When Sema::RequireCompleteType() is given a class template
specialization type that then fails to instantiate, it returns
'true'. On subsequent invocations, it can return false. Make sure that
this difference doesn't change the result of
Sema::CompareReferenceRelationship, which is expected to remain stable
while we're checking an initialization sequence.
llvm-svn: 178088
the base class. If the base class deduction succeeds, use those results. If
it fails, keep using the results from the derived class template deduction.
This prevents an assertion later where the type of deduction failure doesn't
match up with the template deduction info.
llvm-svn: 167550