diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTestBase.java
index f8c07d3b8b0..0478f7bc461 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2CPPTestBase.java
@@ -17,7 +17,7 @@
 import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
 import org.eclipse.cdt.internal.core.parser.ParserException;
 
-public class AST2CPPTestBase extends AST2TestBase {
+public abstract class AST2CPPTestBase extends AST2TestBase {
 	public AST2CPPTestBase() {
 	}
 
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SelectionParseTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SelectionParseTestBase.java
index 1b3c460d146..26dcc792d36 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SelectionParseTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SelectionParseTestBase.java
@@ -43,7 +43,7 @@
 /**
  * @author dsteffle
  */
-public class AST2SelectionParseTestBase extends FileBasePluginTestCase {
+public abstract class AST2SelectionParseTestBase extends FileBasePluginTestCase {
 
 	public AST2SelectionParseTestBase() {
 	}
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SpecTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SpecTestBase.java
index bf22f18a414..2115fe0e6cd 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SpecTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2SpecTestBase.java
@@ -44,7 +44,7 @@
 /**
  * @author dsteffle
  */
-public class AST2SpecTestBase extends AST2TestBase {
+public abstract class AST2SpecTestBase extends AST2TestBase {
 	public AST2SpecTestBase() {
 		super();
 	}
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TestBase.java
index 755bf7bafea..5453037a149 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TestBase.java
@@ -98,7 +98,7 @@
 /**
  * @author aniefer
  */
-public class AST2TestBase extends SemanticTestBase {
+public abstract class AST2TestBase extends SemanticTestBase {
 	public final static String TEST_CODE = "<testcode>";
 	protected static final IParserLogService NULL_LOG = new NullLogService();
 	protected static boolean sValidateCopy;
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/DOMSelectionParseTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/DOMSelectionParseTestBase.java
index f4706f4842e..a166ff90014 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/DOMSelectionParseTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/DOMSelectionParseTestBase.java
@@ -26,7 +26,7 @@
  * @author johnc
  *
  */
-public class DOMSelectionParseTestBase extends DOMFileBasePluginTest {
+public abstract class DOMSelectionParseTestBase extends DOMFileBasePluginTest {
 
 	public DOMSelectionParseTestBase() {
 	}
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/SemanticTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/SemanticTestBase.java
index 2c0eb1f6876..5bfde5b13d1 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/SemanticTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/SemanticTestBase.java
@@ -35,7 +35,7 @@
 /**
  * Common base class for AST2 and index tests.
  */
-public class SemanticTestBase extends BaseTestCase {
+public abstract class SemanticTestBase extends BaseTestCase {
 	public SemanticTestBase() {
 		super();
 	}
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/prefix/CompletionTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/prefix/CompletionTestBase.java
index 9bd10dbe9d2..09d06881cbf 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/prefix/CompletionTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/prefix/CompletionTestBase.java
@@ -49,7 +49,7 @@
 
 import junit.framework.AssertionFailedError;
 
-public class CompletionTestBase extends BaseTestCase {
+public abstract class CompletionTestBase extends BaseTestCase {
 
 	private static final IParserLogService NULL_LOG = new NullLogService();
 
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexTestBase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexTestBase.java
index 2e91daf522a..84c535968d4 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexTestBase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexTestBase.java
@@ -28,7 +28,7 @@
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 
-public class IndexTestBase extends BaseTestCase {
+public abstract class IndexTestBase extends BaseTestCase {
 	public IndexTestBase(String name) {
 		super(name);
 	}