Uncorrectable memory errors in pipelined central processing units. A processor core may be connected to a memory system and it may include a processor cache. In response to determining an uncorrectable error in data stored in the memory system, the address of a memory location of the uncorrectable error is stored in an address buffer and a recovery procedure is performed for the processor core. When fetching data from a memory location and if it is determined that the address of this memory location is stored in the address buffer, the content of a cache line related to the address is moved into a quarantine buffer of the processor core. When detecting an error in the data of the moved cache line, a repair procedure for the data of this address is triggered.