Propagate the new callback to our InterpreterCallbacks interface.

include/cling/Interpreter/InterpreterCallbacks.h

@@ -21,6 +21,7 @@ namespace clang {
   class LookupResult;
   class NamedDecl;
   class Scope;
+  class TagDecl;
   class Type;
 }
 
@@ -110,8 +111,10 @@ namespace cling {
     ///
     /// \returns true if lookup result is found and should be used.
     ///
+    // FIXME: Find a way to merge the three of them.
     virtual bool LookupObject(clang::LookupResult&, clang::Scope*);
     virtual bool LookupObject(const clang::DeclContext*, clang::DeclarationName);
+    virtual bool LookupObject(clang::TagDecl*);
 
     ///\brief This callback is invoked whenever interpreter has committed new
     /// portion of declarations.
@@ -177,6 +180,9 @@ namespace cling {
       bool LookupObject(const clang::DeclContext*, clang::DeclarationName) {
         return false;
       }
+      bool LookupObject(clang::TagDecl* Tag) {
+        return false;
+      }
       bool ShouldResolveAtRuntime(clang::LookupResult& R, clang::Scope* S);
     };
   } // end test

lib/Interpreter/InterpreterCallbacks.cpp

@@ -101,6 +101,11 @@ namespace cling {
       return false;
     }
 
+    virtual void CompleteType(TagDecl* Tag) {
+      if (m_Callbacks)
+        m_Callbacks->LookupObject(Tag);
+    }
+
     void UpdateWithNewDeclsFwd(const DeclContext *DC, DeclarationName Name, 
                                llvm::ArrayRef<NamedDecl*> Decls) {
       SetExternalVisibleDeclsForName(DC, Name, Decls);
@@ -183,6 +188,11 @@ namespace cling {
     return false;
   }
 
+  bool InterpreterCallbacks::LookupObject(TagDecl*) {
+    // Default implementation is no op.
+    return false;
+  }
+
   void InterpreterCallbacks::UpdateWithNewDecls(const DeclContext *DC, 
                                                 DeclarationName Name, 
                                              llvm::ArrayRef<NamedDecl*> Decls) {