Bug 542448 - Return ProblemBindings in list initialization

- Return ProblemBinding if conversion from init list failed
- In conversion: don't allow implicit conversion with explicit ctor

Change-Id: I3145b89df778a035ced9999aff4d8a4164eac17f
Signed-off-by: Hannes Vogt <hannes@havogt.de>

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

@@ -148,6 +148,7 @@ import org.eclipse.cdt.core.parser.util.CharArrayUtils;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPASTNameBase;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPBasicType;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPClassType;
+import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPConstructor;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPFunctionType;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPMethod;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPPointerType;
@@ -4225,13 +4226,15 @@ public class AST2CPPTests extends AST2CPPTestBase {
 	}
 
 	// class X {
-	//    X(const X &);
+	// public:
+	//   X(const X &);
 	// };
 	// class Y {
-	//    operator X ();
+	// public:
+	//    operator X();
 	// };
 	// Y y;
-	// X x = new X(y);
+	// X* x = new X(y);
 	public void testBug90654a() throws Exception {
 		IASTTranslationUnit tu = parse(getAboveComment(), CPP);
 		NameCollector col = new NameCollector(true);
@@ -12777,4 +12780,58 @@ public class AST2CPPTests extends AST2CPPTestBase {
 	public void testElabSpecInTrailingReturn_535777() throws Exception {
 		parseAndCheckBindings();
 	}
+
+	//	struct type {
+	//		type(int,int){};
+	//	};
+	//
+	//	int main() {
+	//		type a0(1,2);
+	//		type a1{1,2};
+	//		type a2 = {1,2};
+	//		type a3(1,2,3);
+	//		type a4{1,2,3};
+	//		type a5 = {1,2,3};
+	//	}
+	public void testInitListConstructor_542448() throws Exception {
+		BindingAssertionHelper bh = getAssertionHelper();
+		bh.assertImplicitName("a0", 2, CPPConstructor.class);
+		bh.assertImplicitName("a1", 2, CPPConstructor.class);
+		bh.assertImplicitName("a2", 2, CPPConstructor.class);
+
+		bh.assertImplicitName("a3", 2, IProblemBinding.class);
+		bh.assertImplicitName("a4", 2, IProblemBinding.class);
+		bh.assertImplicitName("a5", 2, IProblemBinding.class);
+	}
+
+	//	struct type {
+	//		explicit type(int,int){};
+	//	};
+	//
+	//	int main() {
+	//		type a0(1,2); // ok
+	//		type a1{1,2}; // ok
+	//		type a2 = {1,2}; // error: using explict ctor
+	//	}
+	public void testInitListConstructorWithExplicit_542448() throws Exception {
+		BindingAssertionHelper bh = getAssertionHelper();
+		bh.assertImplicitName("a0", 2, CPPConstructor.class);
+		bh.assertImplicitName("a1", 2, CPPConstructor.class);
+		bh.assertImplicitName("a2", 2, IProblemBinding.class);
+	}
+
+	// struct type {
+	//     explicit type(int,int);
+	//     type(float,float);
+	// };
+	// int main() {
+	//     type a0 = {1,2};
+	// }
+	public void testInitListConstructorWithExplicit2_542448() throws Exception {
+		BindingAssertionHelper bh = getAssertionHelper();
+		// ill-formed, because overload resolution
+		// prefers the (int,int) constructor
+		// which is explicit
+		bh.assertImplicitName("a0", 2, IProblemBinding.class);
+	}
 }

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

@@ -3738,6 +3738,9 @@ public class CPPSemantics {
 						if (f instanceof ICPPConstructor)
 							return f;
 						// If a conversion is used, the constructor is elided.
+					} else {
+						return new ProblemBinding(null, typeId, ISemanticProblem.BINDING_NOT_FOUND,
+								type.getConstructors());
 					}
 				}
 			} else if (initializer instanceof ICPPASTInitializerList) {
@@ -3749,6 +3752,9 @@ public class CPPSemantics {
 						ICPPFunction f = c.getUserDefinedConversion();
 						if (f instanceof ICPPConstructor)
 							return f;
+					} else {
+						return new ProblemBinding(null, typeId, ISemanticProblem.BINDING_NOT_FOUND,
+								type.getConstructors());
 					}
 				}
 			} else if (initializer instanceof ICPPASTConstructorInitializer) {

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

@@ -728,11 +728,16 @@ public class Conversions {
 				}
 			}
 		}
+
 		final IBinding result = CPPSemantics.resolveFunction(data, filteredConstructors, true, false);
 		final Cost c;
 		if (result instanceof ICPPMethod) {
-			c = new Cost(arg.getType(), t, Rank.IDENTITY);
+			if (!isDirect && ((ICPPMethod) result).isExplicit()) {
-			c.setUserDefinedConversion((ICPPMethod) result);
+				c = Cost.NO_CONVERSION;
+			} else {
+				c = new Cost(arg.getType(), t, Rank.IDENTITY);
+				c.setUserDefinedConversion((ICPPMethod) result);
+			}
 		} else if (result instanceof IProblemBinding
 				&& ((IProblemBinding) result).getID() == IProblemBinding.SEMANTIC_AMBIGUOUS_LOOKUP) {
 			c = new Cost(arg.getType(), t, Rank.USER_DEFINED_CONVERSION);