that actually refer to the same underlying type, it is not an
ambiguity; add uniquing support based on the canonical type of type
declarations. Fixes <rdar://problem/8296180>.
llvm-svn: 110806
are a couple of O(n^2) operations in this, some analogous to the usual O(n^2)
redeclaration problem and some not. In particular, retroactively removing
shadow declarations when they're hidden by later decls is pretty unfortunate.
I'm not yet convinced it's worse than the alternative, though.
llvm-svn: 91045