Bug 527697 - Size of parameter pack where arguments themselves contain a pack

Change-Id: I850eaf74a3fb3ec4b160aedc3f594ff0d0edf31a

2 files changed, 28 insertions, 1 deletions

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 c26b40da2c0..24de5150d1a 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
@@ -9035,6 +9035,24 @@ public class AST2TemplateTests extends AST2CPPTestBase {
 	public void testDependentPackExpansionInFunctionType_526684() throws Exception {
 		parseAndCheckBindings();
 	}
+	
+	//	template <int> struct __make;
+	//	template <> struct __make<2> { typedef int type; };
+	//
+	//	template <typename... T>
+	//	using type_pack_element = typename __make<sizeof...(T)>::type;
+	//
+	//	template <typename... T>
+	//	struct tuple_element {
+	//	    typedef type_pack_element<T...> type;
+	//	};
+	//
+	//	typedef tuple_element<int, int>::type Waldo;
+	public void testSizeofParameterPack_527697() throws Exception {
+		BindingAssertionHelper helper = getAssertionHelper();
+		ITypedef waldo = helper.assertNonProblem("Waldo");
+		assertSameType(CommonCPPTypes.int_, waldo);
+	}
 
 	//	template <typename T>
 	//	struct A {};
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 5ae163e256a..12346969e22 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
@@ -1221,8 +1221,17 @@ public class CPPTemplates {
 	static int determinePackSize(ICPPTemplateParameter tpar, ICPPTemplateParameterMap tpMap) {
 		if (tpar.isParameterPack()) {
 			ICPPTemplateArgument[] args= tpMap.getPackExpansion(tpar);
-			if (args != null)
+			if (args != null) {
+				// The arguments could be dependent, so they could themselves
+				// contain pack expansions.
+				for (ICPPTemplateArgument arg : args) {
+					if (arg.isPackExpansion()) {
+						return PACK_SIZE_DEFER;
+					}
+				}
+				
 				return args.length;
+			}
 			return PACK_SIZE_DEFER;
 		}
 		return PACK_SIZE_NOT_FOUND;