diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/BaseScannerTest.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/BaseScannerTest.java
index 1340a22010f..1dbded359f5 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/BaseScannerTest.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/BaseScannerTest.java
@@ -47,7 +47,7 @@ public class BaseScannerTest extends TestCase {
 
 	protected void initializeScanner( String input, ParserMode mode, ISourceElementRequestor requestor ) throws ParserFactoryError
 	{
-		scanner= ParserFactory.createScanner( new StringReader(input),"TEXT", new ScannerInfo(), mode, ParserLanguage.CPP, requestor, null, null );
+		scanner= ParserFactory.createScanner( new StringReader(input),"TEXT", new ScannerInfo(), mode, ParserLanguage.CPP, requestor, null, null ); //$NON-NLS-1$
 	}
 
 	protected void initializeScanner(String input) throws ParserFactoryError
@@ -65,10 +65,10 @@ public class BaseScannerTest extends TestCase {
 			while (t != null)
 			{
 				if (verbose)
-					System.out.println("Token t = " + t);
+					System.out.println("Token t = " + t); //$NON-NLS-1$
 
 				if ((t.getType()> IToken.tLAST))
-					System.out.println("Unknown type for token " + t);
+					System.out.println("Unknown type for token " + t); //$NON-NLS-1$
 				t= scanner.nextToken();
 			}
 		}
@@ -208,10 +208,10 @@ public class BaseScannerTest extends TestCase {
 		assertNull(scanner.getDefinition(name));
 	}
 
-	public static final String EXCEPTION_THROWN = "Exception thrown ";
+	public static final String EXCEPTION_THROWN = "Exception thrown "; //$NON-NLS-1$
 
-	public static final String EXPECTED_FAILURE = "This statement should not be reached "
-				+ "as we sent in bad preprocessor input to the scanner";
+	public static final String EXPECTED_FAILURE = "This statement should not be reached " //$NON-NLS-1$
+				+ "as we sent in bad preprocessor input to the scanner"; //$NON-NLS-1$
 
 	public static final boolean verbose = false;
 
diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ScannerTestCase.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ScannerTestCase.java
index 3779aaf9e3b..956872351f8 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ScannerTestCase.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ScannerTestCase.java
@@ -1572,4 +1572,10 @@ public class ScannerTestCase extends BaseScannerTest
     	fullyTokenize();
     	assertTrue( callback.problems.isEmpty() );
 	}
+    
+    public void testBug62378() throws Exception
+	{
+    	initializeScanner( "\"\\?\\?<\""); //$NON-NLS-1$
+    	validateString("\\?\\?<" ); //$NON-NLS-1$
+	}
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/Scanner.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/Scanner.java
index cd5a7994dc0..1025946c75b 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/Scanner.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/Scanner.java
@@ -958,7 +958,6 @@ public class Scanner implements IScanner {
 			{
 				// TODO : we could probably return the partial string -- it might cause 
 				// the parse to get by...
-				
 				handleProblem( IProblem.SCANNER_UNBOUNDED_STRING, null, beginOffset, false, true );
 				return null;
 			}
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/ScannerContextInclusion.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/ScannerContextInclusion.java
index 02949dc881c..b9a9ab3533d 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/ScannerContextInclusion.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/scanner/ScannerContextInclusion.java
@@ -18,6 +18,7 @@ import org.eclipse.cdt.core.parser.ast.IASTInclusion;
 
 public class ScannerContextInclusion implements IScannerContext
 {
+	public static final int UNDO_BUFFER_SIZE = 4;
 	protected Reader reader;
 	private String filename;
 	private IASTInclusion inc;
@@ -52,7 +53,7 @@ public class ScannerContextInclusion implements IScannerContext
 		}
 	}
 	protected int pos = 0;
-	protected int undo[] = new int[2];  
+	protected int undo[] = new int[UNDO_BUFFER_SIZE];  
 	public final void ungetChar(int c) {
 		undo[pos++] = c; 
 	}