[Bug c++/51633] [c++0x] [4.6/4.7 Regression] ICE with invalid constexpr constructor

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51633

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-11 13:52:11 UTC ---
The testcase is valid because A's implicitly-declared default constructor is
constexpr.  We just need to fix build_constexpr_member_initializers to deal
with the trees that we get for B().