Fix PR20334: invalid assertion while diagnosing list initialization failure

https://llvm.org/bugs/show_bug.cgi?id=20334

Unfortunately, clang currently checks for a certain brokenness of implementations of std::initializer_list in CodeGen (void 
AggExprEmitter::VisitCXXStdInitializerListExpr), not in SemaInit.  Until that is fixed, make sure we don't let broken attempts that are aggregates leak through into sema, which allows maintenance of expected invariants, and avoids triggering an assertion.



 

llvm-svn: 254889