diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTests.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTests.java
index ab4ab50e37b..d5c1d13ea53 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTests.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTests.java
@@ -10094,7 +10094,7 @@ public class AST2CPPTests extends AST2TestBase {
 		assertInstance(sDefinition, ICPPASTCompositeTypeSpecifier.class);
 		assertTrue(((ICPPASTCompositeTypeSpecifier)sDefinition).isFinal());
 	}
-
+	
 	// struct S {
 	//     template<typename T>
 	// 	   void foo(T t) final {
@@ -10134,6 +10134,16 @@ public class AST2CPPTests extends AST2TestBase {
 	public void testFinalParameter() throws Exception {
 		parseAndCheckBindings();
 	}
+	
+	//	struct S __final {};
+	//	struct T { void foo() __final; };
+	public void testFinalGccExtension_442457() throws Exception {
+		BindingAssertionHelper bh = getAssertionHelper();
+		ICPPClassType s = bh.assertNonProblem("S");
+		assertTrue(s.isFinal());
+		ICPPMethod foo = bh.assertNonProblem("foo");
+		assertTrue(foo.isFinal());
+	}
 
 	//	struct S1 {};
 	//	S1 s1;
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/AbstractCPPParserExtensionConfiguration.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/AbstractCPPParserExtensionConfiguration.java
index 07f3913ca02..8f7fe9ce6f8 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/AbstractCPPParserExtensionConfiguration.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/AbstractCPPParserExtensionConfiguration.java
@@ -11,8 +11,13 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.dom.parser.cpp;
 
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
 import org.eclipse.cdt.core.dom.parser.IBuiltinBindingsProvider;
 import org.eclipse.cdt.core.parser.ParserLanguage;
+import org.eclipse.cdt.core.parser.IToken.ContextSensitiveTokenType;
 import org.eclipse.cdt.internal.core.dom.parser.GCCBuiltinSymbolProvider;
 
 
@@ -161,4 +166,12 @@ public abstract class AbstractCPPParserExtensionConfiguration implements ICPPPar
 	public IBuiltinBindingsProvider getBuiltinBindingsProvider() {
 		return new GCCBuiltinSymbolProvider(ParserLanguage.CPP, supportGCCOtherBuiltinSymbols());
 	}
+	
+	/**
+	 * @since 5.9
+	 */
+	@Override
+	public Map<String, ContextSensitiveTokenType> getAdditionalContextSensitiveKeywords() {
+		return Collections.emptyMap();
+	}
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/GPPParserExtensionConfiguration.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/GPPParserExtensionConfiguration.java
index 23258d5da2b..d67fffb03b7 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/GPPParserExtensionConfiguration.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/GPPParserExtensionConfiguration.java
@@ -12,8 +12,13 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.dom.parser.cpp;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import org.eclipse.cdt.core.dom.parser.IBuiltinBindingsProvider;
+import org.eclipse.cdt.core.parser.GCCKeywords;
 import org.eclipse.cdt.core.parser.ParserLanguage;
+import org.eclipse.cdt.core.parser.IToken.ContextSensitiveTokenType;
 import org.eclipse.cdt.internal.core.dom.parser.GCCBuiltinSymbolProvider;
 
 /**
@@ -131,4 +136,12 @@ public class GPPParserExtensionConfiguration extends AbstractCPPParserExtensionC
 	public IBuiltinBindingsProvider getBuiltinBindingsProvider() {
 		return new GCCBuiltinSymbolProvider(ParserLanguage.CPP, true);
 	}
+	
+	@Override
+	public Map<String, ContextSensitiveTokenType> getAdditionalContextSensitiveKeywords() {
+		Map<String, ContextSensitiveTokenType> result = 
+				new HashMap<>(super.getAdditionalContextSensitiveKeywords());
+		result.put(GCCKeywords.__FINAL, ContextSensitiveTokenType.FINAL);
+		return result;
+	}
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/ICPPParserExtensionConfiguration.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/ICPPParserExtensionConfiguration.java
index 53779093bb4..6be67d8b69f 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/ICPPParserExtensionConfiguration.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/dom/parser/cpp/ICPPParserExtensionConfiguration.java
@@ -13,8 +13,11 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.dom.parser.cpp;
 
+import java.util.Map;
+
 import org.eclipse.cdt.core.dom.parser.IBuiltinBindingsProvider;
 import org.eclipse.cdt.core.dom.parser.IScannerExtensionConfiguration;
+import org.eclipse.cdt.core.parser.IToken.ContextSensitiveTokenType;
 
 /**
  * C++ parser extension configuration interface.
@@ -146,6 +149,12 @@ public interface ICPPParserExtensionConfiguration {
 	 */
 	public boolean supportFunctionStyleAssembler();
 
+	/**
+	 * Additional variants of context-sensitive keywords.
+	 * @since 5.9
+	 */
+	public Map<String, ContextSensitiveTokenType> getAdditionalContextSensitiveKeywords();
+	
 	/**
 	 * @deprecated use {@link #getBuiltinBindingsProvider()} instead.
 	 */
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/GCCKeywords.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/GCCKeywords.java
index e4bedec191d..9770db2f6b9 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/GCCKeywords.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/GCCKeywords.java
@@ -29,6 +29,8 @@ public class GCCKeywords {
 	public static final String __INT128 = "__int128";
 	/** @since 5.5 */
 	public static final String __FLOAT128 = "__float128";
+	/** @since 5.9 */
+	public static final String __FINAL = "__final";
 
 	public static final char[]
 		cpTYPEOF = 			TYPEOF.toCharArray(),
@@ -84,4 +86,8 @@ public class GCCKeywords {
 	public static final char[]
 		cp__is_final= 					"__is_final".toCharArray(),
 		cp__underlying_type=			"__underlying_type".toCharArray();
+	
+	/** @since 5.9 */
+	public static final char[]
+		cp__FINAL=						__FINAL.toCharArray();
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/IToken.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/IToken.java
index 4917bf17d8f..f90daa171ca 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/IToken.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/IToken.java
@@ -216,6 +216,15 @@ public interface IToken {
 
 	int FIRST_RESERVED_IExtensionToken	= 243;
 	int LAST_RESERVED_IExtensionToken	= 299;
+	
+	/**
+	 * Token types for context-sensitive tokens.
+	 * @since 5.9
+	 */
+	enum ContextSensitiveTokenType {
+		OVERRIDE,
+		FINAL
+	}
 
 
 	/**
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/Keywords.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/Keywords.java
index d2097e47c99..52284de7bd2 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/Keywords.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/Keywords.java
@@ -65,6 +65,8 @@ public class Keywords {
 	public static final String EXPORT = "export";
 	public static final String EXTERN = "extern";
 	public static final String FALSE = "false";
+	/** @since 5.9 */
+	public static final String FINAL = "final";
 	public static final String FLOAT = "float";
 	public static final String FOR = "for";
 	public static final String FRIEND = "friend";
@@ -86,6 +88,8 @@ public class Keywords {
 	public static final String OPERATOR = "operator";
 	public static final String OR = "or";
 	public static final String OR_EQ = "or_eq";
+	/** @since 5.9 */
+	public static final String OVERRIDE = "override";
 	public static final String PRIVATE = "private";
 	public static final String PROTECTED = "protected";
 	public static final String PUBLIC = "public";
@@ -169,7 +173,7 @@ public class Keywords {
 	public static final char[] cFLOAT = "float".toCharArray();
 	public static final char[] cFOR = "for".toCharArray();
 	/** @since 5.5 */
-	public static final char[] cFINAL = "final".toCharArray();
+	public static final char[] cFINAL = FINAL.toCharArray();
 	public static final char[] cFRIEND = "friend".toCharArray();
 	public static final char[] cGOTO = "goto".toCharArray();
 	public static final char[] cIF = "if".toCharArray();
@@ -189,7 +193,7 @@ public class Keywords {
 	public static final char[] cOR = "or".toCharArray();
 	public static final char[] cOR_EQ = "or_eq".toCharArray();
 	/** @since 5.5 */
-	public static final char[] cOVERRIDE = "override".toCharArray();
+	public static final char[] cOVERRIDE = OVERRIDE.toCharArray();
 	public static final char[] cPRIVATE = "private".toCharArray();
 	public static final char[] cPROTECTED = "protected".toCharArray();
 	public static final char[] cPUBLIC = "public".toCharArray();
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/GNUCPPSourceParser.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/GNUCPPSourceParser.java
index 6377117b0e7..1edb957f6cc 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/GNUCPPSourceParser.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/GNUCPPSourceParser.java
@@ -19,9 +19,10 @@
 package org.eclipse.cdt.internal.core.dom.parser.cpp;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 import org.eclipse.cdt.core.dom.ast.ASTVisitor;
 import org.eclipse.cdt.core.dom.ast.DOMException;
@@ -145,6 +146,7 @@ import org.eclipse.cdt.core.parser.IParserLogService;
 import org.eclipse.cdt.core.parser.IProblem;
 import org.eclipse.cdt.core.parser.IScanner;
 import org.eclipse.cdt.core.parser.IToken;
+import org.eclipse.cdt.core.parser.IToken.ContextSensitiveTokenType;
 import org.eclipse.cdt.core.parser.Keywords;
 import org.eclipse.cdt.core.parser.ParserMode;
 import org.eclipse.cdt.core.parser.util.ArrayUtil;
@@ -189,6 +191,8 @@ public class GNUCPPSourceParser extends AbstractGNUSourceCodeParser {
 
 	private final ICPPNodeFactory nodeFactory;
 	private TemplateIdStrategy fTemplateParameterListStrategy;
+	
+	private Map<String, ContextSensitiveTokenType> fContextSensitiveTokens;
 
     public GNUCPPSourceParser(IScanner scanner, ParserMode mode,
             IParserLogService log, ICPPParserExtensionConfiguration config) {
@@ -215,8 +219,25 @@ public class GNUCPPSourceParser extends AbstractGNUSourceCodeParser {
         this.index= index;
         this.nodeFactory = CPPNodeFactory.getDefault();
         scanner.setSplitShiftROperator(true);
+        fContextSensitiveTokens = createContextSensitiveTokenMap(config);
     }
-
+    
+    private Map<String, ContextSensitiveTokenType> createContextSensitiveTokenMap(
+    		ICPPParserExtensionConfiguration config) {
+    	Map<String, ContextSensitiveTokenType> result = new HashMap<String, ContextSensitiveTokenType>();
+    	result.put(Keywords.OVERRIDE, ContextSensitiveTokenType.OVERRIDE);
+    	result.put(Keywords.FINAL, ContextSensitiveTokenType.FINAL);
+    	result.putAll(config.getAdditionalContextSensitiveKeywords());
+    	return result;
+    }
+    
+    private ContextSensitiveTokenType getContextSensitiveType(IToken token) {
+    	if (!(token.getType() == IToken.tIDENTIFIER)) {
+    		return null;
+    	}
+		return fContextSensitiveTokens.get(new String(token.getCharImage()));
+    }
+    
     @Override
 	protected IASTName identifier() throws EndOfFileException, BacktrackException {
     	switch (LT(1)) {
@@ -3640,16 +3661,14 @@ public class GNUCPPSourceParser extends AbstractGNUSourceCodeParser {
     		throws EndOfFileException, BacktrackException {
     	while (true) {
     		IToken token = LAcatchEOF(1);
-    		if (token.getType() != IToken.tIDENTIFIER)
-    			break;
-    		char[] tokenImage = token.getCharImage();
-    		if (Arrays.equals(Keywords.cOVERRIDE, tokenImage)) {
+    		ContextSensitiveTokenType contextSensitiveType = getContextSensitiveType(token);
+    		if (contextSensitiveType == ContextSensitiveTokenType.OVERRIDE) {
     			consume();
     			ICPPASTVirtSpecifier spec = nodeFactory.newVirtSpecifier(
     					ICPPASTVirtSpecifier.SpecifierKind.Override);
     			setRange(spec, token.getOffset(), token.getOffset() + token.getLength());
     			typeRelevantDtor.addVirtSpecifier(spec);
-    		} else if (Arrays.equals(Keywords.cFINAL, tokenImage)) {
+    		} else if (contextSensitiveType == ContextSensitiveTokenType.FINAL) {
     			consume();
     			ICPPASTVirtSpecifier spec = nodeFactory.newVirtSpecifier(
     					ICPPASTVirtSpecifier.SpecifierKind.Final);
@@ -4489,8 +4508,8 @@ public class GNUCPPSourceParser extends AbstractGNUSourceCodeParser {
      */
 	private void classVirtSpecifier(ICPPASTCompositeTypeSpecifier astClassSpecifier) throws EndOfFileException, BacktrackException {
 		IToken token = LA();
-		char[] tokenImage = token.getCharImage();
-		if (token.getType() == IToken.tIDENTIFIER && Arrays.equals(Keywords.cFINAL, tokenImage)){
+		ContextSensitiveTokenType contextSensitiveType = getContextSensitiveType(token);
+		if (contextSensitiveType == ContextSensitiveTokenType.FINAL) {
 			consume();
 			ICPPASTClassVirtSpecifier spec = nodeFactory.newClassVirtSpecifier(
 					ICPPASTClassVirtSpecifier.SpecifierKind.Final);