re PR c++/92869 (C++17 wrongly reports aggregate type as not-aggregate (when explicitly defaulted ctors are added))
PR c++/92869
* class.c (finish_struct): For C++17 and earlier, check
type_has_user_provided_or_explicit_constructor rather than
TYPE_HAS_USER_CONSTRUCTOR whether to set CLASSTYPE_NON_AGGREGATE.
* g++.dg/cpp0x/aggr3.C: New test.
From-SVN: r279241
