diff --git a/diff-lib.c b/diff-lib.c
index 9520773..52dbac3 100644
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -641,6 +641,21 @@
 	show_modified(revs, tree, idx, 1, cached, match_missing);
 }
 
+static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+	int len = ce_namelen(ce);
+	const struct index_state *index = o->src_index;
+
+	while (o->pos < index->cache_nr) {
+		struct cache_entry *next = index->cache[o->pos];
+		if (len != ce_namelen(next))
+			break;
+		if (memcmp(ce->name, next->name, len))
+			break;
+		o->pos++;
+	}
+}
+
 /*
  * The unpack_trees() interface is designed for merging, so
  * the different source entries are designed primarily for
@@ -662,6 +677,9 @@
 	struct cache_entry *tree = src[1];
 	struct rev_info *revs = o->unpack_data;
 
+	if (idx && ce_stage(idx))
+		skip_same_name(idx, o);
+
 	/*
 	 * Unpack-trees generates a DF/conflict entry if
 	 * there was a directory in the index and a tree