diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java
index 95e1d2143..f07c24efc 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java
@@ -657,8 +657,7 @@ void writeTo(File dir, OutputStream os) throws IOException {
 
 		// Write the individual file entries.
 
-		final int smudge_s;
-		final int smudge_ns;
+		Instant smudge;
 		if (myLock != null) {
 			// For new files we need to smudge the index entry
 			// if they have been modified "now". Ideally we'd
@@ -666,12 +665,10 @@ void writeTo(File dir, OutputStream os) throws IOException {
 			// so we use the current timestamp as a approximation.
 			myLock.createCommitSnapshot();
 			snapshot = myLock.getCommitSnapshot();
-			smudge_s = (int) (snapshot.lastModifiedInstant().getEpochSecond());
-			smudge_ns = snapshot.lastModifiedInstant().getNano();
+			smudge = snapshot.lastModifiedInstant();
 		} else {
 			// Used in unit tests only
-			smudge_ns = 0;
-			smudge_s = 0;
+			smudge = Instant.EPOCH;
 		}
 
 		// Check if tree is non-null here since calling updateSmudgedEntries
@@ -683,8 +680,9 @@ void writeTo(File dir, OutputStream os) throws IOException {
 
 		for (int i = 0; i < entryCnt; i++) {
 			final DirCacheEntry e = sortedEntries[i];
-			if (e.mightBeRacilyClean(smudge_s, smudge_ns))
+			if (e.mightBeRacilyClean(smudge)) {
 				e.smudgeRacilyClean();
+			}
 			e.write(dos);
 		}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheEntry.java b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheEntry.java
index d4db15ce9..0e91f0d74 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheEntry.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheEntry.java
@@ -378,7 +378,7 @@ public final boolean mightBeRacilyClean(Instant smudge) {
 		//
 		final int base = infoOffset + P_MTIME;
 		final int mtime = NB.decodeInt32(info, base);
-		if (smudge.getEpochSecond() == mtime) {
+		if ((int) smudge.getEpochSecond() == mtime) {
 			return smudge.getNano() <= NB.decodeInt32(info, base + 4);
 		}
 		return false;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
index d432c9445..4f3eb05b1 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
@@ -412,6 +412,9 @@ public long getLastModified() {
 			return attributes.getLastModifiedInstant().toEpochMilli();
 		}
 
+		/**
+		 * @since 5.1.9
+		 */
 		@Override
 		public Instant getLastModifiedInstant() {
 			return attributes.getLastModifiedInstant();