As highlighed in this failing compiler test: https://github.com/gem5/gem5/actions/runs/6348223508/job/17389057995 Clang was failing when compiling "build/ALL/gem5.opt" due missing overrides in `PCState`'s "set" function. This was observed in Clang-14 and, stangely, Clang-8. Change-Id: I240c1087e8875fd07630e467e7452c62a5d14d5b