--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 39798
One of the problems is that for TARGET_THREAD_SSP_OFFSET targets we completely
wastefully create a MEM we don't really need and then ignore it. This untested
patch attempts to avoid that.
The more important bug is somewhere in the rs6000 backend, that the useless
MEMs at -O0 confuse the backend enough that it contains (useless) .LCTOC0
reference/load without corresponding definition of .LCTOC0. I'll leave this
part to the rs6000 maintainers.