VMT mess

Attached video shows issue of partial rebuilds. Here is the description of performed steps.

1. Open app in xcode and build it
2. Make sure it performs as expected
3. Swap order of virtual methods in the AbstractClass.h
4. Change something in ConcreteClass.cpp to force it's compilation
5. Run app again
6. Observe that main.cpp is not recompiled even tho it includes AbstractClass.h indirectly.
7. Run application and observe that wrong virtual method is called.