Debugging program that is using the clipboard can cause VS to freeze

[einaregilsson]

from Markus Schaber (disqus)

Yesterday, I had problems while debugging, visual studio froze because the process being debugged was the clipboard owner (the bug I had to chase was about a paste operation).

It turned out that two extensions (AnkhSVN and ClipBoardDiff) did access the clipboard which did not respond because the owner was halted by the debugger on the exception I wanted to chase.

The AnkhSVN developer already committed a workaround which avoids accessing the clipboard in this specific case. (https://ctf.open.collab.net/sf... - which seemlingly also contains other fixes).

The "interesting" Part of the stack trace is:

System.Windows.Forms.dll!System.Windows.Forms.Clipboard.GetDataObject(int retryTimes, int retryDelay) + 0x1d bytes
System.Windows.Forms.dll!System.Windows.Forms.Clipboard.GetDataObject() + 0x4f bytes
System.Windows.Forms.dll!System.Windows.Forms.Clipboard.ContainsText(System.Windows.Forms.TextDataFormat format) + 0x33 bytes
System.Windows.Forms.dll!System.Windows.Forms.Clipboard.ContainsText() + 0x31 bytes
ClipboardDiff.dll!EinarEgilsson.ClipboardDiff.ClipboardDiffPackage.ClipboardAndSelectionBothHaveText() + 0xb bytes
ClipboardDiff.dll!EinarEgilsson.ClipboardDiff.ClipboardDiffPackage.InitializeMenuCommands.AnonymousMethod__2(object cmd, System.EventArgs e) + 0x2b bytes
Microsoft.VisualStudio.Shell.10.0.dll!Microsoft.VisualStudio.Shell.OleMenuCommand.OleStatus.get() + 0x2c bytes
Microsoft.VisualStudio.Shell.10.0.dll!Microsoft.VisualStudio.Shell.OleMenuCommandService.Microsoft.VisualStudio.OLE.Interop.IOleCommandTarget.QueryStatus(ref System.Guid guidGroup, uint nCmdId, Microsoft.VisualStudio.OLE.Interop.OLECMD[] oleCmd, System.IntPtr oleText) + 0xf0 bytes
Microsoft.VisualStudio.Shell.10.0.dll!Microsoft.VisualStudio.Shell.Package.Microsoft.VisualStudio.OLE.Interop.IOleCommandTarget.QueryStatus(ref System.Guid guidGroup, uint nCmdId, Microsoft.VisualStudio.OLE.Interop.OLECMD[] oleCmd, System.IntPtr oleText) + 0x3f bytes

The steps to repeat:

• Debug a program which is the clipboard owner (e. g. "copy" some text from a text box)
• Halt the program in the debugger
• Press the right mouse button in VS to get the context menu.

Do you think you also could provide a bugfix?

Or do you think that the root cause needs to be fixed in VS itself?

Thanks for your efforts!

AnkhSVN now contains a real fix for the problem:
https://ctf.open.collab.net/in...
This fix might also be applicable to ClipBoardDiff.