On Tue, Jul 16, 2019 at 12:24 AM Martin Samuelsson <ratpoi...@gyvetre.netizen.se> wrote: > Interesting... Would you be able to run that reproducable seg. fault though > gdb and generate a stack trace of the crash?
Never used gdb before, but I believe I have produced a stack trace below. I might be reading this wrong, but it seems like add_to_window_list (frame #0) is called with the rp_screen *s argument set to null. This would explain why it segfaults at the first s-> member access. As a newbie I get a little confused by frame #1. Despite scanwins having one argument and all call sites provide an argument, gdb does not list any arguments for the frame. If this simply means that s=null, then I'm not sure exactly why a segfault is not produced when s->root is accessed when calling XQueryTree or XGetWindowAttributes. Perhaps you can shed some light on that, or at least give me a pointer for what information I need to provide next. Thanks for taking your time! ======================================================================== root@2f988de7c2d8:~/ratpoison# gdb ./src/ratpoison GNU gdb (Debian 8.2.1-2) 8.2.1 Copyright (C) 2018 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>. Find the GDB manual and other documentation resources online at: <http://www.gnu.org/software/gdb/documentation/>. For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from ./src/ratpoison...done. (gdb) run Starting program: /root/ratpoison/src/ratpoison warning: Error disabling address space randomization: Operation not permitted [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. add_to_window_list (s=0x0, w=4194305) at window.c:181 181 new_window->colormap = DefaultColormap (dpy, s->screen_num); (gdb) info stack #0 add_to_window_list (s=0x0, w=4194305) at window.c:181 #1 0x0000561e59326249 in scanwins () at manage.c:452 #2 0x0000561e5931218a in main (argc=1, argv=0x7ffdcb6af288) at main.c:432 (gdb) info frame Stack level 0, frame at 0x7ffdcb6af070: rip = 0x561e5932a0ab in add_to_window_list (window.c:181); saved rip = 0x561e59326249 called by frame at 0x7ffdcb6af150 source language c. Arglist at 0x7ffdcb6af028, args: s=0x0, w=4194305 Locals at 0x7ffdcb6af028, Previous frame's sp is 0x7ffdcb6af070 Saved registers: rbx at 0x7ffdcb6af050, rbp at 0x7ffdcb6af058, r12 at 0x7ffdcb6af060, rip at 0x7ffdcb6af068 (gdb) info args s = 0x0 w = 4194305 (gdb) up #1 0x0000561e59326249 in scanwins () at manage.c:452 452 win = add_to_window_list (screen, wins[i]); (gdb) info frame Stack level 1, frame at 0x7ffdcb6af150: rip = 0x561e59326249 in scanwins (manage.c:452); saved rip = 0x561e5931218a called by frame at 0x7ffdcb6af1b0, caller of frame at 0x7ffdcb6af070 source language c. Arglist at 0x7ffdcb6af068, args: Locals at 0x7ffdcb6af068, Previous frame's sp is 0x7ffdcb6af150 Saved registers: rbx at 0x7ffdcb6af128, rbp at 0x7ffdcb6af130, r12 at 0x7ffdcb6af138, r13 at 0x7ffdcb6af140, rip at 0x7ffdcb6af148 (gdb) info args No arguments. (gdb) up #2 0x0000561e5931218a in main (argc=1, argv=0x7ffdcb6af288) at main.c:432 432 scanwins (); (gdb) info frame Stack level 2, frame at 0x7ffdcb6af1b0: rip = 0x561e5931218a in main (main.c:432); saved rip = 0x7fe58c6dd09b caller of frame at 0x7ffdcb6af150 source language c. Arglist at 0x7ffdcb6af148, args: argc=1, argv=0x7ffdcb6af288 Locals at 0x7ffdcb6af148, Previous frame's sp is 0x7ffdcb6af1b0 Saved registers: rbx at 0x7ffdcb6af178, rbp at 0x7ffdcb6af180, r12 at 0x7ffdcb6af188, r13 at 0x7ffdcb6af190, r14 at 0x7ffdcb6af198, r15 at 0x7ffdcb6af1a0, rip at 0x7ffdcb6af1a8 (gdb) info args argc = 1 argv = 0x7ffdcb6af288 (gdb) up Initial frame selected; you cannot go up. (gdb) _______________________________________________ Ratpoison-devel mailing list Ratpoison-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/ratpoison-devel
