When selling your home, you as the seller, as well as your broker (if you have one), are responsible for disclosing any known issues that could materially affect the value of the property. More specifically, disclosure must include items which you as the homeowner have personal knowledge but might not be obvious to the casual observer. A cracked foundation would be one example.
When dealing with the sale of your home, you will usually be required to provide a Seller Disclosure Statement. This statement identifies the current condition and history of all physical aspects of your house.