Bug 458679 - Ranking list-initialization sequences with user-defined

conversions

Change-Id: Ia976acf656f3431f96880b32fedc575a56c4e86b
Signed-off-by: Nathan Ridge <zeratul976@hotmail.com>

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTests.java

@@ -8778,6 +8778,30 @@ public class AST2CPPTests extends AST2TestBase {
 		helper.assertProblem("waldo({1, 2, 3, 4})", "waldo", IProblemBinding.SEMANTIC_NAME_NOT_FOUND);
 	}
 	
+	//	namespace std {
+	//		template<class E>
+	//		class initializer_list {
+	//		  const E* _array;
+	//		  long unsigned int _len;
+	//
+	//		  initializer_list(const E* array, int len) {}
+	//		};
+	//	}
+	//
+	//	template<typename T>
+	//	struct A {
+	//	  A(std::initializer_list<T> list) {}
+	//	};
+	//
+	//	struct B {
+	//	  int b;
+	//	};
+	//
+	//	A<B> waldo({{0}, {0}});	
+	public void testListInitialization_458679() throws Exception {
+		parseAndCheckImplicitNameBindings();
+	}
+	
 	//	namespace std {
 	//		template<typename T> class initializer_list;
 	//	}

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

@@ -128,14 +128,6 @@ public class AST2TemplateTests extends AST2TestBase {
 		return parseAndCheckBindings(code, CPP);
 	}
 
-	protected IASTTranslationUnit parseAndCheckImplicitNameBindings() throws Exception {
-		IASTTranslationUnit tu = parse(getAboveComment(), CPP, false, true);
-		NameCollector col = new NameCollector(true /* Visit implicit names */);
-		tu.accept(col);
-		assertNoProblemBindings(col);
-		return tu;
-	}
-
 	protected BindingAssertionHelper getAssertionHelper() throws ParserException, IOException {
 		String code= getAboveComment();
 		return new BindingAssertionHelper(code, true);

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TestBase.java

@@ -15,6 +15,8 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.parser.tests.ast2;
 
+import static org.eclipse.cdt.core.parser.ParserLanguage.CPP;
+
 import java.io.IOException;
 import java.lang.reflect.Field;
 import java.util.ArrayList;
@@ -775,6 +777,14 @@ public class AST2TestBase extends BaseTestCase {
 		assertNoProblemBindings(col);
 		return tu;
 	}
+	
+	final protected IASTTranslationUnit parseAndCheckImplicitNameBindings() throws Exception {
+		IASTTranslationUnit tu = parse(getAboveComment(), CPP, false, true);
+		NameCollector col = new NameCollector(true /* Visit implicit names */);
+		tu.accept(col);
+		assertNoProblemBindings(col);
+		return tu;
+	}
 
 	final protected void assertNoProblemBindings(NameCollector col) {
 		for (IASTName n : col.nameList) {

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

@@ -601,6 +601,11 @@ public class Conversions {
 					bestCost.setRank(Rank.NO_MATCH);
 				}
 			}
+			// This cost came from listInitializationSequence() with an std::initializer_list
+			// type as the list initialization target. From the point of view of the caller, 
+			// however, the target is the class type, not std::initializer_list, so update it
+			// accordingly.
+			bestCost.setListInitializationTarget(t);
 			return bestCost;
 		}
 

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

@@ -200,6 +200,35 @@ public class Cost {
 		if (cmp != 0) 
 			return cmp;
 		
+		// [over.ics.rank] p3.3:
+		// List-initialization sequence L1 is a better conversion sequence than
+		// list-initialization sequence L2 if 
+		if (fListInitializationTarget != null && other.fListInitializationTarget != null) {
+			//   - L1 converts to std::initializer_list<X> for some X and L2 does not,
+			//     or if not that,
+			IType initListType = Conversions.getInitListType(fListInitializationTarget);
+			IType otherInitListType = Conversions.getInitListType(other.fListInitializationTarget);
+			if (initListType != null && otherInitListType == null) {
+				return -1;
+			} else if (initListType == null && otherInitListType != null) {
+				return 1;
+			}
+			
+			//   - L1 converts to type "array of N1 T", L2 converts to type "array of
+			//     N2 T", and N1 is smaller than N2
+			if (fListInitializationTarget instanceof IArrayType && other.fListInitializationTarget instanceof IArrayType) {
+				IArrayType arrayType = (IArrayType) fListInitializationTarget;
+				IArrayType otherArrayType = (IArrayType) other.fListInitializationTarget;
+				if (arrayType.getType().isSameType(otherArrayType.getType())) {
+					Long size = arrayType.getSize().numericalValue();
+					Long otherSize = otherArrayType.getSize().numericalValue();
+					if (size != null && otherSize != null) {
+						return size.compareTo(otherSize);
+					}
+				}
+			}
+		}
+		
 		// rank is equal
 		if (rank == Rank.USER_DEFINED_CONVERSION) {
 			// 13.3.3.1.10
@@ -241,35 +270,7 @@ public class Cost {
 			if ((other.fQualificationAdjustments & qdiff) == 0)
 				return 1;
 		}		
-		
+
-		// [over.ics.rank] p3:
-		// List-initialization sequence L1 is a better conversion sequence than
-		// list-initialization sequence L2 if 
-		if (fListInitializationTarget != null && other.fListInitializationTarget != null) {
-			//   - L1 converts to std::initializer_list<X> for some X and L2 does not,
-			//     or if not that,
-			IType initListType = Conversions.getInitListType(fListInitializationTarget);
-			IType otherInitListType = Conversions.getInitListType(other.fListInitializationTarget);
-			if (initListType != null && otherInitListType == null) {
-				return -1;
-			} else if (initListType == null && otherInitListType != null) {
-				return 1;
-			}
-			
-			//   - L1 converts to type "array of N1 T", L2 converts to type "array of
-			//     N2 T", and N1 is smaller than N2
-			if (fListInitializationTarget instanceof IArrayType && other.fListInitializationTarget instanceof IArrayType) {
-				IArrayType arrayType = (IArrayType) fListInitializationTarget;
-				IArrayType otherArrayType = (IArrayType) other.fListInitializationTarget;
-				if (arrayType.getType().isSameType(otherArrayType.getType())) {
-					Long size = arrayType.getSize().numericalValue();
-					Long otherSize = otherArrayType.getSize().numericalValue();
-					if (size != null && otherSize != null) {
-						return size.compareTo(otherSize);
-					}
-				}
-			}
-		}
 		return 0;
 	}