diff --git a/etc/mtree/BSD.include.dist b/etc/mtree/BSD.include.dist
index 61cd191b4ace..1041eaf16b33 100644
--- a/etc/mtree/BSD.include.dist
+++ b/etc/mtree/BSD.include.dist
@@ -14,64 +14,64 @@
     bsnmp
     ..
     c++
-	4.2
-	    backward
-	    ..
+        4.2
+            backward
+            ..
             bits
             ..
             debug
             ..
             ext
-		pb_ds
-		    detail
-			pairing_heap_
-			..
-			splay_tree_
-			..
-			list_update_map_
-			..
-			basic_tree_policy
-			..
-			trie_policy
-			..
-			gp_hash_table_map_
-			..
-			tree_policy
-			..
-			binomial_heap_base_
-			..
-			resize_policy
-			..
-			bin_search_tree_
-			..
-			binomial_heap_
-			..
-			thin_heap_
-			..
-			pat_trie_
-			..
-			cc_hash_table_map_
-			..
-			rc_binomial_heap_
-			..
-			left_child_next_sibling_heap_
-			..
-			unordered_iterator
-			..
-			binary_heap_
-			..
-			ov_tree_map_
-			..
-			hash_fn
-			..
-			eq_fn
-			..
-			rb_tree_map_
-			..
-			list_update_policy
-			..
-		    ..
-		..
+                pb_ds
+                    detail
+                        pairing_heap_
+                        ..
+                        splay_tree_
+                        ..
+                        list_update_map_
+                        ..
+                        basic_tree_policy
+                        ..
+                        trie_policy
+                        ..
+                        gp_hash_table_map_
+                        ..
+                        tree_policy
+                        ..
+                        binomial_heap_base_
+                        ..
+                        resize_policy
+                        ..
+                        bin_search_tree_
+                        ..
+                        binomial_heap_
+                        ..
+                        thin_heap_
+                        ..
+                        pat_trie_
+                        ..
+                        cc_hash_table_map_
+                        ..
+                        rc_binomial_heap_
+                        ..
+                        left_child_next_sibling_heap_
+                        ..
+                        unordered_iterator
+                        ..
+                        binary_heap_
+                        ..
+                        ov_tree_map_
+                        ..
+                        hash_fn
+                        ..
+                        eq_fn
+                        ..
+                        rb_tree_map_
+                        ..
+                        list_update_policy
+                        ..
+                    ..
+                ..
             ..
             tr1
             ..