https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107728
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Move over, the functions are not optimized out at -O2 but rather they don't get pulled in glibc building because another function is referenced. Either libgcc should be built with -fdata-sections -ffunction-sections or glibc builds needs to be fixed such that it does not reference the function in the unwinder at -O0. You need to look at the linker map to figure why the object file is being pulled into glibc at -O0 and not at -O2. But it is still a bug in glibc's ld.so really.
