https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71777
--- Comment #2 from Peter Bergner <bergner at gcc dot gnu.org> --- FYI, this is the output of your demo code on my POWER8 LE Ubuntu 16.04 system: bergner@ampere:~$ gcc demo.c bergner@ampere:~$ ./a.out 1 -- 1 2 3 4 6 9 10 11 14 15 16 17 19 20 23 24 25 27 29 31 33 34 36 37