diff --git a/builtin/stash.c b/builtin/stash.c
index 2e2e40823b77f9..79fec5612edb6c 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -403,7 +403,7 @@ static int restore_untracked(struct object_id *u_tree)
 
 	child_process_init(&cp);
 	cp.git_cmd = 1;
-	strvec_pushl(&cp.args, "checkout-index", "--all", NULL);
+	strvec_pushl(&cp.args, "checkout-index", "--all", "-f", NULL);
 	strvec_pushf(&cp.env, "GIT_INDEX_FILE=%s",
 		     stash_index_path.buf);
 
diff --git a/sparse-index.c b/sparse-index.c
index c264766dd632d9..485b3972836d7d 100644
--- a/sparse-index.c
+++ b/sparse-index.c
@@ -375,6 +375,10 @@ void expand_index(struct index_state *istate, struct pattern_list *pl)
 	full = xcalloc(1, sizeof(struct index_state));
 	memcpy(full, istate, sizeof(struct index_state));
 
+	full->name_hash_initialized = 0;
+	memset(&full->name_hash, 0, sizeof(full->name_hash));
+	memset(&full->dir_hash, 0, sizeof(full->dir_hash));
+
 	/*
 	 * This slightly-misnamed 'full' index might still be sparse if we
 	 * are only modifying the list of sparse directories. This hinges
@@ -433,9 +437,15 @@ void expand_index(struct index_state *istate, struct pattern_list *pl)
 	}
 
 	/* Copy back into original index. */
+	if (istate->name_hash_initialized) {
+		hashmap_clear(&istate->name_hash);
+		hashmap_clear(&istate->dir_hash);
+	}
+
 	istate->name_hash_initialized = full->name_hash_initialized;
 	memcpy(&istate->name_hash, &full->name_hash, sizeof(full->name_hash));
 	memcpy(&istate->dir_hash, &full->dir_hash, sizeof(full->dir_hash));
+
 	istate->sparse_index = pl ? INDEX_PARTIALLY_SPARSE : INDEX_EXPANDED;
 	free(istate->cache);
 	istate->cache = full->cache;