I wonder if sigsetjmp shouldn't be also used for Linux, just in case

sigsetjmp() is a POSIX standard. setjmp() is ISO C. So setjmp() provides for greater compatibility, but I would argue that sigsetjmp() should preferably be used in any POSIX compliant system.
(Actually, I would argue to take all these methods out the back and humanely dispose of them, but we're veering off subject)