Stop Debugger to Debug IL - debugging

My debugger keep jumping into debugging the IL instead of jumping to debug code of another assembly. How can I turn it off?

Visual Studio right?
Tools -> Options
Click the Debugging section then deselect the Show disassembly if source is not available checkbox
But that will leave you without any debug information if source is not available. It sounds like the debug information is missing from those assemblies. Maybe they were built in release mode? Or the pdb files have not been copied? Of course if you don't have access to the original source code then it won't make any difference

Related

Visual Studio 2012 - View items in the Stack while debugging

I'm using Visual Studio 2012 to write in assembly and I'm currently using the PUSH/POP instructions.
I would like to know where does sit the value being pushed to the stack by the PUSH instruction.
I've tried the Memory Tab by locating the ESP address but didn't find anything there.
Can please someone tell if it is possible and how to reach/locate the pushed values in debugging mode?
Thank you,
Guy
On the topmost toolbar in Visual Studio:
"Debug > Windows > CallStack"
Note that this is only available with the debugger attached to a process.
[Frames below may be incorrect and/or missing, no symbols loaded for
ntdll.dll]
MSDN article: Using the Call Stack.
That error message indicates there are no debug symbols available for the project to use. Make sure that you are in debug mode, not release.
Also if you are using "debug > attach to process" make sure the .pdb (symbol files) are available.
Either:
make sure the .PDB files for your DLLs are in the same directory as the process executable that you are attaching the debugger to.
OR
open Debug > Windows > Modules
Check Symbol Status ("Cannot find or open PDB file" means they aren't loaded)
Locate your DLL
Right click it and
select "Load Symbols From > Symbol Path"

Visual studio Attaching debugger to windows service - never hits the break points

I attach VS 2010 to service process; after that I put breakpoint in several methods but they never seem to be hit. Any idea or tips?
Note: The services process installed is a release build. Do I have to have a debug build installed for this?
You need to have a debug build for this.
In release mode, the debug info is discarded and code is optimized, so there is no way to link to original source code.
In debug mode, debugging and project state information is retained so the debugger canlink to the source code. It also emits DebuggableAttribute that tells JIT compiler that the assembly has debug info.
Helpful link: http://msdn.microsoft.com/en-us/library/ms241903.aspx

Visual C++: breakpoints disabled

I have a 'release with debug info' unmanaged c++ .exe (built with VS2005) deployed onto another PC, the .exe and .pdb are in the same folder.
When I try to attach to the process from VS2005, either locally or remotely from my dev PC, all my breakpoints become disabled. I don't get any warning/error popups which makes me think the PDB file is being found, but not seen as 'good'. Is that the right interpretation? I think if it couldn't see the PDB I'd get a "no debug information could be found" popup.
Has anyone got any ideas what can be wrong?
Check the output window - it should tell you if debug symbols are being found when the debugger attaches.
Are the breakpoints marked with a yellow exclamation mark triangle? This could be due to the PDB not corrresponding to the version of the source you're using. Right click on the breakpoint and select the option that allows the source code to be different (or rebuild your executable)
HTH
Seb
My best guess is that Visual Studio doesn't find the source code PDB files refer to. I am not able to look now, but I think you have the possibility to specify the location of the source code by hand in these cases (I don't have visual studio available at the moment).
The PDB was being generated, but another compiler setting meant nothing useful was being put inside it!

Stepping into a P/Invoke call in disassemby view

My C# code is calling an unmanaged third-party library function via P/Invoke, and the unmanaged function is having some strange side effects. I want to debug into it and see what it's doing.
If I debug my C# code, and try to "Step Into" the P/Invoke call, it steps over instead. No surprise there -- I expected that; it doesn't have the source for this DLL, and I didn't tell it I was okay with seeing the disassembly view.
So I switch the debugger to disassembly view (Debug > Windows > Disassembly). Now I see the individual x86 instructions in my JITted code. Again I try to step into the P/Invoke call. Again, it steps over instead -- even though I clearly told it to Step Into an x86 CALL instruction. How hard is it to step into an x86 CALL?
My Googling thus far has shown me a couple of options that can affect this, and I've already set them:
In Tools > Options > Debugging > General, "Enable Just My Code" is unchecked.
In Project > Properties > Debug tab, "Enable unmanaged code debugging" is checked.
No good. Visual Studio still refuses to step in.
I don't have a PDB for the third-party DLL, but that shouldn't matter. I don't care about source code or symbol information. (Well, actually they'd be really nice, but I already know I'm not going to get them.) Visual Studio can do x86 debugging (that's what the Disassembly view is for), and all I want to do is step into the x86 code.
What else do I need to do to get VS to allow me to step into the x86 instructions inside a P/Invoke call?
This may help you solve the problem:
(by Graviton)
CallingConvention = CallingConvention.Cdecl
Also this mentions that you need to detach managed debugger and re-attach unmanaged when crossing the boundaries. You might need to check the capabilities of mixed debugger and it's preferences from MSDN.
And finally, using Ed Dore' answer:
Under Tools.Options dialog, select the
Debugging category, and make sure the
"Enable Just My Code" setting is
unchecked. From the Project
properties, select the Debug tab, and
then ensure that "Enable unmanaged
code debugging" is checked.
Once you've got these squared away,
you should get the mixed mode
debugging support working.
Also, if you use "Debug.Attach To
Process" , be sure to hit the
"Select..." button in the "Attach To
Process" dialog, and select both
Managed and Native debugging support.
One thing I would try is going from C# to C++/CLI code, and then from C++ to the third-party code. Once you're in C++ (and free of the P/Invoke infrastructure), you might have better luck with the disassembly view.
In your C# project properties, in the Debug tab, check Enable native code debugging. Worked for me in VS 2012.
Credit goes to billb.
Also, since it's a third party library, ensure Enable Just My Code is unchecked in Options > Debugging.
I had a similar issue where I was debugging a C# exe that called my own C++ dll via PInvoke, all part of the same solution. Enabling native code debugging in my c# project allowed me to debug my C++ code.
Had same issue today.
What helped in my case was to run Visual Studio as administrator.
My setup:
Visual Studio 2019
Windows 10

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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