Partial fix for https://bugs.eclipse.org/bugs/show_bug.cgi?id=65610

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/QuickParseASTTests.java

@@ -2244,4 +2244,10 @@ public class QuickParseASTTests extends BaseASTTest
 			assertFalse( iter.hasNext() );
     	}
 	}
+    
+    public void testBadIdentifier() throws Exception
+	{
+    	parse( "class 0302 { private: int stinks; };", true, false ); //$NON-NLS-1$
+    	
+	}
 }

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/core/parser/BacktrackException.java

@@ -16,4 +16,53 @@ package org.eclipse.cdt.core.parser;
  */
 public class BacktrackException extends Exception
 {
+
+	private IProblem problem;
+	private int startOffset;
+	private int endOffset;
+
+	/**
+	 * @param p
+	 */
+	public void initialize(IProblem p) {
+		reset();
+		problem = p;
+	}
+
+	/**
+	 * 
+	 */
+	private void reset() {
+		problem = null;
+		startOffset = 0;
+		endOffset = 0;
+	}
+	/**
+	 * @return Returns the problem.
+	 */
+	public final IProblem getProblem() {
+		return problem;
+	}
+
+	/**
+	 * @param startingOffset
+	 * @param endingOffset
+	 */
+	public void initialize(int startingOffset, int endingOffset) {
+		reset();
+		startOffset = startingOffset;
+		endOffset = endingOffset;
+	}
+	/**
+	 * @return Returns the offset.
+	 */
+	public final int getStartingOffset() {
+		return startOffset;
+	}
+	/**
+	 * @return Returns the endOffset.
+	 */
+	public final int getEndOffset() {
+		return endOffset;
+	}
 }

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/parser/CompletionParser.java

@@ -131,7 +131,9 @@ public class CompletionParser extends ContextualParser implements IParser {
 	protected void catchHandlerSequence(IASTScope scope)
 	throws EndOfFileException, BacktrackException {
 		if( LT(1) != IToken.t_catch )
-			throw backtrack; // error, need at least one of these
+		{
+			throwBacktrack(LA(1).getOffset()); // error, need at least one of these
+		}
 		while (LT(1) == IToken.t_catch)
 		{
 			consume(IToken.t_catch);