Index: lucene/core/src/test/org/apache/lucene/index/TestCheckIndex.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/index/TestCheckIndex.java	(revision 1361692)
+++ lucene/core/src/test/org/apache/lucene/index/TestCheckIndex.java	(working copy)
@@ -25,8 +25,11 @@
 
 import org.apache.lucene.util.LuceneTestCase;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.analysis.CannedTokenStream;
 import org.apache.lucene.analysis.MockAnalyzer;
+import org.apache.lucene.analysis.Token;
 import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
 import org.apache.lucene.document.FieldType;
 import org.apache.lucene.document.TextField;
 import org.apache.lucene.util.Constants;
@@ -93,6 +96,24 @@
     assertTrue(checker.checkIndex(onlySegments).clean == true);
     dir.close();
   }
+  
+  // LUCENE-4221: we have to let these thru, for now
+  public void testBogusTermVectors() throws IOException {
+    Directory dir = newDirectory();
+    IndexWriter iw = new IndexWriter(dir, newIndexWriterConfig(TEST_VERSION_CURRENT, null));
+    Document doc = new Document();
+    FieldType ft = new FieldType(TextField.TYPE_NOT_STORED);
+    ft.setStoreTermVectors(true);
+    ft.setStoreTermVectorOffsets(true);
+    Field field = new Field("foo", "", ft);
+    field.setTokenStream(new CannedTokenStream(
+        new Token("bar", 5, 10), new Token("bar", 1, 4)
+    ));
+    doc.add(field);
+    iw.addDocument(doc);
+    iw.close();
+    dir.close(); // checkindex
+  }
 
   public void testLuceneConstantVersion() throws IOException {
     // common-build.xml sets lucene.version
Index: lucene/core/src/java/org/apache/lucene/index/CheckIndex.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/CheckIndex.java	(revision 1361692)
+++ lucene/core/src/java/org/apache/lucene/index/CheckIndex.java	(working copy)
@@ -668,7 +668,7 @@
    * checks Fields api is consistent with itself.
    * searcher is optional, to verify with queries. Can be null.
    */
-  private Status.TermIndexStatus checkFields(Fields fields, Bits liveDocs, int maxDoc, FieldInfos fieldInfos, boolean doPrint) throws IOException {
+  private Status.TermIndexStatus checkFields(Fields fields, Bits liveDocs, int maxDoc, FieldInfos fieldInfos, boolean doPrint, boolean isVectors) throws IOException {
     // TODO: we should probably return our own stats thing...?!
     
     final Status.TermIndexStatus status = new Status.TermIndexStatus();
@@ -863,18 +863,22 @@
               if (hasOffsets) {
                 int startOffset = postings.startOffset();
                 int endOffset = postings.endOffset();
-                if (startOffset < 0) {
-                  throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": startOffset " + startOffset + " is out of bounds");
+                // NOTE: we cannot enforce any bounds whatsoever on vectors... they were a free-for-all before?
+                // but for offsets in the postings lists these checks are fine: they were always enforced by IndexWriter
+                if (!isVectors) {
+                  if (startOffset < 0) {
+                    throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": startOffset " + startOffset + " is out of bounds");
+                  }
+                  if (startOffset < lastOffset) {
+                    throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": startOffset " + startOffset + " < lastStartOffset " + lastOffset);
+                  }
+                  if (endOffset < 0) {
+                    throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": endOffset " + endOffset + " is out of bounds");
+                  }
+                  if (endOffset < startOffset) {
+                    throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": endOffset " + endOffset + " < startOffset " + startOffset);
+                  }
                 }
-                if (startOffset < lastOffset) {
-                  throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": startOffset " + startOffset + " < lastStartOffset " + lastOffset);
-                }
-                if (endOffset < 0) {
-                  throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": endOffset " + endOffset + " is out of bounds");
-                }
-                if (endOffset < startOffset) {
-                  throw new RuntimeException("term " + term + ": doc " + doc + ": pos " + pos + ": endOffset " + endOffset + " < startOffset " + startOffset);
-                }
                 lastOffset = startOffset;
               }
             }
@@ -956,18 +960,22 @@
                 if (hasOffsets) {
                   int startOffset = postings.startOffset();
                   int endOffset = postings.endOffset();
-                  if (startOffset < 0) {
-                    throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": startOffset " + startOffset + " is out of bounds");
+                  // NOTE: we cannot enforce any bounds whatsoever on vectors... they were a free-for-all before?
+                  // but for offsets in the postings lists these checks are fine: they were always enforced by IndexWriter
+                  if (!isVectors) {
+                    if (startOffset < 0) {
+                      throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": startOffset " + startOffset + " is out of bounds");
+                    }
+                    if (startOffset < lastOffset) {
+                      throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": startOffset " + startOffset + " < lastStartOffset " + lastOffset);
+                    }
+                    if (endOffset < 0) {
+                      throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": endOffset " + endOffset + " is out of bounds");
+                    }
+                    if (endOffset < startOffset) {
+                      throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": endOffset " + endOffset + " < startOffset " + startOffset);
+                    }
                   }
-                  if (startOffset < lastOffset) {
-                    throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": startOffset " + startOffset + " < lastStartOffset " + lastOffset);
-                  }
-                  if (endOffset < 0) {
-                    throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": endOffset " + endOffset + " is out of bounds");
-                  }
-                  if (endOffset < startOffset) {
-                    throw new RuntimeException("term " + term + ": doc " + docID + ": pos " + pos + ": endOffset " + endOffset + " < startOffset " + startOffset);
-                  }
                   lastOffset = startOffset;
                 }
               } 
@@ -1193,12 +1201,12 @@
       }
 
       final Fields fields = reader.fields();
-      status = checkFields(fields, liveDocs, maxDoc, fieldInfos, true);
+      status = checkFields(fields, liveDocs, maxDoc, fieldInfos, true, false);
       if (liveDocs != null) {
         if (infoStream != null) {
           infoStream.print("    test (ignoring deletes): terms, freq, prox...");
         }
-        checkFields(fields, null, maxDoc, fieldInfos, true);
+        checkFields(fields, null, maxDoc, fieldInfos, true, false);
       }
     } catch (Throwable e) {
       msg("ERROR: " + e);
@@ -1415,10 +1423,10 @@
 
         if (tfv != null) {
           // First run with no deletions:
-          checkFields(tfv, null, 1, fieldInfos, false);
+          checkFields(tfv, null, 1, fieldInfos, false, true);
 
           // Again, with the one doc deleted:
-          checkFields(tfv, onlyDocIsDeleted, 1, fieldInfos, false);
+          checkFields(tfv, onlyDocIsDeleted, 1, fieldInfos, false, true);
 
           // Only agg stats if the doc is live:
           final boolean doStats = liveDocs == null || liveDocs.get(j);