diff --git a/android/androidmk.go b/android/androidmk.go
index 045cb59..dfc68c4 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -107,6 +107,25 @@
 	a.EntryMap[name] = []string{path.String()}
 }
 
+func (a *AndroidMkEntries) SetOptionalPath(name string, path OptionalPath) {
+	if path.Valid() {
+		a.SetPath(name, path.Path())
+	}
+}
+
+func (a *AndroidMkEntries) AddPath(name string, path Path) {
+	if _, ok := a.EntryMap[name]; !ok {
+		a.entryOrder = append(a.entryOrder, name)
+	}
+	a.EntryMap[name] = append(a.EntryMap[name], path.String())
+}
+
+func (a *AndroidMkEntries) AddOptionalPath(name string, path OptionalPath) {
+	if path.Valid() {
+		a.AddPath(name, path.Path())
+	}
+}
+
 func (a *AndroidMkEntries) SetBoolIfTrue(name string, flag bool) {
 	if flag {
 		if _, ok := a.EntryMap[name]; !ok {
diff --git a/android/paths.go b/android/paths.go
index 066baf2..eef71b7 100644
--- a/android/paths.go
+++ b/android/paths.go
@@ -484,6 +484,10 @@
 	return ret
 }
 
+func CopyOfPaths(paths Paths) Paths {
+	return append(Paths(nil), paths...)
+}
+
 // FirstUniquePaths returns all unique elements of a Paths, keeping the first copy of each.  It
 // modifies the Paths slice contents in place, and returns a subslice of the original slice.
 func FirstUniquePaths(list Paths) Paths {
@@ -494,7 +498,8 @@
 	return firstUniquePathsList(list)
 }
 
-// SortedUniquePaths returns what its name says
+// SortedUniquePaths returns all unique elements of a Paths in sorted order.  It modifies the
+// Paths slice contents in place, and returns a subslice of the original slice.
 func SortedUniquePaths(list Paths) Paths {
 	unique := FirstUniquePaths(list)
 	sort.Slice(unique, func(i, j int) bool {