The debugger component of Visual Studio 2012 is not able to attach to or start one of our own x32 apps written in MS VC++: When the debugger tries to start our app, Visual Studio crashes immediately, before the very first statement of our app even runs.
Our app itself currently runs without problems on Windows XP through Windows 8. VS2005, VS2008 and VS2010 all can be used to debug our app without any problems.
By debugging VS2012 itself with VS2010 (as far as that is possible for me as an outsider) I saw that the program runs into an internal consistency check when trying to free a heap: The heap is considered "corrupted", and devenv.exe terminates. Switching off DEP that seems to help in some such cases does not change anything, neither does running devenv.exe with /SafeMode switch.
I have described the problem and my own investigations so far with many details here: