will release images and mark them
  1429: 		// stale.
  1430: 		handle_root_flags(ps);
  1431: 
  1432: 		// Process window flags (window mapping)
  1433: 		refresh_windows(ps);
  1434: 
  1435: 		{
#11 0x00005581de5e141c in draw_callback_impl (revents=<optimized out>, ps=0x5581df645d00, loop=0x7f5a1bf52720 <default_loop_struct>) at ../src/picom.c:1460
  1455: 		log_debug("Exited critical section");
  1456: 	}
  1457: }
  1458: 
  1459: static void draw_callback_impl(EV_P_ session_t *ps, int revents attr_unused) {
  1460: 	handle_pending_updates(EV_A_ ps);
  1461: 
  1462: 	if (ps->first_frame) {
  1463: 		// If we are still rendering the first frame, if some of the windows are
  1464: 		// unmapped/destroyed during the above handle_pending_updates() call, they
  1465: 		// won't have pixmap before we rendered it, causing us to crash.
#12 draw_callback (loop=0x7f5a1bf52720 <default_loop_struct>, w=0x5581df645d90, revents=<optimized out>) at ../src/picom.c:1550
  1545: }
  1546: 
  1547: static void draw_callback(EV_P_ ev_idle *w, int revents) {
  1548: 	session_t *ps = session_ptr(w, draw_idle);
  1549: 
  1550: 	draw_callback_impl(EV_A_ ps, revents);
  1551: 
  1552: 	// Don't do painting non-stop unless we are in benchmark mode, or if
  1553: 	// draw_callback_impl thinks we should continue painting.
  1554: 	if (!ps->o.benchmark && !ps->redraw_needed) {
  1555: 		ev_idle_stop(EV_A_ & ps->draw_idle);
#13 0x00007f5a1bf46773 in ev_invoke_pending (loop=0x7f5a1bf52720 <default_loop_struct>) at ev.c:3770
  [Error: ev.c was not found in source tree]
#14 0x00007f5a1bf4a041 in ev_run (flags=0, loop=0x7f5a1bf52720 <default_loop_struct>) at ev.c:4190
  [Error: ev.c was not found in source tree]
#15 ev_run (loop=0x7f5a1bf52720 <default_loop_struct>, flags=flags@entry=0) at ev.c:4021
  [Error: ev.c was not found in source tree]
#16 0x00005581de5d9d3d in session_run (ps=<optimized out>) at ../src/picom.c:2465
  2460: 		ev_idle_start(ps->loop, &ps->draw_idle);
  2461: 	} else {
  2462: 		// Let's draw our first frame!
  2463: 		queue_redraw(ps);
  2464: 	}
  2465: 	ev_run(ps->loop, 0);
  2466: }
  2467: 
  2468: /**
  2469:  * The function that everybody knows.
  2470:  */
#17 main (argc=<optimized out>, argv=<optimized out>) at ../src/picom.c:2567
  2562: 			write(pfds[1], &tmp, sizeof tmp);
  2563: 			close(pfds[1]);
  2564: 			// We only do this once
  2565: 			need_fork = false;
  2566: 		}
  2567: 		session_run(ps_g);
  2568: 		quit = ps_g->quit;
  2569: 		if (quit && ps_g->o.write_pid_path) {
  2570: 			pid_file = strdup(ps_g->o.write_pid_path);
  2571: 		}
  2572: 		session_destroy(ps_g);