https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81997
Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org --- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Reduced testcase: template <typename> void foo (); namespace std { template <class> struct initializer_list { int *b; unsigned long c; int begin (); int m (); }; } template <typename E, typename F> concept bool g = requires(E x) { x (foo <F>); }; template <typename H, typename I> requires g<I, decltype(foo<H>)> I bar (H, H, I); void baz () { auto l = {5}; bar (l.begin (), l.m (), [](auto m) { m; }); } Probably related to PR81918, at least the error is the same, just error recovery different.