In a large, heavy pot, warm olive oil over medium-high heat. Add sausage and garlic; sauté, stirring, until sausage has browned, about 5 minutes.
Stir in eggplant, olives, tomatoes, sugar and crushed red pepper. Season with salt and pepper. Using a spatula, break tomatoes into chunks. Bring sauce to a boil, reduce heat and simmer until eggplant is soft, 30 to 40 minutes. Serve pasta with sauce.