>> serinus has been complaining about the new gcd functions in 13~:
>
> moonjelly, which also runs a bleeding-edge gcc, started to fail the same
> way at about the same time.  Given that none of our code in that area
> has changed, it's hard to think it's anything but a broken compiler.
> Maybe somebody should report that to gcc upstream?
Yes.
I will isolate a small case (hopefully) and do a report over week-end, 
after checking that the latest version is still broken.
-- 
Fabien.