Bug 335387: Overload resolution and conversion on implied object.

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

@@ -9345,4 +9345,21 @@ public class AST2CPPTests extends AST2BaseTest {
 	public void testOverloadedCommaOpWithConstClassRef_334955() throws Exception {
 		parseAndCheckBindings();
 	}
+	
+	//	struct OK {int ok;};
+	//	struct NOK {};
+	//
+	//	template<typename T> struct bos {
+	//	  NOK operator<<(const void*);
+	//	};
+	//	template <typename T> struct os : bos<T> {};
+	//	OK operator<<(bos<char>&, const char*);
+	//
+	//	void test() {
+	//	  os<char> ss;
+	//	  (ss << "").ok;
+	//	}
+	public void testOverloadedOperatorWithInheritanceDistance_335387() throws Exception {
+		parseAndCheckBindings();
+	}
 }

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

@@ -2560,13 +2560,17 @@ public class CPPSemantics {
 					(((ICPPMethod) fn).isDestructor() || ASTInternal.isStatic(fn, false))) {
 			    // 13.3.1-4 for static member functions, the implicit object parameter always matches, no cost
 			    cost = new Cost(impliedObjectType, implicitParameterType, Rank.IDENTITY);
+			    cost.setImpliedObject();
 			} else if (impliedObjectType == null) {
 				return null;
 			} else if (impliedObjectType.isSameType(implicitParameterType)) {
 				cost = new Cost(impliedObjectType, implicitParameterType, Rank.IDENTITY);
+				cost.setImpliedObject();
 			} else {
 				cost = Conversions.checkImplicitConversionSequence(implicitParameterType, impliedObjectType, sourceIsLValue, UDCMode.FORBIDDEN, Context.IMPLICIT_OBJECT);
-			    if (!cost.converts()) {
+				if (cost.converts()) {
+					cost.setImpliedObject();
+				} else {
 				    if (CPPTemplates.isDependentType(implicitParameterType) || CPPTemplates.isDependentType(impliedObjectType)) {
 				    	IType s= getNestedType(impliedObjectType, TDEF|REF|CVTYPE);
 				    	IType t= getNestedType(implicitParameterType, TDEF|REF|CVTYPE);

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

@@ -130,10 +130,6 @@ public class Conversions {
 					// ... and "cv1 T1" is reference-compatible with "cv2 T2" 
 					Cost cost= isReferenceCompatible(cv1T1, cv2T2, isImpliedObject);
 					if (cost != null) {
-						// [13.3.3.1.4-1] direct binding has either identity or conversion rank.					
-						if (cost.getInheritanceDistance() > 0) {
-							cost.setRank(Rank.CONVERSION);
-						} 
 						cost.setReferenceBinding(refBindingType);
 						return cost;
 					} 
@@ -237,7 +233,7 @@ public class Conversions {
 			// 13.3.3.1.7 no temporary object when converting the implicit object parameter
 			if (!isImpliedObject && ctx != Context.REQUIRE_DIRECT_BINDING) {
 				if (isReferenceRelated(T1, T2) < 0 || compareQualifications(cv1T1, cv2T2) >= 0) {
-					Cost cost= nonReferenceConversion(valueCat, cv2T2, T1, udc, false);
+					Cost cost= nonReferenceConversion(valueCat, cv2T2, T1, udc);
 					if (cost.converts()) {
 						cost.setReferenceBinding(refBindingType);
 					}
@@ -248,7 +244,7 @@ public class Conversions {
 		} 
 		
 		// Non-reference binding
-		return nonReferenceConversion(valueCat, exprType, T1, udc, isImpliedObject);
+		return nonReferenceConversion(valueCat, exprType, T1, udc);
 	}
 
 	/**
@@ -301,7 +297,7 @@ public class Conversions {
 	/**
 	 * 8.5-16
 	 */
-	private static Cost nonReferenceConversion(ValueCategory valueCat, IType source, IType target, UDCMode udc, boolean isImpliedObject) throws DOMException {
+	private static Cost nonReferenceConversion(ValueCategory valueCat, IType source, IType target, UDCMode udc) throws DOMException {
 		if (source instanceof InitializerListType) {
 			return listInitializationSequence(((InitializerListType) source), target, udc, false);
 		}
@@ -334,7 +330,7 @@ public class Conversions {
 			return initializationByConversion(valueCat, source, (ICPPClassType) uqSource, target, udc == UDCMode.DEFER);
 		}
 
-		return checkStandardConversionSequence(uqSource, target, isImpliedObject);
+		return checkStandardConversionSequence(uqSource, target);
 	}
 
 	/**
@@ -496,25 +492,24 @@ public class Conversions {
 		if (cmp < 0)
 			return null;
 		
-		// 7.3.3.13 for overload resolution the implicit this pointer is treated as if 
-		// it were a pointer to the derived class
-		if (isImpliedObject) 
-			inheritanceDist= 0;
-
 		Cost cost= new Cost(cv2Source, cv1Target, Rank.IDENTITY);
 		cost.setQualificationAdjustment(cmp);
-		cost.setInheritanceDistance(inheritanceDist);
+		if (inheritanceDist > 0) {
+			cost.setInheritanceDistance(inheritanceDist);
+			cost.setRank(Rank.CONVERSION);
+		}
+
+		if (isImpliedObject) {
+			cost.setImpliedObject();
+		}
 		return cost;
 	}
 	
 	/**
 	 * [4] Standard Conversions
 	 * Computes the cost of using the standard conversion sequence from source to target.
-	 * @param isImplicitThis handles the special case when members of different
-	 *    classes are nominated via using-declarations. In such a situation the derived to
-	 *    base conversion does not cause any costs.
 	 */
-	private static final Cost checkStandardConversionSequence(IType source, IType target, boolean isImplicitThis) {
+	private static final Cost checkStandardConversionSequence(IType source, IType target) {
 		final Cost cost= new Cost(source, target, Rank.IDENTITY);
 		if (lvalue_to_rvalue(cost))
 			return cost;
@@ -522,7 +517,7 @@ public class Conversions {
 		if (promotion(cost))
 			return cost;
 		
-		if (conversion(cost, isImplicitThis)) 
+		if (conversion(cost)) 
 			return cost;
 
 		if (qualificationConversion(cost))
@@ -1016,7 +1011,7 @@ public class Conversions {
 	 * [4.10] Pointer conversions
 	 * [4.11] Pointer to member conversions
 	 */
-	private static final boolean conversion(Cost cost, boolean forImplicitThis){
+	private static final boolean conversion(Cost cost){
 		final IType s = cost.source;
 		final IType t = cost.target;
 
@@ -1084,10 +1079,8 @@ public class Conversions {
 							return true;
 						}
 						if (depth > 0) {
-							if (!forImplicitThis) {
+							cost.setRank(Rank.CONVERSION);
-								cost.setRank(Rank.CONVERSION);
+							cost.setInheritanceDistance(depth);
-								cost.setInheritanceDistance(depth);
-							}
 							CVQualifier cv= getCVQualifier(srcPtr.getType());
 							cost.source= new CPPPointerType(addQualifiers(tgtPtrTgt, cv.isConst(), cv.isVolatile(), cv.isRestrict()));
 						}

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

@@ -89,6 +89,7 @@ public class Cost {
 	private DeferredUDC fDeferredUDC= DeferredUDC.NONE;
 	private int fQualificationAdjustments;
 	private int fInheritanceDistance;
+	private boolean fImpliedObject;
 	private ICPPFunction fUserDefinedConversion;
 	private ReferenceBinding fReferenceBinding;
 
@@ -175,12 +176,25 @@ public class Cost {
 		// cannot compare costs with deferred user defined conversions
 		assert fDeferredUDC == DeferredUDC.NONE && other.fDeferredUDC == DeferredUDC.NONE;
 
-		int cmp= fRank.compareTo(other.fRank);
+		// 7.3.3.13 (using declarations in classes):
+		// for overload resolution the implicit this pointer 
+		// is treated as if it were a pointer to the derived class
+		final boolean ignoreInheritanceDist= fImpliedObject && other.fImpliedObject;
+		Rank rank = fRank;
+		Rank otherRank = other.fRank;
+		if (ignoreInheritanceDist) {
+			if (rank == Rank.CONVERSION)
+				rank= Rank.IDENTITY;
+			if (otherRank == Rank.CONVERSION)
+				otherRank= Rank.IDENTITY;
+		}
+
+		int cmp= rank.compareTo(otherRank);
 		if (cmp != 0) 
 			return cmp;
 		
 		// rank is equal
-		if (fRank == Rank.USER_DEFINED_CONVERSION) {
+		if (rank == Rank.USER_DEFINED_CONVERSION) {
 			// 13.3.3.1.10
 			if (isAmbiguousUDC() || other.isAmbiguousUDC())
 				return 0;
@@ -195,9 +209,11 @@ public class Cost {
 				return cmp;
 		}
 		
-		cmp= fInheritanceDistance - other.fInheritanceDistance;
+		if (!ignoreInheritanceDist) {
-		if (cmp != 0)
+			cmp= fInheritanceDistance - other.fInheritanceDistance;
-			return cmp;
+			if (cmp != 0)
+				return cmp;
+		}
 
 		if (fReferenceBinding == ReferenceBinding.LVALUE_REF) {
 			if (other.fReferenceBinding == ReferenceBinding.RVALUE_REF_BINDS_RVALUE)
@@ -291,4 +307,8 @@ public class Cost {
 	public ICPPFunction getSelectedFunction() {
 		return fSelectedFunction;
 	}
+
+	public void setImpliedObject() {
+		fImpliedObject= true;
+	}
 }