1. A method for performing an error detection in a cache memory for storing data, the access to the data stored in the cache memory taking place by addresses assigned thereto, comprising: for the addresses assigned to the stored data, generating and storing in the cache memory at least one first test signature made up of at least one first signature bit; storing a valid-invalid bit at least in duplicate in the cache memory; to a group of data and appertaining first test signatures, assigning in each case a first line index in the cache memory; comparing the first line index to a second line index applied at the cache memory; and retrieving the first line index from the cache memory by line decoding.