Why do you think you need the “else: ??? What do I do here?” case?
Until you added the 2nd test and the 2nd else case, there is no scenario under which both paths of an if/else would fail to execute due to a bit flip of the test variable, because with ‘if (boolean_condition) {} else {}’ there is only 1 conditional test. A bit flip could have caused the wrong branch to execute, but it could not have skipped both branches. A bit flip could change the jump instruction to something else, but in that case your imagined else case still wouldn’t help.
> this is, at best, a very very partial solution
FWIW, the author said this, and fairly succinctly, saying this TRUE=7 thing is “of course foolish as such a 1 bit hardware error would "trash" pretty much any system”. He was only having a bit of fun that cost nothing, and nowhere suggested this is a solution to cosmic rays or other data errors.
Until you added the 2nd test and the 2nd else case, there is no scenario under which both paths of an if/else would fail to execute due to a bit flip of the test variable, because with ‘if (boolean_condition) {} else {}’ there is only 1 conditional test. A bit flip could have caused the wrong branch to execute, but it could not have skipped both branches. A bit flip could change the jump instruction to something else, but in that case your imagined else case still wouldn’t help.
> this is, at best, a very very partial solution
FWIW, the author said this, and fairly succinctly, saying this TRUE=7 thing is “of course foolish as such a 1 bit hardware error would "trash" pretty much any system”. He was only having a bit of fun that cost nothing, and nowhere suggested this is a solution to cosmic rays or other data errors.