Do you have any idea about this topic?
Design a set of simple test programs to determine the type compatibility rules of a C compiler.
First you need to ask yourself "what are the type rules?" Once you know the answer to that question you can test your compiler out to see if it complies with those rules. I'm not sure myself what is meant by that question, the only way for you to find out is to read your textbook or review the lecture notes from your classes.
Here is an article that most likely describes type compatability rules.