Dear CPians: Help me out by voting for this
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I wrote a test application to validate my theory and it works. Of course, it can be improved a lot. The idea is to get the dll name and the address at which the access violation occured. I wrote a C++ dll called Crasher with a method that causes access violation:
extern "C" _declspec(dllexport) int _stdcall CrashMyApp()
{
char* sz = 0;
*sz = 0;return -1;}
Now I call this from a managed assemvbly and catch access violation and get more information:
static void Main(string[] args)
{
try
{
CrashMyApp();
}
catch (AccessViolationException)
{
IntPtr ex = Marshal.GetExceptionPointers();EXCEPTION\_POINTERS pointers = (EXCEPTION\_POINTERS)Marshal.PtrToStructure(ex, typeof(EXCEPTION\_POINTERS)); EXCEPTION\_RECORD rec = (EXCEPTION\_RECORD)Marshal.PtrToStructure(pointers.ExceptionRecord, typeof(EXCEPTION\_RECORD)); Console.WriteLine("Exception in {0} at {1:x8}", DllNameFromAddress(rec.ExceptionAddress), rec.ExceptionAddress.ToInt32()); // Usually you wil re-throw may be wrapping in some other exception // Bad idea to catch AccessViolationException and do nothing }}
All the utility methods are in the project download link at the bottom of the post. So the output is like this:
Exception in C:\Users\ramakrishna\Documents\Visual Studio 2008\Projects\UnmanagedDebugging\Debug\Crasher.dll at 77b71328
Download link here: Crasher.zip (8.5 KB) Of course, you can build a lot fancy stuff like load the symbols, generate mini-dumps etc.
Nice one Rama!
Daniel Vaughan Blog: DanielVaughan.Orpius.com
Company: Outcoder -
Probably it might be easier to put the code in an event handler for Application.ThreadException. That way you don't have to add individual try-catch blocks.
Probably even easier still to go to the beach with your family while MS does their danged jobs. ;P
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Dear CPians, Have you ever written a .NET desktop or web application that talks to a SQL database? Uses WinForms controls? Talks to COM objects? Talks to Win32 via P/Invoke? If so, you may have run into the dreaded AccessViolationException: Some managed code called into unmanaged code, and memory was corrupted. Maybe you passed a bad argument to the unmanaged function. Maybe there's a bug in the managed-to-native interop. Whatever the case, when it happens, all you get is an unhelpful message and a useless stack trace, making it near-impossible to debug. Please vote up this MSConnect case[^] so Microsoft gives us more information when these errors occur. If MS gives us more information, devs can fix crashing .NET apps, users will be happier, and the world will be a better place. Thank you.
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
+1
-
I wrote a test application to validate my theory and it works. Of course, it can be improved a lot. The idea is to get the dll name and the address at which the access violation occured. I wrote a C++ dll called Crasher with a method that causes access violation:
extern "C" _declspec(dllexport) int _stdcall CrashMyApp()
{
char* sz = 0;
*sz = 0;return -1;}
Now I call this from a managed assemvbly and catch access violation and get more information:
static void Main(string[] args)
{
try
{
CrashMyApp();
}
catch (AccessViolationException)
{
IntPtr ex = Marshal.GetExceptionPointers();EXCEPTION\_POINTERS pointers = (EXCEPTION\_POINTERS)Marshal.PtrToStructure(ex, typeof(EXCEPTION\_POINTERS)); EXCEPTION\_RECORD rec = (EXCEPTION\_RECORD)Marshal.PtrToStructure(pointers.ExceptionRecord, typeof(EXCEPTION\_RECORD)); Console.WriteLine("Exception in {0} at {1:x8}", DllNameFromAddress(rec.ExceptionAddress), rec.ExceptionAddress.ToInt32()); // Usually you wil re-throw may be wrapping in some other exception // Bad idea to catch AccessViolationException and do nothing }}
All the utility methods are in the project download link at the bottom of the post. So the output is like this:
Exception in C:\Users\ramakrishna\Documents\Visual Studio 2008\Projects\UnmanagedDebugging\Debug\Crasher.dll at 77b71328
Download link here: Crasher.zip (8.5 KB) Of course, you can build a lot fancy stuff like load the symbols, generate mini-dumps etc.
:thumbsup: very useful and thanks also to the gentleman suggesting an event handler approach; may code be forever cleaner and more readable with error handling out of the way :-D
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Dear CPians, Have you ever written a .NET desktop or web application that talks to a SQL database? Uses WinForms controls? Talks to COM objects? Talks to Win32 via P/Invoke? If so, you may have run into the dreaded AccessViolationException: Some managed code called into unmanaged code, and memory was corrupted. Maybe you passed a bad argument to the unmanaged function. Maybe there's a bug in the managed-to-native interop. Whatever the case, when it happens, all you get is an unhelpful message and a useless stack trace, making it near-impossible to debug. Please vote up this MSConnect case[^] so Microsoft gives us more information when these errors occur. If MS gives us more information, devs can fix crashing .NET apps, users will be happier, and the world will be a better place. Thank you.
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
I did my part.
PlutoX
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Hi Judah, Vote++; 12:50PM (GMT +7) best, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
Thanks, Bill!
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
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+1
Thanks!
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
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Voted it up. Well, due to these arbitrary difficulties in VC++/.NET, I over the years switched to PHP/MySQL after completing my span of being a workplace hero in Windows environment for half a decade. And I must say, I am much more happy and productive in PHP/MySQL environment :laugh: but seriously miss the challenging and real development of VC++ days. :(( - Pragmatic Programmer
Thanks, Shamit!
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
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I did my part.
PlutoX
Thank you!
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
-
Dear CPians, Have you ever written a .NET desktop or web application that talks to a SQL database? Uses WinForms controls? Talks to COM objects? Talks to Win32 via P/Invoke? If so, you may have run into the dreaded AccessViolationException: Some managed code called into unmanaged code, and memory was corrupted. Maybe you passed a bad argument to the unmanaged function. Maybe there's a bug in the managed-to-native interop. Whatever the case, when it happens, all you get is an unhelpful message and a useless stack trace, making it near-impossible to debug. Please vote up this MSConnect case[^] so Microsoft gives us more information when these errors occur. If MS gives us more information, devs can fix crashing .NET apps, users will be happier, and the world will be a better place. Thank you.
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
Added my vote ...
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Added my vote ...
Thank you, dog lover!
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
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Probably even easier still to go to the beach with your family while MS does their danged jobs. ;P
:laugh:
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango
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Should this be posted on connect as a workaround? :confused:
The latest nation. Procrastination.
Done, with rockstar Rama getting full credit.
Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango