GCC allows forward declarations of enums in C

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2Tests.java

@@ -55,6 +55,7 @@ import org.eclipse.cdt.core.dom.ast.IFunctionType;
 import org.eclipse.cdt.core.dom.ast.ILabel;
 import org.eclipse.cdt.core.dom.ast.IParameter;
 import org.eclipse.cdt.core.dom.ast.IPointerType;
+import org.eclipse.cdt.core.dom.ast.IProblemBinding;
 import org.eclipse.cdt.core.dom.ast.IQualifierType;
 import org.eclipse.cdt.core.dom.ast.IScope;
 import org.eclipse.cdt.core.dom.ast.IType;
@@ -2600,4 +2601,22 @@ public class AST2Tests extends AST2BaseTest {
        assertEquals( ps.length, 1 );
        ps[0].getMessage();
    }
+
+   public void testEnumerationForwards() throws Exception{
+       StringBuffer buffer = new StringBuffer();
+       buffer.append( "enum e;          \n;" ); //$NON-NLS-1$
+       buffer.append( "enum e{ one };   \n;" ); //$NON-NLS-1$
+
+       IASTTranslationUnit tu = parse(buffer.toString(), ParserLanguage.C);
+       CNameCollector col = new CNameCollector();
+       CVisitor.visitTranslationUnit(tu, col);
+
+       assertEquals(col.size(), 3);
+       IEnumeration e = (IEnumeration) col.getName(0).resolveBinding();
+       IEnumerator[] etors = e.getEnumerators();
+       assertTrue( etors.length == 1 );
+       assertFalse( etors[0] instanceof IProblemBinding );
+       
+       assertInstances( col, e, 2 );
+   }
 }

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

@@ -14,12 +14,18 @@
  */
 package org.eclipse.cdt.internal.core.dom.parser.c;
 
+import org.eclipse.cdt.core.dom.ast.ASTNodeProperty;
+import org.eclipse.cdt.core.dom.ast.IASTDeclSpecifier;
+import org.eclipse.cdt.core.dom.ast.IASTElaboratedTypeSpecifier;
 import org.eclipse.cdt.core.dom.ast.IASTEnumerationSpecifier;
+import org.eclipse.cdt.core.dom.ast.IASTName;
 import org.eclipse.cdt.core.dom.ast.IASTNode;
 import org.eclipse.cdt.core.dom.ast.IEnumeration;
 import org.eclipse.cdt.core.dom.ast.IEnumerator;
+import org.eclipse.cdt.core.dom.ast.IProblemBinding;
 import org.eclipse.cdt.core.dom.ast.IScope;
 import org.eclipse.cdt.core.dom.ast.IType;
+import org.eclipse.cdt.core.dom.ast.c.ICASTElaboratedTypeSpecifier;
 import org.eclipse.cdt.core.dom.ast.c.ICASTEnumerationSpecifier;
 
 /**
@@ -27,34 +33,75 @@ import org.eclipse.cdt.core.dom.ast.c.ICASTEnumerationSpecifier;
  */
 public class CEnumeration implements IEnumeration {
 
-    private final ICASTEnumerationSpecifier enumSpec;
+    private IASTName [] declarations = null;
-    public CEnumeration( ICASTEnumerationSpecifier spec ){
+    private IASTName definition = null;
-		spec = checkForDefinition( spec );
+    public CEnumeration( IASTName enum ){
-		this.enumSpec = spec;
+        ASTNodeProperty prop = enum.getPropertyInParent();
+        if( prop == IASTElaboratedTypeSpecifier.TYPE_NAME )
+        	declarations = new IASTName[] { enum };
+        else
+            definition = enum;
 	}
 	
-    public IASTNode getPhysicalNode(){
+    public void addDeclaration( IASTName decl ){
-        return enumSpec;
+        if( decl.getPropertyInParent() != IASTElaboratedTypeSpecifier.TYPE_NAME )
+            return;
+            
+        if( declarations == null ){
+            declarations = new IASTName[] { decl };
+        	return;
+        }
+        for( int i = 0; i < declarations.length; i++ ){
+            if( declarations[i] == null ){
+                declarations[i] = decl;
+                return;
+            }
+        }
+        IASTName tmp [] = new IASTName [ declarations.length * 2 ];
+        System.arraycopy( declarations, 0, tmp, 0, declarations.length );
+        tmp[ declarations.length ] = decl;
+        declarations = tmp;
     }
-	private ICASTEnumerationSpecifier checkForDefinition( ICASTEnumerationSpecifier spec ){
+    
-	    return spec;
+    public IASTNode getPhysicalNode(){
+        if( definition != null )
+            return definition;
+        
+        return declarations[0];
+    }
+    
+	private void checkForDefinition(){
+		IASTDeclSpecifier spec = CVisitor.findDefinition( (ICASTElaboratedTypeSpecifier) declarations[0].getParent() );
+		if( spec != null && spec instanceof ICASTEnumerationSpecifier ){
+		    ICASTEnumerationSpecifier enumSpec = (ICASTEnumerationSpecifier) spec;
+		    
+			((CASTName)enumSpec.getName()).setBinding( this );
+			definition = enumSpec.getName();
+		}
+		return;
 	}
 	
     /* (non-Javadoc)
      * @see org.eclipse.cdt.core.dom.ast.IBinding#getName()
      */
     public String getName() {
-        return enumSpec.getName().toString();
+        if( definition != null )
+            return definition.toString();
+        
+        return declarations[0].toString();
     }
     public char[] getNameCharArray(){
-        return ((CASTName) enumSpec.getName()).toCharArray();
+        if( definition != null )
+            return definition.toCharArray();
+        
+        return declarations[0].toCharArray();
     }
 
     /* (non-Javadoc)
      * @see org.eclipse.cdt.core.dom.ast.IBinding#getScope()
      */
     public IScope getScope() {
-        return CVisitor.getContainingScope( enumSpec );
+        return CVisitor.getContainingScope( definition != null ? definition : declarations[0].getParent() );
     }
 
     public Object clone(){
@@ -71,6 +118,13 @@ public class CEnumeration implements IEnumeration {
      * @see org.eclipse.cdt.core.dom.ast.IEnumeration#getEnumerators()
      */
     public IEnumerator[] getEnumerators() {
+        if( definition == null ){
+            checkForDefinition();
+            if( definition == null )
+                return new IEnumerator[] { new CEnumerator.CEnumeratorProblem( IProblemBinding.SEMANTIC_DEFINITION_NOT_FOUND, declarations[0].toCharArray() ) };
+        }
+        
+        IASTEnumerationSpecifier enumSpec = (IASTEnumerationSpecifier) definition.getParent();
         IASTEnumerationSpecifier.IASTEnumerator[] enums = enumSpec.getEnumerators();
         IEnumerator [] bindings = new IEnumerator [ enums.length ];
         
@@ -79,4 +133,11 @@ public class CEnumeration implements IEnumeration {
         }
         return bindings;
     }
+
+    /**
+     * @param name
+     */
+    public void addDefinition( IASTName name ) {
+        definition = name;
+    }
 }

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

@@ -14,6 +14,7 @@
  */
 package org.eclipse.cdt.internal.core.dom.parser.c;
 
+import org.eclipse.cdt.core.dom.ast.DOMException;
 import org.eclipse.cdt.core.dom.ast.IASTEnumerationSpecifier;
 import org.eclipse.cdt.core.dom.ast.IASTNode;
 import org.eclipse.cdt.core.dom.ast.IEnumeration;
@@ -21,11 +22,21 @@ import org.eclipse.cdt.core.dom.ast.IEnumerator;
 import org.eclipse.cdt.core.dom.ast.IScope;
 import org.eclipse.cdt.core.dom.ast.IType;
 import org.eclipse.cdt.core.dom.ast.IASTEnumerationSpecifier.IASTEnumerator;
+import org.eclipse.cdt.internal.core.dom.parser.ProblemBinding;
 
 /**
  * @author aniefer
  */
 public class CEnumerator implements IEnumerator {
+    public static class CEnumeratorProblem extends ProblemBinding implements IEnumerator {
+        public CEnumeratorProblem( int id, char[] arg ) {
+            super( id, arg );
+        }
+
+        public IType getType() throws DOMException {
+            throw new DOMException( this );
+        }
+    }
 
     private final IASTEnumerator enumerator;
     public CEnumerator( IASTEnumerator enumtor ){

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

@@ -98,6 +98,7 @@ import org.eclipse.cdt.core.dom.ast.gnu.c.ICASTKnRFunctionDeclarator;
 import org.eclipse.cdt.core.dom.ast.gnu.c.IGCCASTArrayRangeDesignator;
 import org.eclipse.cdt.core.parser.util.CharArrayUtils;
 import org.eclipse.cdt.internal.core.dom.parser.ITypeContainer;
+import org.eclipse.cdt.internal.core.dom.parser.ProblemBinding;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPVisitor.CPPBaseVisitorAction;
 
 /**
@@ -502,11 +503,26 @@ public class CVisitor {
 	}
 
 	private static IBinding createBinding( ICASTEnumerationSpecifier enumeration ){
-	    IEnumeration binding = new CEnumeration( enumeration );
+	    IASTName name = enumeration.getName();
-	    try {
+	    ICScope scope = (ICScope) getContainingScope( enumeration );
-            ((ICScope)binding.getScope()).addBinding( binding );
+	    IBinding binding;
+        try {
+            binding = scope.getBinding( ICScope.NAMESPACE_TYPE_TAG, name.toCharArray() );
         } catch ( DOMException e ) {
+            binding = null;
         }
+        if( binding != null ){
+	        if( binding instanceof CEnumeration )
+	            ((CEnumeration)binding).addDefinition( name );
+	        else
+	            return new ProblemBinding(IProblemBinding.SEMANTIC_INVALID_OVERLOAD, name.toCharArray() );
+	    } else {
+	        binding = new CEnumeration( name );
+	        try {
+                scope.addBinding( binding );
+            } catch ( DOMException e1 ) {
+            }
+	    } 
         return binding; 
 	}
 	private static IBinding createBinding( IASTEnumerator enumerator ){
@@ -551,11 +567,20 @@ public class CVisitor {
 				//forward declaration
 				IBinding binding = resolveBinding( elabTypeSpec, CURRENT_SCOPE | TAGS );
 				if( binding == null ){
-					binding = new CStructure( elabTypeSpec );
+				    if( elabTypeSpec.getKind() == IASTElaboratedTypeSpecifier.k_enum ){
+				        binding = new CEnumeration( elabTypeSpec.getName() );
+				    } else {
+				        binding = new CStructure( elabTypeSpec );    
+				    }
+					
 					try {
                         ((ICScope) binding.getScope()).addBinding( binding );
                     } catch ( DOMException e ) {
                     }
+				} else {
+				    if( binding instanceof CEnumeration ){
+				        ((CEnumeration)binding).addDeclaration( elabTypeSpec.getName() );
+				    }
 				}
 				return binding;
 			} 
@@ -1242,10 +1267,17 @@ public class CVisitor {
 						}
 					} else if( node instanceof IASTSimpleDeclaration && decl instanceof ICASTElaboratedTypeSpecifier){
 						IASTSimpleDeclaration simpleDecl = (IASTSimpleDeclaration) node;
-						if( simpleDecl.getDeclSpecifier() instanceof ICASTCompositeTypeSpecifier ){
+						IASTDeclSpecifier declSpec = simpleDecl.getDeclSpecifier();
-							ICASTCompositeTypeSpecifier compTypeSpec = (ICASTCompositeTypeSpecifier) simpleDecl.getDeclSpecifier();
+						IASTName name = null;
-							if( CharArrayUtils.equals( compTypeSpec.getName().toCharArray(), declName ) ){
+						
-								return compTypeSpec;
+						if( declSpec instanceof ICASTCompositeTypeSpecifier ){
+						    name = ((ICASTCompositeTypeSpecifier)declSpec).getName();
+						} else if( declSpec instanceof ICASTEnumerationSpecifier ){
+						    name = ((ICASTEnumerationSpecifier)declSpec).getName();
+						}
+						if( name !=  null ){
+						    if( CharArrayUtils.equals( name.toCharArray(), declName ) ){
+								return declSpec;
 							}
 						}
 					} else if( node instanceof IASTSimpleDeclaration && decl instanceof IASTDeclarator ){