Python 用于调试 stdlib 变量的漂亮打印机将无法工作

Question

我按照这个 post 以一种漂亮的方式调试变量 The value of strings doesn't appear in eclipse mars CDT

然而我最终得到如下错误信息：

 File "/usr/share/gdb/auto-load/usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.19-gdb.py", line 63, in <module>
    from libstdcxx.v6.printers import register_libstdcxx_printers
ImportError: No module named 'libstdcxx'

我该如何解决这个问题？

Answer 1

看起来您的 .gdbinit 没有正确的内容，或者不是运行。

确保添加的路径对您的机器是正确的，并且 gdbinit 文件是运行ning。

由于出现该错误，应该只需要将正确的路径添加到 python。

这是一个示例跟踪，它首先不起作用，然后在更正路径后起作用：

$ cat hello.cc 
#include <string>
using namespace std;

int main() {
    string mystring = "my string here";
    return 0;
}

$ g++ hello.cc -g -o hello.elf

$ gdb hello.elf --quiet

Reading symbols from hello.elf...done.
(gdb) b hello.cc:6
Breakpoint 1 at 0x400863: file hello.cc, line 6.
(gdb) r
Starting program: /tmp/x/hello.elf 
Traceback (most recent call last):
  File "/usr/share/gdb/auto-load/usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.19-gdb.py", line 63, in <module>
    from libstdcxx.v6.printers import register_libstdcxx_printers
ImportError: No module named 'libstdcxx'

Breakpoint 1, main () at hello.cc:6
6       return 0;
(gdb) p mystring
 = {static npos = <optimised out>, _M_dataplus = {<std::allocator<char>> = {<__gnu_cxx::new_allocator<char>> = {<No data fields>}, <No data fields>}, 
    _M_p = 0x602028 "my string here"}}
(gdb) python
>import sys
>sys.path.insert(0, '/usr/share/gcc-4.8/python/')
>end
(gdb) r
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Starting program: /tmp/x/hello.elf 

Breakpoint 1, main () at hello.cc:6
6       return 0;
(gdb) p mystring
 = "my string here"
(gdb)

以上示例的版本信息：

$ g++ --version
g++ (Ubuntu 4.8.4-2ubuntu1~14.04) 4.8.4
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ gdb --version
GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.2) 7.7.1
Copyright (C) 2014 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 "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word".

使用 Eclipse 时CDT

使用 Eclipse CDT 时需要手动指定 gdbinit 文件。 Eclipse CDT 使用 --nx 标志启动 GDB，这会阻止 GDB 自动获取任何 .gdbinit 文件。相反，您应该在启动配置中指定 CDT 适当的初始化文件：

此外，您可以在“首选项”中为新的启动配置更改默认启动 gdbinit，如此对话框所示：

Python 用于调试 stdlib 变量的漂亮打印机将无法工作

Python pretty printer for debugging stdlib variables won't work

python

printing

debugging

gdb

使用 Eclipse 时CDT