Hello, I'm starting work on an ARM Cortex-A5 platform. I've setup a cross-build environment on Centos 6, my toolchain is gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux since my build system is 32-bits (I don't have 64-bit hardware/OS available). I've written a simple hello_world and managed to compile on my build environment and execute in the target system. However, I can't debug the application.
#include <stdio.h>
int main(int argc, char **argv) { printf("Hello world! (hola mundo) [v2]\n"); return 0; } [toradex@EL-Toradex Hello_world]$ ~/gcc-linaro/bin/arm-linux-gnueabihf-gcc -g -o Hello_world main.c
I've already confirmed that the program to debug runs OK, I've connected via SSH and run it, it just prints a hello message as expected.
When I try to debug, I get a SIGSEGV and then the following reports: If I use the provided gdbinit in gcc-linaro/share/gdb/gdbinit, I get the following error:
---------------------------------------------------------------------- /home/toradex/gcc-linaro/share/gdb/gdbinit:6: Error in sourced command file: Python scripting is not supported in this copy of GDB. ----------------------------------------------------------------------
If I don't, then gdb complains it can't locate source files:
---------------------------------------------------------------------- Can't find a source file at "/cbuild/slaves/oorts/crosstool-ng/builds/arm-linux-gnueabihf-linux/.build/src/eglibc-linaro-2.19-2014.08/elf/dl-fini.c" Locate the file or edit the source lookup path to include its location. ----------------------------------------------------------------------
The SIGSEGV occurs before main(), I can't do anything on startup:
---------------------------------------------------------------------- TARGET: ------ root@colibri-vf:~# gdbserver :2345 /home/root/Hello_world BUILD: ----- [toradex@EL-Toradex ~]$ gcc-linaro/bin/arm-linux-gnueabihf-gdb workspace/Hello_world/Debug/Hello_world GNU gdb (crosstool-NG linaro-1.13.1-4.9-2014.09 - Linaro GCC 4.9-2014.09) 7.6.1-2013.10 Copyright (C) 2013 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 "--host=i686-build_pc-linux-gnu --target=arm-linux-gnueabihf". For bug reporting instructions, please see: https://bugs.launchpad.net/gcc-linaro... Reading symbols from /media/sf_EL-Toradex/Hello_world/Debug/Hello_world...done. (gdb) target remote 192.168.1.6:2345 Remote debugging using 192.168.1.6:2345 Reading symbols from /home/toradex/gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux/arm-linux-gnueabihf/libc/lib/ld-linux-armhf.so.3...done. Loaded symbols for /home/toradex/gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux/arm-linux-gnueabihf/libc/lib/ld-linux-armhf.so.3 process_dl_debug (dl_debug=0x0, dl_debug@entry=<error reading variable: Cannot access memory at address 0x34>) at rtld.c:2415 2415 rtld.c: No such file or directory. (gdb) continue Continuing.
Program received signal SIGSEGV, Segmentation fault. 0x76fe36f8 in _dl_sort_fini (maps=0x7efff98c, nmaps=0, used=0x0, ns=<optimized out>) at dl-fini.c:70 70 dl-fini.c: No such file or directory. (gdb) ----------------------------------------------------------------------
I do need some help here. Following is what I know how to get out of /proc/mypid/ Thanks.
----------------------------------------------------------------------
AT "ERROR READING VARIABLE"
root@colibri-vf:~# cat /proc/438/maps 00010000-00011000 r-xp 00000000 00:0d 15533 /home/root/Hello_world 00020000-00021000 rw-p 00000000 00:0d 15533 /home/root/Hello_world 76fd8000-76ff7000 r-xp 00000000 00:0d 15010 /lib/ld-2.19-2014.04.so 76ffd000-76ffe000 r-xp 00000000 00:00 0 [sigpage] 76ffe000-77000000 rw-p 0001e000 00:0d 15010 /lib/ld-2.19-2014.04.so 7efdf000-7f000000 rw-p 00000000 00:00 0 [stack] ffff0000-ffff1000 r-xp 00000000 00:00 0 [vectors] root@colibri-vf:~# cat /proc/438/stack [<8002b2c4>] ptrace_stop+0x11c/0x214 [<8002c3b8>] get_signal+0x2c8/0x534 [<80011088>] do_signal+0x1a0/0x3ec [<80011468>] do_work_pending+0x90/0xd0 [<8000e5e0>] work_pending+0xc/0x20 [<ffffffff>] 0xffffffff root@colibri-vf:~# cat /proc/438/stat 438 (Hello_world) t 435 438 412 34816 438 1073741824 33 0 0 0 0 0 0 0 20 0 1 0 171447 286720 20 4294967295 65536 66668 2130705728 2130705728 1996328256 0 0 268435456 0 2147660484 0 0 17 0 0 0 0 0 0 132204 132488 135168 2130705997 2130706020 2130706020 2130706405 0 root@colibri-vf:~# cat /proc/438/status Name: Hello_world State: t (tracing stop) Tgid: 438 Ngid: 0 Pid: 438 PPid: 435 TracerPid: 435 Uid: 0 0 0 0 Gid: 0 0 0 0 FDSize: 32 Groups: 0 VmPeak: 304 kB VmSize: 280 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 80 kB VmRSS: 80 kB VmData: 4 kB VmStk: 136 kB VmExe: 4 kB VmLib: 124 kB VmPTE: 6 kB VmSwap: 0 kB Threads: 1 SigQ: 0/819 SigPnd: 0000000000000000 ShdPnd: 0000000000000000 SigBlk: 0000000000000000 SigIgn: 0000000010000000 SigCgt: 0000000000000000 CapInh: 0000000000000000 CapPrm: 0000003fffffffff CapEff: 0000003fffffffff CapBnd: 0000003fffffffff Cpus_allowed: 1 Cpus_allowed_list: 0 voluntary_ctxt_switches: 1 nonvoluntary_ctxt_switches: 0 root@colibri-vf:~# cat /proc/438/syscall 0 0x0 0x0 0x0 0x0 0x0 0x0 0x7efffd40 0x76fd8d40 root@colibri-vf:~#
AFTER "CONTINUE", WHEN "SIGSEGV" --------------------------------
root@colibri-vf:~# cat /proc/438/maps 00010000-00011000 r-xp 00000000 00:0d 15533 /home/root/Hello_world 00020000-00021000 rw-p 00000000 00:0d 15533 /home/root/Hello_world 76ea1000-76fca000 r-xp 00000000 00:0d 15031 /lib/libc-2.19-2014.04.so 76fca000-76fd2000 ---p 00129000 00:0d 15031 /lib/libc-2.19-2014.04.so 76fd2000-76fd5000 rw-p 00129000 00:0d 15031 /lib/libc-2.19-2014.04.so 76fd5000-76fd8000 rw-p 00000000 00:00 0 76fd8000-76ff7000 r-xp 00000000 00:0d 15010 /lib/ld-2.19-2014.04.so 76ff7000-76ff8000 rw-p 00000000 00:00 0 76ff8000-76ffc000 r--p 00000000 00:0d 14058 /etc/ld.so.cache 76ffc000-76ffd000 rw-p 00000000 00:00 0 76ffd000-76ffe000 r-xp 00000000 00:00 0 [sigpage] 76ffe000-77000000 rw-p 0001e000 00:0d 15010 /lib/ld-2.19-2014.04.so 7efdf000-7f000000 rw-p 00000000 00:00 0 ffff0000-ffff1000 r-xp 00000000 00:00 0 [vectors] root@colibri-vf:~# cat /proc/438/stack [<8002b2c4>] ptrace_stop+0x11c/0x214 [<8002c3b8>] get_signal+0x2c8/0x534 [<80011088>] do_signal+0x1a0/0x3ec [<80011468>] do_work_pending+0x90/0xd0 [<8000e5e0>] work_pending+0xc/0x20 [<ffffffff>] 0xffffffff root@colibri-vf:~# cat /proc/438/stat 438 (Hello_world) t 435 438 412 34816 438 1073741824 49 0 0 0 0 0 0 0 20 0 1 0 171447 1585152 74 4294967295 65536 66668 2130705728 0 1996371704 0 0 268435456 0 2147660484 0 0 17 0 0 0 0 0 0 132204 132488 135168 2130705997 2130706020 2130706020 2130706405 0 root@colibri-vf:~# cat /proc/438/status Name: Hello_world State: t (tracing stop) Tgid: 438 Ngid: 0 Pid: 438 PPid: 435 TracerPid: 435 Uid: 0 0 0 0 Gid: 0 0 0 0 FDSize: 32 Groups: 0 VmPeak: 1548 kB VmSize: 1548 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 296 kB VmRSS: 296 kB VmData: 24 kB VmStk: 136 kB VmExe: 4 kB VmLib: 1312 kB VmPTE: 6 kB VmSwap: 0 kB Threads: 1 SigQ: 0/819 SigPnd: 0000000000000000 ShdPnd: 0000000000000000 SigBlk: 0000000000000000 SigIgn: 0000000010000000 SigCgt: 0000000000000000 CapInh: 0000000000000000 CapPrm: 0000003fffffffff CapEff: 0000003fffffffff CapBnd: 0000003fffffffff Cpus_allowed: 1 Cpus_allowed_list: 0 voluntary_ctxt_switches: 2 nonvoluntary_ctxt_switches: 1 root@colibri-vf:~# cat /proc/438/syscall 0 0xffffffff 0x1934 0x76ffed90 0x76ea1000 0x0 0x0 0x0 0x76fe36f8 root@colibri-vf:~#