diff --git a/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java b/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
index 7abf681fe88..4517294f4c3 100644
--- a/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
+++ b/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
@@ -1898,7 +1898,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
             final int size = mergeExceptions.size();
             for(int i=0;i<size;i++) {
               final MergePolicy.OneMerge merge = mergeExceptions.get(i);
-              if (merge.maxNumSegments != -1) {
+              if (merge.maxNumSegments != UNBOUNDED_MAX_MERGE_SEGMENTS) {
                 throw new IOException("background merge hit exception: " + merge.segString(), merge.getException());
               }
             }
@@ -1926,12 +1926,12 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
    *  runningMerges are maxNumSegments merges. */
   private synchronized boolean maxNumSegmentsMergesPending() {
     for (final MergePolicy.OneMerge merge : pendingMerges) {
-      if (merge.maxNumSegments != -1)
+      if (merge.maxNumSegments != UNBOUNDED_MAX_MERGE_SEGMENTS)
         return true;
     }
 
     for (final MergePolicy.OneMerge merge : runningMerges) {
-      if (merge.maxNumSegments != -1)
+      if (merge.maxNumSegments != UNBOUNDED_MAX_MERGE_SEGMENTS)
         return true;
     }
 
@@ -2059,7 +2059,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
     // point, try again to log the config here:
     messageState();
 
-    assert maxNumSegments == -1 || maxNumSegments > 0;
+    assert maxNumSegments == UNBOUNDED_MAX_MERGE_SEGMENTS || maxNumSegments > 0;
     assert trigger != null;
     if (stopMerges) {
       return false;
@@ -2771,7 +2771,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
       // Best-effort up front check:
       testReserveDocs(numDocs);
 
-      final IOContext context = new IOContext(new MergeInfo(Math.toIntExact(numDocs), -1, false, -1));
+      final IOContext context = new IOContext(new MergeInfo(Math.toIntExact(numDocs), -1, false, UNBOUNDED_MAX_MERGE_SEGMENTS));
 
       // TODO: somehow we should fix this merge so it's
       // abortable so that IW.close(false) is able to stop it
@@ -3797,7 +3797,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
       infoStream.message("IW", "after commitMerge: " + segString());
     }
 
-    if (merge.maxNumSegments != -1 && !dropSegment) {
+    if (merge.maxNumSegments != UNBOUNDED_MAX_MERGE_SEGMENTS && !dropSegment) {
       // cascade the forceMerge:
       if (!segmentsToMerge.containsKey(merge.info)) {
         segmentsToMerge.put(merge.info, Boolean.FALSE);
@@ -3876,7 +3876,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
             if (infoStream.isEnabled("IW")) {
               infoStream.message("IW", "hit exception during merge");
             }
-          } else if (merge.rateLimiter.getAbort() == false && (merge.maxNumSegments != -1 || (!closed && !closing))) {
+          } else if (merge.rateLimiter.getAbort() == false && (merge.maxNumSegments != UNBOUNDED_MAX_MERGE_SEGMENTS || (!closed && !closing))) {
             // This merge (and, generally, any change to the
             // segments) may now enable new merges, so we call
             // merge policy & update pending merges.
@@ -4015,7 +4015,7 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable {
     testPoint("startMergeInit");
 
     assert merge.registerDone;
-    assert merge.maxNumSegments == -1 || merge.maxNumSegments > 0;
+    assert merge.maxNumSegments == UNBOUNDED_MAX_MERGE_SEGMENTS || merge.maxNumSegments > 0;
 
     if (tragedy != null) {
       throw new IllegalStateException("this writer hit an unrecoverable error; cannot merge", tragedy);