https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89378
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Created attachment 45960 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45960&action=edit gcc9-pr89378.patch Untested (quite obvious) fix, though I don't really have a way to test this. If you could test this, I can submit it to gcc-patches. In RTL, a SUBREG of a SUBREG is invalid, and gen_lowpart is a function that takes care of all the folding to get the right single SUBREG.
