嵌入式Linux之gdb配置和使用

背景：

ARM Cortext-A53核+Linux 4.1.12，内核空间64位，用户态32位，gdb版本7.10.1

GDB编译：

1）手动下载gdb-7.10.1.tar.gz源码编译

./configure --host=arm-buildroot-linux-gnueabi --target=arm-buildroot-linux-gnueabi CC=/opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.24-binutils-2.25/usr/bin/arm-buildroot-linux-gnueabi-gcc AR=/opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.24-binutils-2.25/usr/bin/arm-buildroot-linux-gnueabi-ar --prefix=<output path>

make

make install

标准的三步编译

 

 

目标板内置gdb

 

GDB Server

1.开发板编译
./configure --host=arm-buildroot-linux-gnueabi --target=arm-buildroot-linux-gnueabi --prefix CC=/opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.22-binutils-2.25/usr/bin/arm-buildroot-linux-gnueabi-gcc AR=/opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.22-binutils-2.25/usr/bin/arm-buildroot-linux-gnueabi-ar

2.主机端(192.168.1.251)
/opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.22-binutils-2.25/usr/bin/arm-buildroot-linux-gnueabi-gdb
target remote 192.168.1.108:3325
set sysroot /opt/toolchains/crosstools-arm-gcc-5.3-linux-4.1-glibc-2.22-binutils-2.25/usr/arm-buildroot-linux-gnueabi/sysroot

3.设备端（192.168.1.108）
./gdbserver 192.168.1.251:3325

(gdb) run

Starting program: /usr/local/test

warning: Unable to fetch general register.

PC register is not available

-----ptrace(PTRACE_GETREGSET)失败

(gdb) set libthread-db-search-path
(gdb) set auto-load libthread-db [on|off]
(gdb) info auto-load libthread-db
          No auto-loaded libthread-db.
(gdb) show auto-load libthread-db
          Auto-loading of inferior specific libthread_db is on.

/lib/libthread_db.so.1软链接指向/lib/libthread_db-1.0.so

如果缺少该库，报错如下：

warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.

同时，要保证该库没有被strip过，因为需要nptl_version符号，否则会报错：

Unable to find libthread_db matching inferior's thread library, ...

(gdb) run        
Starting program: /usr/local/test 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/libthread_db.so.1".
Cannot find user-level thread for LWP 130: generic error