Bug 399039 - Error involving variadic non-type template parameter

Change-Id: I61b19e1fc5aac9372ad756c1e33e412f4bee86e2

Reviewed-on: https://git.eclipse.org/r/9943
Reviewed-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>
IP-Clean: Sergey Prigogin <eclipse.sprigogin@gmail.com>
Tested-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java

@@ -7069,6 +7069,33 @@ public class AST2TemplateTests extends AST2TestBase {
 		parseAndCheckBindings();
 	}
 
+	//	template <bool...>
+	//	struct ice_or {
+	//	    static const bool value = false;
+	//	};
+	//	template <typename T>
+	//	struct is_foo {
+	//	    static const bool value = false;
+	//	};
+	//	template <typename... Args>
+	//	struct contains_foo {
+	//	    static const bool value = ice_or<is_foo<Args>::value...>::value;
+	//	};
+	//	template <bool> 
+	//	struct meta;
+	//	struct S { void bar(); };
+	//	template <> 
+	//	struct meta<false> {
+	//	    typedef S type;
+	//	};
+	//	int main() {
+	//	    meta<contains_foo<>::value>::type t;
+	//	    t.bar();
+	//	}
+	public void testVariadicNonTypeTemplateParameter_399039() throws Exception {
+		parseAndCheckBindings();
+	}
+
 	//	template <typename...>
 	//	struct common_type;
 	//	template <typename T>

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/ICPPEvaluation.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2012 Wind River Systems, Inc. and others.
+ * Copyright (c) 2012, 2013 Wind River Systems, Inc. and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -8,6 +8,7 @@
  * Contributors:
  *     Markus Schorn - initial API and implementation
  *     Sergey Prigogin (Google)
+ *     Nathan Ridge
  *******************************************************************************/
 package org.eclipse.cdt.internal.core.dom.parser.cpp;
 
@@ -84,8 +85,16 @@ public interface ICPPEvaluation extends ISerializableEvaluation {
 			IASTNode point);
 
 	/**
-	 * Determines size of the template parameter pack.
+	 * Searches the evaluation for a usage of a template parameter which is a parameter pack,
+	 * and returns the number of arguments bound to that parameter pack in the given
+	 * template parameter map.
 	 *
+	 * Can also return one of the special values CPPTemplates.PACK_SIZE_DEFER,
+	 * CPPTemplates.PACK_SIZE_FAIL, and CPPTemplates.PACK_SIZE_NOT_FOUND. See their
+	 * declarations for their meanings.
+	 *
+	 * See also CPPTemplates.determinePackSize().
+	 * 
 	 * @noreference This method is not intended to be referenced by clients. 
 	 */
 	int determinePackSize(ICPPTemplateParameterMap tpMap);

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java

@@ -162,9 +162,23 @@ import org.eclipse.cdt.internal.core.dom.parser.cpp.semantics.Conversions.UDCMod
  * type instantiation.
  */
 public class CPPTemplates {
+	// The three constants below are used as special return values for the various overloads
+	// of CPPTemplates.determinePackSize() and for ICPPEvaluation.determinePackSize(), which
+	// search a type, template argument, or value for a usage of a template parameter pack
+	// and return the number of arguments bound to that parameter pack in an 
+	// ICPPTemplateParameterMap.
+
+	// Used to indicate that the parameter pack is not bound to any arguments in the
+	// template parameter map. Computation of the pack size needs to be deferred until
+	// arguments for it become available.
 	static final int PACK_SIZE_DEFER = -1;
+
+	// Used to indicate that two different packs with different sizes were found.
 	static final int PACK_SIZE_FAIL = -2;
+
+	// Used to indicate that no template parameter packs were found.
 	static final int PACK_SIZE_NOT_FOUND = Integer.MAX_VALUE;
+
 	static enum TypeSelection { PARAMETERS, RETURN_TYPE, PARAMETERS_AND_RETURN_TYPE }
 
 	/**

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalID.java

@@ -360,8 +360,13 @@ public class EvalID extends CPPEvaluation {
 	@Override
 	public int determinePackSize(ICPPTemplateParameterMap tpMap) {
 		int r = fFieldOwner != null ? fFieldOwner.determinePackSize(tpMap) : CPPTemplates.PACK_SIZE_NOT_FOUND;
-		for (ICPPTemplateArgument arg : fTemplateArgs) {
-			r = CPPTemplates.combinePackSize(r, CPPTemplates.determinePackSize(arg, tpMap));
+		if (fNameOwner instanceof ICPPUnknownBinding) {
+			r = CPPTemplates.combinePackSize(r, CPPTemplates.determinePackSize((ICPPUnknownBinding) fNameOwner, tpMap));
+		}
+		if (fTemplateArgs != null) {
+			for (ICPPTemplateArgument arg : fTemplateArgs) {
+				r = CPPTemplates.combinePackSize(r, CPPTemplates.determinePackSize(arg, tpMap));
+			}
 		}
 		return r;
 	}