前言 
gdbgolang
gdb安装 
brewgdb

更新brew

brew update

查看是否存在gdb镜像

brew search gdb

安装gdb

brew install gdb
go build编译 
go help build
go build -gcflags=all="-N -l" -ldflags=-compressdwarf=false

这里编译用到的参数含义解释如下：

编译参数含义
-gcflags=all="-N -l"关闭内联优化；关闭编译器函数优化
-ldflags=-compressdwarf=false生成压缩
gdb执行 
gdb maingdb
$ gdb program
Reading symbols from program...
Loading Go Runtime support.
gdb命令 
gdbgdb
命令说明
file <文件名>加载被调试的可执行程序文件
run重新开始运行文件，简写r
start单步执行，运行程序，停在第一执行语句
list查看源代码，简写l
set设置变量的值
next单步调试（逐过程，函数直接执行）,简写n
step单步调试（逐语句：跳入自定义函数内部执行）,简写s
backtrace查看函数的调用的栈帧和层级关系,简写bt
frame切换函数的栈帧,简写f
info查看函数内部局部变量的数值,简写i
finish结束当前函数，返回到函数调用点
continue继续运行,简写c
print打印值及地址,简写p
quit退出gdb,简写q
gdbhelp [command]
gdb调试

下面，基于一个简单的golang程序进行gdb调试，目的是了解golang程序的初始化流程。

listgo
(gdb) list
1       package main
2       
3       import "fmt"
4       
5       func main() {
6               fmt.Println("hello world")
7       }

info files
(gdb) info files
Symbols from "/Users/guanjian/workspace/go/program/program".
Local exec file:
        `/Users/guanjian/workspace/go/program/program', file type mach-o-x86-64.
        Entry point: 0x10701e0:
        0x0000000001001000 - 0x00000000010cbc53 is .text
        0x00000000010cbc60 - 0x00000000010cbd62 is __TEXT.__symbol_stub1
        0x00000000010cbd80 - 0x0000000001100b19 is __TEXT.__rodata
        0x0000000001100b20 - 0x00000000011012bc is __TEXT.__typelink
        0x00000000011012c0 - 0x0000000001101328 is __TEXT.__itablink
        0x0000000001101328 - 0x0000000001101328 is __TEXT.__gosymtab
        0x0000000001101340 - 0x000000000115dae8 is __TEXT.__gopclntab
        0x000000000115e000 - 0x000000000115e020 is __DATA.__go_buildinfo
        0x000000000115e020 - 0x000000000115e178 is __DATA.__nl_symbol_ptr
        0x000000000115e180 - 0x000000000116c4a4 is __DATA.__noptrdata
        0x000000000116c4c0 - 0x00000000011738f0 is .data
        0x0000000001173900 - 0x00000000011a1170 is .bss
        0x00000000011a1180 - 0x00000000011a62f0 is __DATA.__noptrbss
(gdb) 

Entry point: 0x10701e0:break *0x10701e0:
(gdb) break *0x10701e0
Breakpoint 1 at 0x10701e0: file /usr/local/go/src/runtime/rt0_darwin_amd64.s, line 8.

/usr/local/go/src/runtime/rt0_darwin_amd64.srt0.s
$ ls /usr/local/go/src/runtime/rt0_
rt0_aix_ppc64.s        rt0_ios_arm64.s        rt0_netbsd_arm.s
rt0_android_386.s      rt0_js_wasm.s          rt0_netbsd_arm64.s
rt0_android_amd64.s    rt0_linux_386.s        rt0_openbsd_386.s
rt0_android_arm.s      rt0_linux_amd64.s      rt0_openbsd_amd64.s
rt0_android_arm64.s    rt0_linux_arm.s        rt0_openbsd_arm.s
rt0_darwin_amd64.s     rt0_linux_arm64.s      rt0_openbsd_arm64.s
rt0_darwin_arm64.s     rt0_linux_mips64x.s    rt0_openbsd_mips64.s
rt0_dragonfly_amd64.s  rt0_linux_mipsx.s      rt0_plan9_386.s
rt0_freebsd_386.s      rt0_linux_ppc64.s      rt0_plan9_amd64.s
rt0_freebsd_amd64.s    rt0_linux_ppc64le.s    rt0_plan9_arm.s
rt0_freebsd_arm.s      rt0_linux_riscv64.s    rt0_solaris_amd64.s
rt0_freebsd_arm64.s    rt0_linux_s390x.s      rt0_windows_386.s
rt0_illumos_amd64.s    rt0_netbsd_386.s       rt0_windows_amd64.s
rt0_ios_amd64.s        rt0_netbsd_amd64.s     rt0_windows_arm.s

rt0_darwin_amd64.s
% cat -n rt0_darwin_amd64.s
     1	// Copyright 2009 The Go Authors. All rights reserved.
     2	// Use of this source code is governed by a BSD-style
     3	// license that can be found in the LICENSE file.
     4
     5	#include "textflag.h"
     6
     7	TEXT _rt0_amd64_darwin(SB),NOSPLIT,$-8
     8		JMP	_rt0_amd64(SB)	//这里上一步的断点位置
     9
    10	// When linking with -shared, this symbol is called when the shared library
    11	// is loaded.
    12	TEXT _rt0_amd64_darwin_lib(SB),NOSPLIT,$0
    13		JMP	_rt0_amd64_lib(SB)

_rt0_amd64(SB)
Breakpoint 1 at 0x10701e0: file /usr/local/go/src/runtime/rt0_darwin_amd64.s, line 8.

_rt0_amd64runtime/asm_amd64.sruntime·rt0_go(SB)runtime·rt0_go(SB)
TEXT runtime·rt0_go(SB),NOSPLIT,$0
...
// ===== 调用初始化函数 =====
CALL runtime·args(SB)
CALL runtime·osinit(SB)
CALL runtime·schedinit(SB)
// ===== 创建 main goroutine 用于执行 runtime.main =====
MOVQ $runtime·mainPC(SB), AX
PUSHQ AX
PUSHQ $0
CALL runtime·newproc(SB)
POPQ AX
POPQ AX
// ===== 让当前线程开始执行 main goroutine =====
CALL runtime·mstart(SB)
RET
DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)
GLOBL runtime·mainPC(SB),RODATA,$8

$runtime·main(SB)
(gdb) b runtime.main
Breakpoint 1 at 0x103b4c0: file /usr/local/go/src/runtime/proc.go, line 115.

gdb
问题整理
  • 问题1: macOs下gdb签名限制
(gdb) run
Starting program: /xxx/main 
Unable to find Mach task port for process-id 35564: (os/kern) failure (0x5).
(please check gdb is codesigned - see taskgated(8))

root
(gdb) list
(gdb) list
No symbol table is loaded.  Use the "file" command.

go build -ldflags=-compressdwarf=false
  • 问题3: 关于函数调用查找方法
 b [file].[method]info breakpoints
cat -n file | head -n [number]
参考

《Go语言学习笔记》雨痕
go build 命令参数详解
使用GDB调试Go语言
mac下如何对gdb进行证书签名
Go使用gdb调试
Debugging Go Code with GDB
使用 GDB 调试 Go 代码
【Go源码阅读】使用GDB调试Go程序
gdb命令
使用gdb添加断点的几种方式
gdb 初次运行卡住 Starting program: [New Thread 0x1103 of process 843]