https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68761
--- Comment #5 from David Kredba <nheghathivhistha at gmail dot com> --- (In reply to Jakub Jelinek from comment #4) > Please report that into a separate PR, this one is graphite related, your is > some C++17 C++ FE bug. What is going on is that cp_genericize_r first > converts changes a by-reference RESULT_DECL into INDIRECT_REF of it, and > then (dunno if because of tree sharing or some constexpr stuff) at some > point that IL is passed again to cp_genericize_r again and again performs > the same change, so we in the end have two nested INDIRECT_REFs and the > types don't match any longer. Thank you, opened as PR69001.