如何避免原生可视化程序中的递归

Question

我正在调试一个C++程序，该程序包含相当多的CPtrArray对象
使用自定义的heap_stat脚本，我知道CPtrArray对象的指针值，其中包含许多条目。

使用原生可视化器，我确实可以看到每个CPtrArray对象中的条目数量，因此我对应的natvis条目：

<Type Name="CArray&lt;*,*&gt;">
<AlternativeType Name="CPtrArray"/> 
<DisplayString>{{size = {m_nSize}}}</DisplayString> 

问题是：这显示了元素的数量，但没有显示指针值。我想很容易解决这个问题，使用以下natvis条目：

<Type Name="CArray&lt;*,*&gt;">
<AlternativeType Name="CPtrArray"/> 
<DisplayString>{{size = {m_nSize}, pointer = {this}}}</DisplayString> 

然而，这向我显示了指针值，但也显示了更多：：-(

{size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 {size = , pointer = }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}

有人知道我如何避免这种递归吗？

在第一条评论后编辑并回答

我对heap_stat脚本进行了如下调整：

if type_name.endswith("CPtrArray"):
collection_Size = typedVar('CPtrArray', ptr).m_nSize
...
dprintln(("0x" + pointer_format + "t%st Size:[%d]") % (ptr, type_name, collection_Size))

因此，我在heap_stat报告中得到了CPtrArray(和其他(对象的大小：

0x0732517c  mfc110u!CStringArray     Size:[0]
0x073256d4  mfc110u!CPtrArray    Size:[584]

我有COLUMN对象，它们具有CPtrArray属性，我想知道哪个对象与特定的CPtrArray对象相对应，因此我在监视窗口中添加了所有COLUMN对象：

((COLUMN*)0x073256d0)->paData   {size = 584, pointer = 0x073256d4 {size = 584, pointer = 0x073256d4 ...
((COLUMN*)0x07325780)->paData   {size = 0, pointer = 0x01234567 {size = 0, pointer = 0x01234567 ...
((COLUMN*)0x07325830)->paData   {size = 0, pointer = 0x02345678 {size = 0, pointer = 0x02345678 ...

正如你所看到的，递归给了我大量的信息(并大大降低了我的分析性能(，因此我希望避免它，而不需要扩展每个COLUMN对象来查看所需的信息。

经过一些后续操作后编辑

由于这个问题看起来像是Natvis处理中的一个bug，我决定在MSDN网站上写一篇重复的帖子。这篇文章最近被标记为"Triaged"，我希望这意味着MSDN开发人员会考虑它。

提前感谢

Answer 1

递归扩展之所以完成，是因为调试器知道this的类型是CArray，以及该类型应如何显示。如果你只想要一个没有扩展的指针，你可以像中那样将指针投射到void*，从而放弃CArray类型的知识

<DisplayString>{{size = {m_nSize}, pointer = {(void*)this}}}</DisplayString>

Answer 2

问题是您通过natvis要求递归地显示它。this将显示this的DisplayString，现在您有一个无限递归。实际上，很少有natvis文件的DisplayString中包含this。

相反，添加一个包含数组内容和其他内容的<Expand>节，这样就不会重复出现。

你可以显示指向数据的指针，这很容易实现，如果你想进行某种检查来识别相同的数组，但使用this，你将无法获得你想要的结果，因为它会用指针触发显示字符串。