diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
index 75a6432cfe8..2008a13a293 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
@@ -7560,7 +7560,7 @@ public class AST2TemplateTests extends AST2TestBase {
 	public void testSfinaeInNewExpressionWithDeletedConstructor_430230() throws Exception {
 		parseAndCheckBindings();
 	}
-
+	
 	//	template <typename>
 	//	struct M {
 	//	    template <typename... Args>
@@ -7869,6 +7869,41 @@ public class AST2TemplateTests extends AST2TestBase {
     public void testVariadicTemplatesAndFunctionObjects_401479() throws Exception {
     	parseAndCheckBindings();
     }
+    
+	//	template<typename _Tp>
+	//	_Tp declval() noexcept;
+	//
+	//	template<typename _From>
+	//	struct is_convertible {};
+	//
+	//	template<typename _Signature>
+	//	class function;
+	//
+	//	template<typename _Res, typename... _ArgTypes>
+	//	class function<_Res(_ArgTypes...)> {
+	//	  template<typename _Functor>
+	//	  using _Invoke = decltype(declval<_Functor&>()(declval<_ArgTypes>()...));
+	//
+	//	public:
+	//	  template<typename _Functor, typename = typename is_convertible<_Invoke<_Functor>>::type>
+	//	  function(_Functor);
+	//	};
+	//
+	//	class A {};
+	//
+	//	struct B {
+	//	  B(const char* s);
+	//	};
+	//
+	//	template <class T> void waldo(const B& response);
+	//	template <class T> void waldo(function<T()> generator);
+	//
+	//	void test() {
+	//	    waldo<A>("");  // problem on waldo
+	//	}
+	public void testPackExpansionInNestedTemplate_459844() throws Exception {
+		parseAndCheckBindings();
+	}
 
 	// struct S {
 	//     void kind();
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPDependentEvaluation.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPDependentEvaluation.java
index 967ba84a635..b5138240a70 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPDependentEvaluation.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPDependentEvaluation.java
@@ -115,11 +115,11 @@ public abstract class CPPDependentEvaluation extends CPPEvaluation {
 			ICPPEvaluation origEval = subexpressions[i];
 			ICPPEvaluation newEval;
 			if (origEval instanceof EvalParameterPack) {
-				origEval = ((EvalParameterPack) origEval).getExpansionPattern();
-				if (origEval == null) {
+				ICPPEvaluation pattern = ((EvalParameterPack) origEval).getExpansionPattern();
+				if (pattern == null) {
 					newEval = EvalFixed.INCOMPLETE;
 				} else {
-					int packSize = origEval.determinePackSize(tpMap);
+					int packSize = pattern.determinePackSize(tpMap);
 					if (packSize == CPPTemplates.PACK_SIZE_FAIL || packSize == CPPTemplates.PACK_SIZE_NOT_FOUND) {
 						newEval = EvalFixed.INCOMPLETE;
 					} else if (packSize == CPPTemplates.PACK_SIZE_DEFER) {
@@ -129,7 +129,7 @@ public abstract class CPPDependentEvaluation extends CPPEvaluation {
 						ICPPEvaluation[] newResult = new ICPPEvaluation[subexpressions.length + resultShift + shift];
 						System.arraycopy(result, 0, newResult, 0, i + resultShift);
 						for (int j = 0; j < packSize; ++j) {
-							newEval = origEval.instantiate(tpMap, j, within, maxdepth, point);
+							newEval = pattern.instantiate(tpMap, j, within, maxdepth, point);
 							newResult[i + resultShift + j] = newEval;
 						}
 						result = newResult;
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
index f4e45332690..85ff8210ddd 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
@@ -1214,9 +1214,8 @@ public class CPPTemplates {
 			ICPPTemplateArgument origArg = args[i];
 			ICPPTemplateArgument newArg;
 			if (origArg.isPackExpansion()) {
-				ICPPTemplateArgument unexpanded= origArg;
-				origArg= origArg.getExpansionPattern();
-				int packSize= determinePackSize(origArg, tpMap);
+				ICPPTemplateArgument pattern= origArg.getExpansionPattern();
+				int packSize= determinePackSize(pattern, tpMap);
 				if (packSize == PACK_SIZE_FAIL || packSize == PACK_SIZE_NOT_FOUND) {
 					throw new DOMException(new ProblemBinding(point, IProblemBinding.SEMANTIC_INVALID_TEMPLATE_ARGUMENTS, null));
 				} else if (packSize == PACK_SIZE_DEFER) {
@@ -1226,11 +1225,11 @@ public class CPPTemplates {
 					ICPPTemplateArgument[] newResult= new ICPPTemplateArgument[args.length + resultShift + shift];
 					System.arraycopy(result, 0, newResult, 0, i + resultShift);
 					for (int j= 0; j < packSize; j++) {
-						newArg = instantiateArgument(origArg, tpMap, j, within, point);
+						newArg = instantiateArgument(pattern, tpMap, j, within, point);
 						if (!isValidArgument(newArg)) {
 							if (strict)
 								return null;
-							result[i + resultShift] = unexpanded;
+							result[i + resultShift] = origArg;
 							newResult = result;
 							shift = 0;
 							break;