https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82021
--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> --- Did you try with -std=c++1z? (if that solves your issue, this is a DUP, it should be enabled in all mode, but it isn't yet)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82021
--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> --- Did you try with -std=c++1z? (if that solves your issue, this is a DUP, it should be enabled in all mode, but it isn't yet)