代码调试篇:gdb调试快速入门指南

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代码调试篇(1):gdb调试快速入门指南

Author:StormQ

Monday, 25. February 2019 10:31PM


启动 gdb


启动一个不带参数的进程

命令:

# executable-file 为可执行文件的路径
$ gdb <executable-file>

示例:

# 启动一个不带参数的可执行程序 main,位于./samples目录下
$ gdb ./samples/main

返回上一级


启动一个带参数的进程

命令:

# executable-file 为可执行文件的路径
# arg1 为可执行文件的第一个参数
# argn 为可执行文件的第n个参数
$ gdb --args <executable-file> <arg1> <argn>

示例:

# 启动一个带参数的可执行程序 main,位于./samples目录下
# 假设程序参数只有一个,为配置文件 ./config.txt
$ gdb --args ./samples/main ./config.txt

返回上一级


调试一个正在运行的进程

命令:

$ gdb
# process-id为要调试进程的进程ID
(gdb) attach <process-id>

示例:

$ gdb
# 假设要调试进程的进程ID为8888
(gdb) attach 8888

返回上一级


使用命令文件调试进程

命令:

# command-file为存放gdb命令的文件
# 为了便于区分,该文件使用.gdb结尾(当然也可以使用其他格式结尾,比如:.txt)
$ gdb -x <command-file>

示例:

$ gdb -x main.gdb

假设 main.gdb 文件的内容为:

# 指定可执行文件的路径
file ./samples/main
# 设置可执行文件的参数(如果有的话)
set args ./config.txt
# 启动进程
start
# 继续执行
c

返回上一级


调试进程


查看进程信息

  • 查看进程ID、可执行文件路径、当前目录

命令:

# info命名可缩写为i
(gdb) info proc

示例:

(gdb) i proc 
process 11356
cmdline = '/home/tmp/b_Og'
cwd = '/home/tmp'
exe = '/home/tmp/b_Og'

从输出结果中可以看出,进程ID为 11356,进程启动项为 /home/tmp/b_Og,当前目录(即启动gdb时所在的目录)为 /home/tmp,可执行程序为 /home/tmp/b_Og。

  • 查看所有线程

命令:

(gdb) i threads

示例:

(gdb) i threads 
  Id   Target Id         Frame 
* 1    Thread 0x7ffff7fce740 (LWP 1549) "main" 0x00007ffff7626c1d in nanosleep ()
    at ../sysdeps/unix/syscall-template.S:84
  2    Thread 0x7ffff6f42700 (LWP 1553) "main" 0x00007ffff7626c1d in nanosleep ()
    at ../sysdeps/unix/syscall-template.S:84

打印结果中Id列左侧带*的为当前线程,ID列为 gdb 自定义的线程ID,Target Id为真实的线程ID(这里有两个线程,线程ID分别为:1549、1553),Frame为线程的当前帧(包含:线程运行到什么位置了等信息)。

  • 查看断点当前所在的线程

命令:

(gdb) p $_thread

示例:

(gdb) p $_thread
$1 = 1

注意: 打印结果所显示的线程ID(这里是1)是 gdb 内部自定义的(即i threads命令输出结果中最左侧的Id列的值),而不是真实的线程ID。

返回上一级


查看堆栈信息

  • 查看当前线程的堆栈信息

命令:

# 只打印堆栈信息的调用层次
(gdb) bt
# 打印堆栈信息的调用层次,并打印函数参数和局部变量的值
(gdb) bt full

示例:

(gdb) bt
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004010ad in main () at main.cpp:11
(gdb) bt full
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
No locals.
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
        __s = __r = 0
        __ns = __r = 10000000
        __ts = tv_sec = 0, tv_nsec = 7543688
#2  0x00000000004010ad in main () at main.cpp:11
No locals.
  • 查看所有线程的堆栈信息

命令:

# 只打印堆栈信息的调用层次
(gdb) thread apply all bt

# 只打印堆栈信息的调用层次
(gdb) thread apply all where

示例:

(gdb) thread apply all bt

Thread 2 (Thread 0x7ffff6f42700 (LWP 1553)):
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004019d7 in ShmManager::threadFunc (this=0x61fc20) at shm_manager_sim.cpp:49
#3  0x0000000000401841 in ShmManager::<lambda()>::operator()(void) const (
    __closure=0x61fc68) at shm_manager_sim.cpp:28
#4  0x0000000000401e74 in std::_Bind_simple<ShmManager::start()::<lambda()>()>::_M_invoke<>(std::_Index_tuple<>) (this=0x61fc68) at /usr/include/c++/6/functional:1391
#5  0x0000000000401dfe in std::_Bind_simple<ShmManager::start()::<lambda()>()>::operator()(void) (this=0x61fc68) at /usr/include/c++/6/functional:1380
#6  0x0000000000401dce in std::thread::_State_impl<std::_Bind_simple<ShmManager::start()::<lambda()>()> >::_M_run(void) (this=0x61fc60) at /usr/include/c++/6/thread:197
#7  0x00007ffff7b0857f in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#8  0x00007ffff761d6ba in start_thread (arg=0x7ffff6f42700) at pthread_create.c:333
#9  0x00007ffff735341d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7ffff7fce740 (LWP 1549)):
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004010ad in main () at main.cpp:11
(gdb) thread apply all where

Thread 2 (Thread 0x7ffff6f42700 (LWP 1553)):
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004019d7 in ShmManager::threadFunc (this=0x61fc20) at shm_manager_sim.cpp:49
#3  0x0000000000401841 in ShmManager::<lambda()>::operator()(void) const (
    __closure=0x61fc68) at shm_manager_sim.cpp:28
#4  0x0000000000401e74 in std::_Bind_simple<ShmManager::start()::<lambda()>()>::_M_invoke<>(std::_Index_tuple<>) (this=0x61fc68) at /usr/include/c++/6/functional:1391
#5  0x0000000000401dfe in std::_Bind_simple<ShmManager::start()::<lambda()>()>::operator()(void) (this=0x61fc68) at /usr/include/c++/6/functional:1380
#6  0x0000000000401dce in std::thread::_State_impl<std::_Bind_simple<ShmManager::start()::<lambda()>()> >::_M_run(void) (this=0x61fc60) at /usr/include/c++/6/thread:197
#7  0x00007ffff7b0857f in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#8  0x00007ffff761d6ba in start_thread (arg=0x7ffff6f42700) at pthread_create.c:333
#9  0x00007ffff735341d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7ffff7fce740 (LWP 1549)):
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004010ad in main () at main.cpp:11
  • 查看指定线程的堆栈信息

命令:

# 先切换到指定线程,线程ID为gdb自定义的
(gdb) thread <thread-id-by-gdb>
# 只打印堆栈信息的调用层次
(gdb) bt

示例:

(gdb) thread 2
[Switching to thread 2 (Thread 0x7ffff6f42700 (LWP 1553))]
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
84	in ../sysdeps/unix/syscall-template.S
(gdb) bt
#0  0x00007ffff7626c1d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x0000000000401633 in std::this_thread::sleep_for<double, std::ratio<1l, 1000l> > (
    __rtime=...) at /usr/include/c++/6/thread:323
#2  0x00000000004019d7 in ShmManager::threadFunc (this=0x61fc20) at shm_manager_sim.cpp:49
#3  0x0000000000401841 in ShmManager::<lambda()>::operator()(void) const (
    __closure=0x61fc68) at shm_manager_sim.cpp:28
#4  0x0000000000401e74 in std::_Bind_simple<ShmManager::start()::<lambda()>()>::_M_invoke<>(std::_Index_tuple<>) (this=0x61fc68) at /usr/include/c++/6/functional:1391
#5  0x0000000000401dfe in std::_Bind_simple<ShmManager::start()::<lambda()>()>::operator()(void) (this=0x61fc68) at /usr/include/c++/6/functional:1380
#6  0x0000000000401dce in std::thread::_State_impl<std::_Bind_simple<ShmManager::start()::<lambda()>()> >::_M_run(void) (this=0x61fc60) at /usr/include/c++/6/thread:197
#7  0x00007ffff7b0857f in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#8  0x00007ffff761d6ba in start_thread (arg=0x7ffff6f42700) at pthread_create.c:333
#9  0x00007ffff735341d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

返回上一级


查看/设置源码的搜索路径

  • 查看源码搜索路径

命令:

(gdb) show directories

示例:

(gdb) show directories 
Source directories searched: $cdir:$cwd
  • 添加源码搜索路径

命令:

# source-code-path 为要添加的源码搜索路径
(gdb) directory <source-code-path>

示例:

# 添加源码搜索路径为 /usr/include/boost/
(gdb) directory /usr/include/boost/
Source directories searched: /usr/include/boost:$cdir:$cwd
  • 重置为默认的源码搜索路径

命令:

(gdb) directory

示例:

(gdb) directory
Reinitialize source path to empty? (y or n) y
Source directories searched: $cdir:$cwd

返回上一级


查看源码/汇编

注意: 要查看源码,需要在编译时带-g选项。

  • 查看当前文件的源码

命令:

(gdb) list <line-number>

示例:

(gdb) list 1
warning: Source file is more recent than executable.
1	#include "shm_manager_sim.h"
2	#include "topic_manager_sim.h"
3	
4	int main()
5	
6	    TopicManager::instance();
7	
8	    ShmManager::instance()->start();
9	
10	    while(true)
  • 查看指定文件的源码

命令:

(gdb) list <file-name>:<line-number>

示例:

(gdb) list shm_manager_sim.h:10
5	#include <thread>
6	
7	class ShmManager;
8	typedef std::shared_ptr<ShmManager> ShmManagerPtr;
9	
10	class ShmManager
11	
12	public:
13	    static const ShmManagerPtr& instance();
14	    void start();
  • 上翻/下翻源码

命令:

# 上翻源码
(gdb) list -
# 下翻源码
(gdb) list

示例:

(gdb) list shm_manager_sim.h:10
5	#include <thread>
6	
7	class ShmManager;
8	typedef std::shared_ptr<ShmManager> ShmManagerPtr;
9	
10	class ShmManager
11	
12	public:
13	    static const ShmManagerPtr& instance();
14	    void start();
(gdb) list -
1	#ifndef ROS_SHM_MANAGER_H
2	#define ROS_SHM_MANAGER_H
3	
4	#include <memory>
(gdb) list
5	#include <thread>
6	
7	class ShmManager;
8	typedef std::shared_ptr<ShmManager> ShmManagerPtr;
9	
10	class ShmManager
11	
12	public:
13	    static const ShmManagerPtr& instance();
14	    void start();
  • 查看指定函数的汇编代码

命令:

# 只打印汇编代码
(gdb) disas <function-name>
# 打印汇编代码和对应的源码
(gdb) disas /m <function-name>

示例:

(gdb) disas main
Dump of assembler code for function main():
   0x0000000000401046 <+0>:	push   %rbp
   0x0000000000401047 <+1>:	mov    %rsp,%rbp
   0x000000000040104a <+4>:	sub    $0x20,%rsp
   0x000000000040104e <+8>:	mov    %fs:0x28,%rax
   0x0000000000401057 <+17>:	mov    %rax,-0x8(%rbp)
   0x000000000040105b <+21>:	xor    %eax,%eax
   0x000000000040105d <+23>:	callq  0x405248 <TopicManager::instance()>
   0x0000000000401062 <+28>:	callq  0x401776 <ShmManager::instance()>
   0x0000000000401067 <+33>:	mov    %rax,%rdi
   0x000000000040106a <+36>:	callq  0x401172 <std::__shared_ptr<ShmManager, (__gnu_cxx::_Lock_policy)2>::operator->()
   const>
   0x000000000040106f <+41>:	mov    %rax,%rdi
   0x0000000000401072 <+44>:	callq  0x40184a <ShmManager::start()>
...
(gdb) disas /m main
Dump of assembler code for function main():
5	
   0x0000000000401046 <+0>:	push   %rbp
   0x0000000000401047 <+1>:	mov    %rsp,%rbp
   0x000000000040104a <+4>:	sub    $0x20,%rsp
   0x000000000040104e <+8>:	mov    %fs:0x28,%rax
   0x0000000000401057 <+17>:	mov    %rax,-0x8(%rbp)
   0x000000000040105b <+21>:	xor    %eax,%eax

6	    TopicManager::instance();
   0x000000000040105d <+23>:	callq  0x405248 <TopicManager::instance()>

7	
8	    ShmManager::instance()->start();
   0x0000000000401062 <+28>:	callq  0x401776 <ShmManager::instance()>
   0x0000000000401067 <+33>:	mov    %rax,%rdi
   0x000000000040106a <+36>:	callq  0x401172 <std::__shared_ptr<ShmManager, (__gnu_cxx::_Lock_policy)2>::operator->() const>
   0x000000000040106f <+41>:	mov    %rax,%rdi
   0x0000000000401072 <+44>:	callq  0x40184a <ShmManager::start()>
...

返回上一级


查看/设置/调试断点

  • 添加断点(所有线程)

命令:

(gdb) b <file-name>:<line-number>

示例:

(gdb) b main.cpp:13
Breakpoint 2 at 0x40108c: file main.cpp, line 13.
  • 添加断点(指定线程)

命令:

(gdb) b <file-name>:<line-number> thread <thread-id-by-gdb>

示例:

(gdb) b main.cpp:13 thread 1
Breakpoint 5 at 0x40108c: file main.cpp, line 13.
  • 在指定的内存地址添加断点

命令:

(gdb) b *<address>

示例:

(gdb) b *0x00000000004010a1
Breakpoint 7 at 0x4010a1: file main.cpp, line 13.
  • 添加条件断点

命令:

(gdb) b <file-name>:<line-number> if <expresion>

示例:

(gdb) b main.cpp:14 if TopicManager::instance()->getNumSubscriptions() > 1000
Breakpoint 6 at 0x4010b2: file main.cpp, line 14.
(gdb) i breakpoints 
Num     Type           Disp Enb Address            What
5       breakpoint     keep y   0x000000000040108c in main() at main.cpp:13 thread 1
	stop only in thread 1
6       breakpoint     keep y   0x00000000004010b2 in main() at main.cpp:14
	stop only if TopicManager::instance()->getNumSubscriptions() > 1000
  • 查看所有断点

命令:

(gdb) i breakpoints

示例:

(gdb) i breakpoints 
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x000000000040108c in main() at main.cpp:13
3       breakpoint     keep y   0x000000000040105d in main() at main.cpp:6
  • 查看指定断点

命令:

(gdb) i breakpoints <breakpoint-number>

示例:

(gdb) i breakpoints 2
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x000000000040108c in main() at main.cpp:13
  • 查看指定范围的断点

命令:

(gdb) i breakpoints <breakpoint-number>-<breakpoint-number>

示例:

(gdb) i breakpoints 2-3
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x000000000040108c in main() at main.cpp:13
3       breakpoint     keep y   0x000000000040105d in main() at main.cpp:6
  • 删除所有断点

命令:

(gdb) d

示例:

(gdb) d
Delete all breakpoints? (y or n) y
(gdb) i breakpoints 
No breakpoints or watchpoints.
  • 删除指定断点

命令:

(gdb) d breakpoints <breakpoint-number>

示例:

(gdb) i breakpoints 
Num     Type           Disp Enb Address            What
4       breakpoint     keep y   0x000000000040108c in main() at main.cpp:16
5       breakpoint     keep y   0x000000000040105d in main() at main.cpp:8
(gdb) d breakpoints 4
(gdb) i breakpoints 
Num     Type           Disp Enb Address            What
5       breakpoint     keep y   0x000000000040105d in main() at main.cpp:8
  • 删除指定范围的断点

命令:

(gdb) d breakpoints <breakpoint-number>-<breakpoint-number>

示例:

(gdb) i breakpoints 
Num     Type           Disp Enb Address            What
5       breakpoint     keep y   0x000000000040108c in main() at main.cpp:13 thread 1
	stop only in thread 1
6       breakpoint     keep y   0x00000000004010b2 in main() at main.cpp:14
	stop only if TopicManager::instance()->getNumSubscriptions() > 1000
(gdb) d 5-6
(gdb) i breakpoints 
No breakpoints or watchpoints.
  • 单步调试(语句级别)

命令:

# next命令可缩写为n
(gdb) next

示例:

(gdb) l
4	L_Subscription getAllSubscription();
5	
6	TopicManagerPtr g_topic_manager;
7	std::mutex g_topic_manager_mutex;
8	const TopicManagerPtr& TopicManager::instance()
9	
10	    if (!g_topic_manager)
11	    
12	        std::lock_guard<std::mutex> lock(g_topic_manager_mutex);
13	        if (!g_topic_manager)
(gdb) n
10	    if (!g_topic_manager)
(gdb) n
19	    return g_topic_manager;
  • 单步调试(指令级别)

命令:

# nexti命令可缩写为ni
(gdb) nexti

示例:

(gdb) ni
0x0000000000405265	10	    if (!g_topic_manager)
(gdb) ni
0x000000000040526a	10	    if (!g_topic_manager)
  • 跳入函数(语句级别)

命令:

# step命令可缩写为s
(gdb) step

示例:

(gdb) c
Continuing.

Thread 1 "main" hit Breakpoint 6, main () at main.cpp:14
14	        if (TopicManager::instance()->getNumSubscriptions() > 1000)
(gdb) s
TopicManager::instance () at topic_manager_sim.cpp:9
9	
(gdb) l
4	L_Subscription getAllSubscription();
5	
6	TopicManagerPtr g_topic_manager;
7	std::mutex g_topic_manager_mutex;
8	const TopicManagerPtr& TopicManager::instance()
9	
10	    if (!g_topic_manager)
11	    
12	        std::lock_guard<std::mutex> lock(g_topic_manager_mutex);
13	        if (!g_topic_manager)
  • 跳入函数(指令级别)

命令:

# stepi命令可缩写为si
(gdb) stepi

示例:

(gdb) si
TopicManager::instance () at topic_manager_sim.cpp:9
  • 跳出函数

命令:

(gdb) finish

示例:

(gdb) s
TopicManager::instance () at topic_manager_sim.cpp:9
9	
(gdb) finish 
Run till exit from #0  TopicManager::instance () at topic_manager_sim.cpp:9
0x00000000004010b7 in main () at main.cpp:14
14	        if (TopicManager::instance()->getNumSubscriptions() > 1000)
Value returned is $2 = 
  std::shared_ptr<TopicManager> (use count 1, weak count 0) = get() = 0x620c30
  • 继续执行

命令:

# continue命令可缩写为c
(gdb) continue

示例:

(gdb) c
Continuing.

Thread 1 "main" hit Breakpoint 6, main () at main.cpp:14
14	        if (TopicManager::instance()->getNumSubscriptions() > 1000)

返回上一级


打印/更改变量的值

  • 打印变量的值(只打印一次)

命令:

# print命令可缩写为p
(gdb) print <variable-name>

示例:

(gdb) p g_shm_manager
$3 = std::shared_ptr<ShmManager> (use count 1, weak count 0) = get() = 0x620c80
  • 打印变量的值(自动打印)

命令:

(gdb) display <variable-name>

示例:

(gdb) display g_shm_manager
1: g_shm_manager = std::shared_ptr<ShmManager> (use count 1, weak count 0) = get() = 0x620c80
(gdb) n
13	        std::this_thread::sleep_for(std::chrono::duration<double, std::milli>(10));
1: g_shm_manager = std::shared_ptr<ShmManager> (use count 1, weak count 0) = get() = 0x620c80
  • 更改变量的值

命令:

(gdb) p <variable-name>=<new-value>

示例:

(gdb) p g_shm_manager._M_ptr
$5 = (ShmManager *) 0x620c80
(gdb) p g_shm_manager._M_ptr=0
$6 = (ShmManager *) 0x0

返回上一级


打印函数参数/局部变量的值

  • 打印函数参数的值

命令:

(gdb) i args
  • 打印局部变量的值

命令:

(gdb) i locals

返回上一级


查看/更改寄存器的值

  • 查看常见寄存器的值

命令:

(gdb) i registers

示例:

(gdb) i registers 
rax            0x0	0
rbx            0x0	0
rcx            0x7ffff7626c1d	140737343810589
rdx            0x0	0
rsi            0x7fffffffd8e0	140737488345312
rdi            0x0	0
rbp            0x7fffffffd930	0x7fffffffd930
rsp            0x7fffffffd910	0x7fffffffd910
r8             0x0	0
r9             0x7ffff6f42700	140737336583936
r10            0x1381	4993
r11            0x0	0
r12            0x400f50	4198224
r13            0x7fffffffda10	140737488345616
r14            0x0	0
r15            0x0	0
rip            0x4010b2	0x4010b2 <main()+108>
eflags         0x246	[ PF ZF IF ]
cs             0x33	51
ss             0x2b	43
ds             0x0	0
es             0x0	0
fs             0x0	0
gs             0x0	0
  • 查看所有寄存器的值

命令:

(gdb) i registers all
  • 查看指定寄存器的值

命令:

(gdb) p $<register-name>

示例:

(gdb) p $rcx
$9 = 140737343810589
  • 更改指定寄存器的值

命令:

(gdb) p $<register-name>=<new-value>

示例:

(gdb) p $rcx
$9 = 140737343810589
(gdb) p $rcx=1
$10 = 1
(gdb) p $rcx
$11 = 1

返回上一级


查看内存的值

  • 查看内存的值

命令:

(gdb) x/<n><f><u> <address>

注:

  • n 表示要打印多少个单元(1个单元是指即参数u所指定的字节数),默认值为1。如果为正数,那么打印从地址addr后面的;否则打印从地址addr前面的。

  • f 表示输出格式,默认值为x(十六进制)。其他可选值:i,机器指令,忽略输出单元的大小;d,(有符号的)十进制;u,(无符号的)十进制;o,八进制;t,二进制;a,十六进制,省略最前面的0;s,字符串,且默认输出单元大小为b(bytes)。

  • u 表示输出单元大小,默认值为w(Words,4 bytes)。其他可选值:b,bytes;h,Halfwords,2 bytes;g,Giant words,8 bytes。**注意:**执行命令x时,如果没有显示指定输出单元大小,会默认使用上次所指定的值。

示例:

# 查看起始地址为0x7fb00008f0后面的4字节的内容,并以十六进制的格式输出
(gdb) x/wx 0x7fb00008f0

返回上一级


调用C/C++函数

  • 调用C/C++函数

命令:

(gdb) call <function-name>

示例:

(gdb) call TopicManager::instance()->subscribe()
$13 = true

返回上一级

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