https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65020
--- Comment #1 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> --- Do you have 770c9167327b3c20b718dae5062d57a052316a78 / 220316 applied? That patch is not a complete fix (see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935), but it fixes the bootstrap problem.