在GDB中创建C ++字符串 [英] Creating C++ string in GDB

问题描述

我无法在GDB中创建 std :: string （或任何C ++对象）。我尝试了很多变化，以下并没有一个似乎工作：

pre $ g $ c pd std :: string（ hello）
表达式中的语法错误，靠近hello）。

有没有办法做到这一点？

< （我很惊讶，我在Web上找不到任何东西，我开始考虑我的GDB是否有问题，或者我做错了什么。）

$ $ $ $ $ $ $ $ $ $ $（$）$（$） void *）0x91a6a0
（gdb）call（（std :: string *）0x91a6a0） - > basic_string（）
（gdb）call（（std :: string *）0x91a6a0） - > assign （Hello，World）
$ 2 =（std :: basic_string< char，std :: char_traits< char> ;, std :: allocator< char>&;）@ 0x91a6a0：{static npos =<优化出>，_M_dataplus = {< std :: allocator< char>> = {< __ gnu_cxx :: new_allocator< char>> = {<没有数据字段>}，<没有数据字段>}，_M_p = 0x91a6f8Hello，World}}
（gdb）call SomeFunctionThatTakesAConstStringRef（*（const std :: string *）0x91a6a0）

I'm having trouble creating an std::string (or any C++ object, I guess) in GDB. I tried lots of variations to the following and none of them seem to work:

(gdb) p std::string("hello")
A syntax error in expression, near `"hello")'.

Is there a way to do it?

(I'm surprised I couldn't find anything about this on the Web. I'm starting to think if my GDB is buggy or I'm doing something very wrong.)

解决方案

You should be able to construct a new std::string within the GDB. You want to allocate space on the heap to hold the std::string object, invoke the default constructor, and assign your string value. Here is an example:

(gdb) call malloc(sizeof(std::string))
$1 = (void *) 0x91a6a0
(gdb) call ((std::string*)0x91a6a0)->basic_string()
(gdb) call ((std::string*)0x91a6a0)->assign("Hello, World")
$2 = (std::basic_string<char, std::char_traits<char>, std::allocator<char> > &) @0x91a6a0: {static npos = <optimized out>, _M_dataplus = {<std::allocator<char>> = {<__gnu_cxx::new_allocator<char>> = {<No data fields>}, <No data fields>}, _M_p = 0x91a6f8 "Hello, World"}}
(gdb) call SomeFunctionThatTakesAConstStringRef(*(const std::string*)0x91a6a0)

这篇关于在GDB中创建C ++字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！