https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115579
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Zhendong Su from comment #3) > Perhaps the same or a related issue. It reproduces for -O{s,2,3}. It is the same due to -fno-tree-ch . -Os has a very restrictive version of that.