https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61723
--- Comment #5 from Paul Pluzhnikov <ppluzhnikov at google dot com> --- (In reply to Paolo Carlini from comment #1) > I find this testcase rather weird It's the result of creduce over a preprocessed original. > std::initializer_list isn't a random user type In the non-reduced test (which is 15MB in size), it's the full type. > OK, now GCC will reject the definition of std::initializer_list rather than > ICE. I'll check whether original test still ICEs, and re-reduce if it still does.