http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55993
--- Comment #7 from Marc Glisse <glisse at gcc dot gnu.org> 2013-01-15 19:34:17
UTC ---
struct A {};
struct B:A {};
struct C:A {};
struct D:B,C {};
constexpr D d;
constexpr const C& e=d; // OK
constexpr auto f=static_cast<const C&>(d); // FAIL
constexpr auto g=static_cast<const B&>(d); // FAIL different
Interesting mix of error messages:
e.cc:8:41: error: accessing value of 'd' through a 'const C' glvalue in a
constant expression
constexpr auto f=static_cast<const C&>(d); // FAIL
^
e.cc:9:41: error: the value of 'd' is not usable in a constant expression
constexpr auto g=static_cast<const B&>(d); // FAIL different
^
e.cc:6:13: note: 'd' used in its own initializer
constexpr D d;
^
