I'd like to see a variation of this contest where a "typical", valid source code is given as part of the rules, and the objective is to change the code as little as possible to produce the highest amount of compilation errors. For example it could be measured the ratio between the output of the compiler and the edit distance with the reference code.

It would be more representative of all those WTF moments when you have some code that compiles perfectly fine, change a line and suddenly GCC decides to throw up thousands of meaningless messages :)