assuming rock-star define as some one who tout all along he is rock star programmer, then not much make a rock-star. But if what you looking at are someone who

assuming rock-star define as some one who tout all along he is rock star programmer, then not much make a rock-star. But if what you looking at are someone who project creative jutsu on programming problem, deliver solution within expected time frame if not earlier and well liked by management and fellow programmer, then what it takes is very clear: 1) sufficient programming knowledge and skill 2) domain knowledge 3) time management 4) good personalities. just, i'm sure that kind of programmer don't like to be called rock-star programmer.