Bug 84144 - [Parser2] GCC: labels as values

Add support for GNU goto label references.

"http://gcc.gnu.org/onlinedocs/gcc-3.3.2/gcc/Labels-as-Values.html#Labels%20as%20Values
GCC extensions to C allow taking the address of labels. These addresses can be used in a goto statement where any expression of type void * is allowed:

foo:
  void* labelPtr = &&foo;
  goto *labelPtr;", comment from Andrew Niefer

Add new classes and necessary changes in existing classes to support the above.
Updated to not change API.

Signed-off-by: Anders Dahlberg <anders.xb.dahlberg@ericsson.com>
Change-Id: Ibb69ce7748f201c15bdf2da05348c157cdd5aaae
Reviewed-on: https://git.eclipse.org/r/29574
Tested-by: Hudson CI
Reviewed-by: Thomas Corbat <tcorbat@hsr.ch>
Tested-by: Thomas Corbat <tcorbat@hsr.ch>

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/ast/IASTUnaryExpression.java

@@ -106,29 +106,30 @@ public interface IASTUnaryExpression extends IASTExpression {
 	@Deprecated
 	public static final int op_typeof = 14;
 	
-	/**
-	 * For GCC parsers, only. {@code op_labelReference} is used for &&label type
-	 * expressions.
-	 */
-	public static final int op_labelReference = 15;
-	
 	/**
 	 * For GCC parsers, only. {@code op_alignOf} is used for __alignOf( unaryExpression ) type
 	 * expressions.
 	 */
-	public static final int op_alignOf = 16;
+	public static final int op_alignOf = 15;
 
 	/**
 	 * For C++, only: 'sizeof... ( parameterPack )'
 	 * @since 5.2
 	 */
-	public static final int op_sizeofParameterPack = 17;
+	public static final int op_sizeofParameterPack = 16;
 
 	/**
 	 * For C++, only: noexcept ( expression )
 	 * @since 5.5
 	 */
-	public static final int op_noexcept = 18;
+	public static final int op_noexcept = 17;
+
+	/**
+	 * For GCC parsers, only. {@code op_labelReference} is used for &&label type
+	 * expressions.
+	 * @since 5.8
+	 */
+	public static final int op_labelReference = 18;
 
 	/**
 	 * {@code op_last} is made available for subclasses.

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/ast/INodeFactory.java

@@ -121,10 +121,14 @@ public interface INodeFactory {
 
 	public IGNUASTCompoundStatementExpression newGNUCompoundStatementExpression(IASTCompoundStatement compoundStatement);
 	
-	public IASTStatement newGotoStatement(IASTName name);
+	public IASTGotoStatement newGotoStatement(IASTName name);
-	
+
+	/**
+	 * Note: Adding as separate function to avoid changing API.
+	 * @since 5.8
+	 */
 	public IASTStatement newGotoStatement(IASTExpression expression);
-	
+
 	public IASTIdExpression newIdExpression(IASTName name);
 
 	public IASTIfStatement newIfStatement(IASTExpression condition, IASTStatement then, IASTStatement elseClause);

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/ast/gnu/IGNUASTGotoStatement.java

@@ -24,7 +24,7 @@ import org.eclipse.cdt.core.dom.ast.IASTStatement;
  *   goto *labelPtr;
  * </code>
  * 
- * @since 8.4
+ * @since 5.8
  * @noextend This interface is not intended to be extended by clients.
  * @noimplement This interface is not intended to be implemented by clients.
  */

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/c/CNodeFactory.java

@@ -41,6 +41,7 @@ import org.eclipse.cdt.core.dom.ast.IASTForStatement;
 import org.eclipse.cdt.core.dom.ast.IASTFunctionCallExpression;
 import org.eclipse.cdt.core.dom.ast.IASTFunctionDeclarator;
 import org.eclipse.cdt.core.dom.ast.IASTFunctionDefinition;
+import org.eclipse.cdt.core.dom.ast.IASTGotoStatement;
 import org.eclipse.cdt.core.dom.ast.IASTIdExpression;
 import org.eclipse.cdt.core.dom.ast.IASTIfStatement;
 import org.eclipse.cdt.core.dom.ast.IASTInitializer;
@@ -298,7 +299,7 @@ public class CNodeFactory extends NodeFactory implements ICNodeFactory {
 	}
 	
 	@Override
-	public IASTStatement newGotoStatement(IASTName name) {
+	public IASTGotoStatement newGotoStatement(IASTName name) {
 		return new CASTGotoStatement(name);
 	}
 	

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/c/GNUCASTGotoStatement.java

@@ -24,14 +24,14 @@ import org.eclipse.cdt.internal.core.dom.parser.ASTAttributeOwner;
  *   void *labelPtr = &&foo;
  *   goto *labelPtr; // this is the statement
  * </code>
- *  @since 8.4
+ * 
+ * @since 5.8
  */
-public class GNUCASTGotoStatement extends ASTAttributeOwner
+public class GNUCASTGotoStatement extends ASTAttributeOwner implements IGNUASTGotoStatement {
-		implements IGNUASTGotoStatement {
+	private IASTExpression fExpression;
-    private IASTExpression fExpression;
+
-    
+	public GNUCASTGotoStatement() {
-    public GNUCASTGotoStatement() {
+	}
-    }
 
 	public GNUCASTGotoStatement(IASTExpression expression) {
 		setLabelNameExpression(expression);
@@ -41,7 +41,7 @@ public class GNUCASTGotoStatement extends ASTAttributeOwner
 	public GNUCASTGotoStatement copy() {
 		return copy(CopyStyle.withoutLocations);
 	}
-	
+
 	@Override
 	public GNUCASTGotoStatement copy(CopyStyle style) {
 		GNUCASTGotoStatement copy = new GNUCASTGotoStatement();
@@ -49,24 +49,27 @@ public class GNUCASTGotoStatement extends ASTAttributeOwner
 		return copy(copy, style);
 	}
 
-    @Override
+	@Override
 	public boolean accept(ASTVisitor action) {
-        if (action.shouldVisitExpressions) {
+		if (action.shouldVisitExpressions) {
-		    switch (action.visit(this)) {
+			switch (action.visit(this)) {
-	            case ASTVisitor.PROCESS_ABORT: return false;
+			case ASTVisitor.PROCESS_ABORT:
-	            case ASTVisitor.PROCESS_SKIP: return true;
+				return false;
-	            default: break;
+			case ASTVisitor.PROCESS_SKIP:
-	        }
+				return true;
+			default:
+				break;
+			}
 		}
-      
+
 		if (fExpression != null && !fExpression.accept(action))
-			return false;        
+			return false;
 
 		if (action.shouldVisitExpressions && action.leave(this) == ASTVisitor.PROCESS_ABORT)
 			return false;
 
 		return true;
-    }
+	}
 
 	@Override
 	public IASTExpression getLabelNameExpression() {
@@ -77,13 +80,13 @@ public class GNUCASTGotoStatement extends ASTAttributeOwner
 	public void setLabelNameExpression(IASTExpression expression) {
 		assertNotFrozen();
 		this.fExpression = expression;
-		
+
 		if (expression != null) {
 			expression.setParent(this);
 			expression.setPropertyInParent(LABEL_NAME);
-		}		
+		}
 	}
-	
+
 	@Override
 	public int getRoleForName(IASTName n) {
 		return r_unclear;

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

@@ -32,6 +32,7 @@ import org.eclipse.cdt.core.dom.ast.IASTEqualsInitializer;
 import org.eclipse.cdt.core.dom.ast.IASTExpression;
 import org.eclipse.cdt.core.dom.ast.IASTExpressionStatement;
 import org.eclipse.cdt.core.dom.ast.IASTFunctionDeclarator;
+import org.eclipse.cdt.core.dom.ast.IASTGotoStatement;
 import org.eclipse.cdt.core.dom.ast.IASTIdExpression;
 import org.eclipse.cdt.core.dom.ast.IASTInitializer;
 import org.eclipse.cdt.core.dom.ast.IASTInitializerClause;
@@ -430,7 +431,7 @@ public class CPPNodeFactory extends NodeFactory implements ICPPNodeFactory {
 	}
 	
 	@Override
-	public IASTStatement newGotoStatement(IASTName name) {
+	public IASTGotoStatement newGotoStatement(IASTName name) {
 		return new CPPASTGotoStatement(name);
 	}
 

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

@@ -25,12 +25,12 @@ import org.eclipse.cdt.internal.core.dom.parser.ASTAttributeOwner;
  *   goto *labelPtr; // this is the statement
  * </code>
  * 
- * @since 8.4
+ * @since 5.8
  */
 public class GNUCPPASTGotoStatement extends ASTAttributeOwner implements IGNUASTGotoStatement {
 	private IASTExpression expression;
-	
+
-    public GNUCPPASTGotoStatement() {
+	public GNUCPPASTGotoStatement() {
 	}
 
 	public GNUCPPASTGotoStatement(IASTExpression expression) {
@@ -41,35 +41,44 @@ public class GNUCPPASTGotoStatement extends ASTAttributeOwner implements IGNUAST
 	public GNUCPPASTGotoStatement copy() {
 		return copy(CopyStyle.withoutLocations);
 	}
-	
+
 	@Override
 	public GNUCPPASTGotoStatement copy(CopyStyle style) {
-		GNUCPPASTGotoStatement copy = new GNUCPPASTGotoStatement(expression == null ? null : expression.copy(style));
+		GNUCPPASTGotoStatement copy = new GNUCPPASTGotoStatement(expression == null ? null
+				: expression.copy(style));
 		return copy(copy, style);
 	}
 
 	@Override
 	public boolean accept(ASTVisitor action) {
-        if (action.shouldVisitStatements) {
+		if (action.shouldVisitStatements) {
-		    switch (action.visit(this)) {
+			switch (action.visit(this)) {
-	            case ASTVisitor.PROCESS_ABORT : return false;
+			case ASTVisitor.PROCESS_ABORT:
-	            case ASTVisitor.PROCESS_SKIP  : return true;
+				return false;
-	            default : break;
+			case ASTVisitor.PROCESS_SKIP:
-	        }
+				return true;
+			default:
+				break;
+			}
 		}
 
-        if (!acceptByAttributeSpecifiers(action)) return false;
+		if (!acceptByAttributeSpecifiers(action))
-        if (expression != null && !expression.accept(action)) return false;
+			return false;
+		if (expression != null && !expression.accept(action))
+			return false;
 
-        if (action.shouldVisitStatements) {
+		if (action.shouldVisitStatements) {
-		    switch (action.leave(this)) {
+			switch (action.leave(this)) {
-	            case ASTVisitor.PROCESS_ABORT : return false;
+			case ASTVisitor.PROCESS_ABORT:
-	            case ASTVisitor.PROCESS_SKIP  : return true;
+				return false;
-	            default : break;
+			case ASTVisitor.PROCESS_SKIP:
-	        }
+				return true;
+			default:
+				break;
+			}
 		}
-        return true;
+		return true;
-    }
+	}
 
 	@Override
 	public IASTExpression getLabelNameExpression() {
@@ -78,15 +87,15 @@ public class GNUCPPASTGotoStatement extends ASTAttributeOwner implements IGNUAST
 
 	@Override
 	public void setLabelNameExpression(IASTExpression expression) {
-    	assertNotFrozen();
+		assertNotFrozen();
-    	this.expression = expression;
+		this.expression = expression;
-    	
+
-    	if (expression != null) {
+		if (expression != null) {
-    		expression.setParent(this);
+			expression.setParent(this);
-    		expression.setPropertyInParent(LABEL_NAME);
+			expression.setPropertyInParent(LABEL_NAME);
-    	}
+		}
 	}
-	
+
 	@Override
 	public int getRoleForName(IASTName n) {
 		return r_unclear;