https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82643
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2018-07-06
Ever confirmed|0 |1
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
GCC 6 rejected that code with a more sensible diagnostic:
c.cc:14:30: error: the value of 'f' is not usable in a constant expression
GCC 7 regressed to saying:
c.cc:14:30: error: '__closure' is not a constant expression
Clang and EDG both reject the code, but diagnosing different lines.