Why can't I debug into my C++ code on Xcode 4?

My Xcode 4 project has bee开发者_JS百科n working well, but from someday I can't debug into my C++ codes in a cpp file.

When I set a break point at a certain location in the C++ code, the process stops where I want to stop, and I can control the process with 'step over' or 'continue' buttons. However, the debugger does not show any highlights on the location and I cannot access any information. In the left pane, the navigator of Xcode 4, some threads numbers are shown, but they are useless.

A message appears in the console output window :

"Warning: the current language does not match this frame" 

or

"Current language:  auto; currently c++ "

Debugging on Objective C/C++ code works well, though.

What should I do to debug into my C++ codes ???

---

Did you try reinstalling the files? Debugging c++ code on XCode 4.0 works fine for me...