How to understand the call stack of Visual Studio?

Question

  VCamD.ax!CFactoryTemplate::CreateInstance()  + 0x3f bytes 
> VCamD.ax!CClassFactory::CreateInstance()  + 0x7f bytes 

What\'s 0x7f

Answer 1

You got .pdb files that were stripped. Their source code file and line number info was removed. Typical for example for .pdb files you can get from the Microsoft symbol server.

Which is okay, you can't get the source code anyway. Without the line number info, the debugger falls back to using the 'closest' symbol whose address it does have available, typically the function entry point, and adds the offset of the call instruction.

Sometimes you get bogus information if debug info is missing for long stretches of code. That 'closest' symbol is in no way related to the original code. Any time the offset gets to be larger than, oh, 0x200 then you ought to downplay the relevance of the displayed symbol name. There are a couple of places in the Windows code where you actually see the name of a string variable. The stack trace you posted has high confidence, those offsets are small.