https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69454
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- I need additional -march=x86-64 to trigger this. I'd say either we have to pessimistically assume what the STV pass might be doing already during expansion, or the STV pass would need to perform parts of what expand_stack_alignment is doing (basically check if what the STV pass created causes any differences in decision during expand_stack_alignment, and if yes, tweak things so that the end result looks as if those decisions were done already during the expansion (STV is pre-RA pass, so maybe it still could work), or maybe easiest fix is for now disable TARGET_STV if preferred_stack_boundary is smaller than 4.
