VS2008: Unit Testing with Code Coverage doesn't work with /CLR - visual-studio

Question

I'm trying to set up unit testing with code coverage in VS2008, for a C++/CLI DLL which is compiled with /clr (not /clr:safe or /clr:pure - it has to be /clr because it uses MFC).
The unit tests work perfectly but the coverage information only works if I compile with /clr:safe or /clr:pure. For /clr the Code Coverage Results window shows the following message:
Empty results generated: none of the
instrumented binary was used. Look at
test run details for any
instrumentation problems.
I've also tried "going offroad" but when I load the coverage file into VS, it also contains empty results.
Annoyingly I can't find anywhere that specifically says whether Code Coverage works with /CLR, so I just had to try it myself.
If it should work, can anyone see what I'm doing wrong here?
[File]->[New]->[Project]
Select Class Library, enter MyProj as the project name, click OK
Right-click on MyProj project, select [Properties]
Select [Configuration Properties]->[General]
Ensure "Common Language Runtime support" is set to /CLR
Add this code to Class1:
public:
static int calc() { return 69; }
Build solution
[Test]->[New Test]->[Unit Test], click OK, click Create
Add this code to TestMethod1:
Assert::AreEqual(MyProj::Class1::calc(), 69);
Right-click on TestProject1 project, select [References]
Click "Add New Reference"
Select MyProj in the "Projects" tab, click OK, click OK again
[Test]->[Edit Test Run Configuration]->[Local Test Run]
Select [Code Coverage]
Check MyProj.dll, click Apply, click Close
[Test]->[Run]->[All Tests in Solution]
The Test Results window shows TestMethod1 has passed.
The Code Coverage Results window shows the following message:
Empty results generated: none of the
instrumented binary was used. Look at
test run details for any
instrumentation problems.
Right-click on MyProj project, select [Properties]
Select [Configuration Properties]->[General]
Change "Common Language Runtime support" to /CLR:SAFE or /CLR:PURE, click OK
Build solution
[Test]->[Run]->[All Tests In Solution]
The Test Results window shows TestMethod1 has passed.
The Code Coverage Results window now shows correct coverage information.

Answer 1

Based on http://msdn.microsoft.com/en-us/library/ms182534.aspx
1-project must be in debug
2.-in the project properties you must select x 86 platform.
3 Unregister the project being tested in the GAC.

Answer 2

Yeh, I think it all has to be in CLR:Safe project to work. I don't fully understand why, but I'm in the same boat as you.