远程设备是一个arm路由器。运行程序报Segmentation fault。首先使用-g选项重新编译，然后开始gdb调试：

1 远程运行gdbserver

$ gdbserver :1234 /usr/bin/netmand

中间的COMM参数可以是一个tty设备。也可以是host:port，表示监听tcp连接。

2 本地执行交叉编译版本的gdb

$ /opt/toolchain-ipq4018/bin/arm-unknown-linux-gnueabihf-gdb usr/bin/netmand

GNU gdb (crosstool-NG 1.24.0) 8.2.1
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-build_pc-linux-gnu --target=arm-unknown-linux-gnueabihf".
Type "show configuration" for configuration details.

For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
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For help, type "help".
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Reading symbols from usr/bin/netmand...done.
(gdb) set solib-search-path .
(gdb) target remote 192.168.0.2:1234
Remote debugging using 192.168.0.2:1234
Reading symbols from /opt/toolchain-ipq4018/arm-unknown-linux-gnueabihf/sysroot/lib/ld-linux-armhf.so.3...done.
0xb6fcea00 in _start () from /opt/toolchain-ipq4018/arm-unknown-linux-gnueabihf/sysroot/lib/ld-linux-armhf.so.3
(gdb) b main
Breakpoint 1 at 0x11500: file netman.c, line 83.
(gdb) c
Continuing.

Breakpoint 1, main (argc=1, argv=0xbefffea4) at netman.c:83
83              if (fd_init(&netman_ctx) < 0) {
(gdb) info sharedlibrary
From        To          Syms Read   Shared Object Library
0xb6fcea00 0xb6fe9e04 Yes         /opt/toolchain-ipq4018/arm-unknown-linux-gnueabihf/sysroot/lib/ld-linux-armhf.so.3
0xb6fbb914 0xb6fbc72c Yes         /work/xrouter/output/ipq4018/rootfs/usr/lib/liblog.so
0xb6fa87e8 0xb6fa914c Yes         /work/xrouter/output/ipq4018/rootfs/usr/lib/libcommon.so
0xb6f93a88 0xb6f96050 Yes         /work/xrouter/output/ipq4018/rootfs/usr/lib/libconfig.so
0xb6e6a140 0xb6f5eb30 Yes         /opt/toolchain-ipq4018/arm-unknown-linux-gnueabihf/sysroot/lib/libc.so.6
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x00012018 in setup_proto (proto=0x26000) at proto.c:154
154             if (proto->is_bridge)
(gdb) bt
#0 0x00012018 in setup_proto (proto=0x26000) at proto.c:154
#1 0x0001144c in apply_proto (ctx=0x250ac <netman_ctx>) at netman.c:56
#2 0x000115b8 in main (argc=1, argv=0xbefffea4) at netman.c:100
(gdb) l proto.c:154
149     int setup_proto(struct proto *proto)
150     {
151             int ret;
152             int i;
153
154             if (proto->is_bridge)
155             {
156                     ret = add_br(proto->l2if);
157                     if (ret < 0) {
158                             plog(NETMAN, ERR, "create bridge %s failed: %d (%s)",

用到了相关的命令：

调用的时候带了文件路径：/opt/toolchain-ipq4018/bin/arm-unknown-linux-gnueabihf-gdb usr/bin/netmand，如果没有带，直接执行gdb，则可以使用file命令加载。

set solib-search-path .

设置共享库的搜索路径，由于是远程调试，不设置的话，会直接使用/usr/lib/liblog.so等，显然会找不到，使用set sysroot . 设置系统根目录也是可以的。

target remote 192.168.0.2:1234

连接到远程target

info sharedlibrary

显示共享库

显示调用栈

list proto.c:154

显示出错的源代码

Note：测试发现远程使用非调试版本，源码不变，本地编译为-g版本，也是可以的。

参考：

https://sourceware.org/gdb/current/onlinedocs/gdb/Files.html

ILD

1 远程运行gdbserver

2 本地执行交叉编译版本的gdb