Merge #1700

1700: Merge upstream, last commit before GCC/Rust upstreaming r=CohenArthur a=tschwinge

Co-authored-by: Eric Botcazou <ebotcazou@adacore.com>
Co-authored-by: Richard Biener <rguenther@suse.de>
Co-authored-by: Patrick Palka <ppalka@redhat.com>
Co-authored-by: Jonathan Wakely <jwakely@redhat.com>
Co-authored-by: Harald Anlauf <anlauf@gmx.de>
Co-authored-by: Ian Lance Taylor <iant@golang.org>
Co-authored-by: GCC Administrator <gccadmin@gcc.gnu.org>
Co-authored-by: David Malcolm <dmalcolm@redhat.com>
Co-authored-by: Lulu Cheng <chenglulu@loongson.cn>
Co-authored-by: Alexandre Oliva <oliva@adacore.com>
Co-authored-by: Paul-Antoine Arras <pa@codesourcery.com>
Co-authored-by: Tobias Burnus <tobias@codesourcery.com>
Co-authored-by: Jakub Jelinek <jakub@redhat.com>
Co-authored-by: Martin Liska <mliska@suse.cz>
Co-authored-by: Iskander Shakirzyanov <iskander@ispras.ru>
Co-authored-by: Iain Buclaw <ibuclaw@gdcproject.org>
Co-authored-by: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Co-authored-by: John David Anglin <danglin@gcc.gnu.org>