Using windbg from Visual Studio - debugging

Is it possible to use windbg commands like !locks and .loadby sos mscorwks from the Visual Studio command window (in a debug session)? I've noticed I can use eg k to print a stack trace, so I was wondering if there is some way to get access to the other commands.

Yes you can do this.
Attach Visual studio 2008 to your process for debugging.
Break at some code.
Go to immediate window
type !load sos
Now you are free to use any of the windbg commands like !EEHeap,!DumpHeap
There are some conditions. You need to enable unmanaged code debugging in your project properties. Normally in 64 bit version studio doesn't support this.
Have fun.

Visual Studio 2012 has the "Windows User Mode Debugger" transport in the "Attach to Process" dialog. This allows you to use windbg commands in the immediate window.
Source: Use the WinDbg Engine in Visual Studio User-Mode Debugging

Starting with Windows Driver Development Kit (WDK) 8.0 the Windows debugger is integrated into Visual Studio (see Debugging Environments). Installing the WDK on top of a Visual Studio installation will enable a developer to pick a number of debuggers from the Attach to Process dialog, or set the debugging engine in a project's Debugger settings. This has been verified for Visual Studio 2012 and 2013. The way I read the MSDN link above, this should also work for any other IDE that is supported by the WDK 8.0 and above.
While WinDbg offers a lot of powerful commands, there are some drawbacks as well. This list is not exhaustive, and merely contains those issues I did encounter:
Cannot attach to more than one process at a time. While not generally an issue, this is quite unfortunate, if you do need to debug more than one process at a time. The Visual Studio debugger can attach to any number of processes simultaneously.
WinDbg will not use the symbol settings from your Visual Studio IDE (tested on VS 2012 Update 4). While you can configure the IDE where to look for debugging symbols, WinDbg will not honor those settings. WinDbg will use the _NT_SYMBOL_PATH environment variable, and/or the configuration set through .sympath.
Different syntax for function breakpoints. This is a minor annoyance, since you cannot use Visual Studio's syntax to specify function breakpoints. This also means, that function breakpoints are ignored that have been set using the Visual Studio syntax. What's more annoying, though, you do get a warning dialog for each when launching a debuggee.
No support for Tracepoints. I've been using tracepoints extensively, to unintrusively insert tracing into a debuggee. If you are using tracepoints as well, this may prove to be more than just an annoyance.

Related

Debugging C++ with Visual Studio debugger

I want to write an extension for Visual Studio Code (VSCode) which will allow me to debug a C++ program with Visual Studio's native C++ debugger instead of gdb (which currently is the only option VSCode supports). I looked at the Visual Studio Debugger Extensibility. But it only explains how you can create a new debug engine and call it from Visual Studio as a front end. What I want to do is the opposite. I want to call the existing Visual Studio C++ debug engine from a different front end, which happens to be VSCode. There is no documentation on the Internet how I can achieve this. Can anyone please help?
I'm on the VSCode team. To use the VS debugger from VSCode, you will need to author a debug adapter extension. Here's some documentation on getting started, and here's the complete debug adapter protocol reference.
Try look at some existing implementations to get started:
Mock debugger – simple example debugger
Node debugger - node.js debug adapter
For C++, also check out C++ tools for VSCode.
Hope that helps.
Edit - Seems I misunderstood the problem. Here are some thoughts on consuming the VS C++ debugger from an external application.
To my knowledge, Visual C++ does not have public APIs or interfaces that allows external programs to easily interface with them. Other languages have better stories, since they often leverage external libraries or were designed with documented debugger protocols. The GDB machine interface is a good example of this sort of design.
My best suggestion is that you could try to leverage the Visual Studio Env.DTE interfaces to control VS programmatically. EnvDTE is not well documented and may not be exactly what you are after, but it is pretty powerful.

Disable Visual Studio Special Debugging Features

I am new to Visual Studio, so I am used to IntelliJ and Eclipse style of functioning. I usually do not use a debugger when I develop, so I do not want to use it in Visual Studio too.
Is it possible to disable all special debugging functionalities which Visual Studio provides when you start your application? I want to have only normal output for the errors. When I disable all debugging, then I do not have usual output too, so this is not an option.
I tried many settings, but nothing seems to work and give me the results I want - no extra popup windows, no shiny layout changes when you have an error, just ordinary output.
Thanks!
Everyone's definition of "normal output" is different. Personally, I like the way Visual Studio handles debugging.
The console window in Visual Studio is a debugger feature and hence that is why it doesn't work when it's not attached to the process. If you want a stack trace without attaching, you could use your language/framework's built-in facilities such as an Exception or StackTrace in the case of .NET. You could also have Windows write a crash dump, but then you are debugging the corpse inside of Visual Studio.

Can I get reverse debugging functionality for Visual Studio 2013 Professional?

I know that GDB comes with reverse debugging, but is there a way I can get this functionality in Visual Studio 2013 Pro?
Visual Studio (2010, 2012, 2013 Ultimate only) does have a feature that allows you to step backwards from a breakpoint or exception (Intellitrace), and the values in the Locals and Autos panes (as well as DataTips that appear on a hover over a statement) will the show the state at that (previous) point. Unfortunately, Intellitrace is not available for 2013 Professional. In addition, it has only limited support for F# and does not support C++ or JavaScript.
Right now, (since no 3rd party extensions exist that I’m aware of) your best option is looking at the call stack to examine the source code that executed prior to the breakpoint or exception. BTW you can “drag” the debug point up and down in the debug gutter of the VS source window but this will only set the point of next execution (any previous state information is not displayed).
Since GDB does have this feature you could try something like VisualGDB or WinGDB, but I'm not sure how well reverse debugging is supported in either of these two or their stability once introduced into the most recent VS IDE.

How to disable symbol loading when debugging a Visual C++ program?

I am using Visual Studio 2008. I don't need to debug some DLLs in my project, so can I disable symbol loading when debugging a Visual C++ program? Does it help to make startup time faster when debugging?
The symbols are all local, so I don't have those slow loading problem, just want to make debugging faster and faster.
For example I am using Qt libraries, when I hit "Starting Debugging", the Output window shows that the symbols for Qt libraries are loaded. If VS can stop loading those symbols, the debugging startup time should be faster. Of course, I still want VS to load symbol for my executable.
Just found out that Visual Studio 2010 actually do what I want.
To load only the symbol for your executable file, without loading other symbols (eg: DLLs):
Go to Tools->Options->Debugging->Symbols
Click "Only specified modules"
Clear "Always load symbols located next to modules"
Click "Specify modules"
Click the new icon
Enter your executable filename (eg: my-awesome-app.exe)
Also found out that Visual Studio 2010 seems to perform better than Visual Studio 2008 when debugging. At least the IDE layout switches back faster when the debugging is stopped.
I am not sure what you mean by 'startup'. I assume you are talking about the launching of the actual application. The time to launch the target application is expensive regardless of mode you launch it. It may be less in Release but that will be negligible.
Turning off all symbol paths as mentioned in the other solution is a viable option. However, I am not sure why you are debugging if you do not want symbols for your launched application. Without the applications symbols you will not be able to see where you are in the source code when you are debugging.
If you are looking for a faster debugging experience you can use WinDbg. It comes with the Windows SDK but can also be downloaded seperately. If is a faster UI than Visual Studio, but it is much more cumbersome to use if you are more comfortable with a GUI. WinDbg uses commands to perform almost all tasks, but you can do some great debugging and it is faster in many cases compared to Visual Studio. In the event you want to debug C++\CLI or any managed application (e.g. C#), I would stick with Visual Studio. There is an extension in WinDbg called SOS, but it requires some advanced debugging experience to use correctly.

How to debug a process using Visual Studio?

If an application† crashes,
I hit "Debug" and Visual Studio is my currently registered Just-In-Time (JIT) debugger:
Visual Studio appears, but there's no way to debug anything:
I do not see any disassembly
I do not see any registers (assuming it runs on a CPU with registers)
The call stack is empty (assuming the CPU has a stack pointer)
I do not see any symbols (assuming it had any)
I do not see reconstructed source code from reflection (assuming it was managed)
Other JIT debugger products are able to show disassembly, but they are either command-line based (Debugging Tools for Windows), or do not support symbols (OllyDbg, Delphi). Additionally, my question is about debugging using Visual Studio, since I already have it installed, and it is already my registered JIT.
How do you debug a program using Visual Studio?
Alternatively: has anyone written a graphical debugger that supports the Microsoft symbol server?
† Not, necessarily, written in Visual Studio.
Edit: Changes title to process rather than application, since the latter somehow implies "my application."
Edit: Assume the original application was written in assembly language by Steve Gibson. That is, there is no source code or debug information. Visual Studio should still be able to show me an assembly dump.
Looking at the screenshot it appears that Visual Studio is currently debugging in Run mode - you need to break execution of the process before it makes sense to look at things like the call stack, etc...
To break execution of the process you either need to hit a breakpoint, or you can break execution of the process at any time by using the Pause / Break all toolbar item (Control + Alt + Break).
Then you should be able to access the following windows under the Debug -> Windows menu:
The disassembly window
The registers window
The call stack window
The modules window shows a list of loaded modules along with where their corresponding symbols are loaded from (if loaded)
Some other useful windows:
The processes window is useful if you are debugging more than one process at a time
The Threads window
The Memory window (there are four of them)
The Locals window
Some of these might not be visible by default depending on which window configuration you selected when you first started Visual Studio - if you can't find them then right click on the toolbar and goto customise to add them.
Visual studio doesn't reconstruct soucre code from disassembly - you really need to have the original source code available to you, otherwise the symbols almost certainly won't match the source code you are debugging.
If you are debugging unmanaged modules without source code then I recommend you at least try WinDbg - its user interface is a bit clunky at times, and it does have a steep learning curve, however it is a very powerful debugger supporting many features that Visual Studio doesn't - it may be more suited to the sort of debugging you need to do.
(Visual Studio is a fantastic debugger, however it's primarily used to debug modules where the source code is available and so it lacks certain features in favour of a better user experience).
Assuming this is your application that you wrote in VS, just press F5 to run the program and either use a breakpoint, or manually break the program to start debugging.
The problem in the last screenshot is that Visual Studio did not enter break mode automatically. That seems like a bug. If you hit the 'pause' button on the toolbar, it would enter break mode, giving you disassembly, and a callstack.
According to that last screenshot you were actually attached to the program ... the output windows shows it loaded stripped symbols for OLE and the crt.
You can debug a program with Visual Studio if you have the debug information available for this program. It's the difference between compiling a Release version (normally without debug information) and compiling a Debug version.
This dialog to debug a program is handy if you are testing the debug version of your self-written program. You can attach it "on-the-fly" to your Visual Studio debugger and look for the problem.
If it is not your program or it is your program, but does not provide debugging information which Visual Studio can understand, then you are out of luck.
Use menu Debug -> Windows -> Disassembly (I think the keyboard shortcut is Alt + 8, but I am configured for VC 6.0 bindings, because that's how I roll, and it may have changed).
You can get public symbols for the operating system from http://msdl.microsoft.com/download/symbols. Add it to the list in menu Tools -> Options -> Debugging -> Symbols -> Symbol file locations.
Also, make sure you are running in the same integrity level as the application. Or always run Visual Studio as Administrator.
I guess you are already in the Debug mode. The "Run" button is disabled. Just go to Debug -> windows -> Disassembly to view disassembly.

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