https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61135
--- Comment #8 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to lc289dafd7ybme05se from comment #7) > 仮想継承の時もエラーになるみたいですね。 To save some clicking, Google translate said: "It seems to be an error even when the virtual inheritance."