https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66256
--- Comment #9 from David Stone <david at doublewise dot net> --- Sorry, I misread the chain of comments, Jonathan Wakely's comment on gcc correctly rejecting invalid code refers specifically to the decltype example. Please ignore my previous comment, except that it captures the wording from the standard that says that the test case for this bug should work.
