diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTAmbiguousTemplateArgument.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTAmbiguousTemplateArgument.java
index 9d6d73f36de..7984a68f3b9 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTAmbiguousTemplateArgument.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTAmbiguousTemplateArgument.java
@@ -85,7 +85,21 @@ public class CPPASTAmbiguousTemplateArgument extends ASTAmbiguousNode implements
 
 
 	public IASTNode copy() {
-		throw new UnsupportedOperationException();
+		
+		int sizeOfNodes = fNodes.size();
+		IASTNode[] copyNodes = new IASTNode[sizeOfNodes];
+		int arrayIndex = 0;
+		for(IASTNode node : fNodes) {
+			if(node!=null){
+				copyNodes[arrayIndex]=node.copy();
+			}else{
+				copyNodes[arrayIndex]=null;
+			}
+			arrayIndex++;
+		}
+		
+		ICPPASTAmbiguousTemplateArgument ambiguityNode = new CPPASTAmbiguousTemplateArgument(copyNodes);
+		return ambiguityNode;
 	}
 	
 	@Override
diff --git a/lrparser/org.eclipse.cdt.core.lrparser/src/org/eclipse/cdt/core/dom/lrparser/action/cpp/CPPBuildASTParserAction.java b/lrparser/org.eclipse.cdt.core.lrparser/src/org/eclipse/cdt/core/dom/lrparser/action/cpp/CPPBuildASTParserAction.java
index 99a1629a7f4..a7ca0726c84 100644
--- a/lrparser/org.eclipse.cdt.core.lrparser/src/org/eclipse/cdt/core/dom/lrparser/action/cpp/CPPBuildASTParserAction.java
+++ b/lrparser/org.eclipse.cdt.core.lrparser/src/org/eclipse/cdt/core/dom/lrparser/action/cpp/CPPBuildASTParserAction.java
@@ -478,16 +478,7 @@ public class CPPBuildASTParserAction extends BuildASTParserAction {
 		IASTExpression expr = (IASTExpression) astStack.peek();
 		
 		if(expr instanceof IASTIdExpression) {
-			IASTName orgName =((IASTIdExpression)expr).getName();
-			IASTName name = null;
-			try{
-			 name = orgName.copy();
-			 //if there is node throws UnsupportedOperationException in copy, just use the original node
-			} catch(UnsupportedOperationException ue){
-				name = orgName;
-			}
-			
-			ParserUtil.setOffsetAndLength(name, expr);
+			IASTName name = ((IASTIdExpression)expr).getName().copy();
 			
 			IASTNamedTypeSpecifier declSpec = nodeFactory.newTypedefNameSpecifier(name);
 			ParserUtil.setOffsetAndLength(declSpec, name);