A multiple-core, multithreaded processor including a flexible error steering mechanism. An integrated circuit may include processor cores. Each processor core is associated with a respective number of threads and is configured to issue a first instruction from one of the threads during one execution cycle and a second instruction from another one of the threads during a successive execution cycle. An error processing unit may be coupled to the processor cores and configured to detect an error condition corresponding to a data element external to the processor cores. In response to detecting the error condition, the error processing unit may convey an indication of the error to a selected processor core dependent upon an identifier of the selected core. The error indication may also include an identifier of a selected thread executable on the selected processor core. The identifiers of the selected core and the selected thread may be programmable.