Strange exception

General JUCE discussion
1

I can’t remember getting this exception before… I have installed iTunes and I have uninstalled BoundsChecker. Maybe it has something to do with that, although I don’t get the exception in other apps.

This line if (pDataObject->GetData (&format, &medium) == S_OK)
in juce_win32_Windowing.cpp causes an exception as soon as I try to drag a file from my Desktop over my JUCE app. The exception is “0x000006b5 The interface is unknown”.

2

Funnily enough, this does not happen in the JUCE demo app, but only in my app.

[Edit: Wrong, it actually does happen in all JUCE apps on XP64, but on XP I don’t get the exception in any JUCE app.]

3

It seems to be the object at the other end that’s causing the problem… I’ve no idea what could be happening there, sorry!

4

Change that line to these lines and see if it helps:

            void **result;
            if (pDataObject->QueryInterface (IID_IDataObject, &result) == S_OK
                && pDataObject->GetData (&format, &medium) == S_OK)
5

You probably meant:

void *result; if (pDataObject->QueryInterface (IID_IDataObject, &result) == S_OK && pDataObject->GetData (&format, &medium) == S_OK)
But no, it doesn’t help. Furthermore, the exception happens in ALL JUCE apps, including the JUCE Demo from the tip. It’s just that I had exceptions turned off in the other projects, but the exception actually still shows up in Visual Studio’s logger. I want to stress out that this is on XP64. On XP32 (my other machine), when you drag a file over the app, instead of producing and exception, the logger will show the following 2 lines:

Unloaded c:\windows\system32\winsta.dll Unloaded c:\windows\system32\netapi32.dll"
So, it seems as if on my XP64, something goes wrong there?
I’ve checked, and both DLLs are present on XP64, in both system dirs (system32 & SysWOW64).

6

Could it just be an internal exception inside a windows DLL? That might be just the way it’s supposed to work, and you’re only noticing it because the debugger is catching all exceptions, even the deliberate ones?

7

Yes, absolutely. The exception happens inside kernel32.dll and if I shut off the Win32 exceptions it’s all fine (apart from the error in the Logger nothing impairs the actual experience of the app). I was just wondering why this happens.

8

Oh! Dude…I thought you somehow got an IUnknown that snuck past Juce without supporting the IDataObject interface!