 +void MultiplexExternalSemaSource::FindFileRegionDecls(FileID File, 
 +                                                      unsigned Offset,
 +                                                      unsigned Length,
-+                                                 SmallVectorImpl<Decl *> &Decls){
++                                                SmallVectorImpl<Decl *> &Decls){
 +  for(size_t i = 0; i < Sources.size(); ++i)
 +    Sources[i]->FindFileRegionDecls(File, Offset, Length, Decls);
 +}

+  Sources.push_back(&source);
+}
+
+//===-----------------------------------------------------------------------===//
+// ExternalASTSource.
+//===-----------------------------------------------------------------------===//
+
+Decl *MultiplexExternalSemaSource::GetExternalDecl(uint32_t ID) {
+  for(size_t i = 0; i < Sources.size(); ++i)

+
+}
+
+//===----------------------------------------------------------------------===//
+// ExternalSemaSource.
+//===----------------------------------------------------------------------===//
+
+
+void MultiplexExternalSemaSource::InitializeSema(Sema &S) {
