https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96781
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- gcc (Ubuntu 20200418-1ubuntu1) 10.0.1 20200418 (experimental) is a quite old prerelease. Please update and re-try. We also need preprocessed source as a reproducer.
