diff --git a/android/module.go b/android/module.go
index 1c36279..394d0f4 100644
--- a/android/module.go
+++ b/android/module.go
@@ -18,7 +18,6 @@
 	"fmt"
 	"path"
 	"path/filepath"
-	"sort"
 	"strings"
 	"text/scanner"
 
@@ -1628,17 +1627,8 @@
 		return
 	}
 
-	sortedKeys := func(m map[string]Paths) []string {
-		s := make([]string, 0, len(m))
-		for k := range m {
-			s = append(s, k)
-		}
-		sort.Strings(s)
-		return s
-	}
-
 	// Ensure ancestor directories are in modulesInDir
-	dirs := sortedKeys(modulesInDir)
+	dirs := SortedStringKeys(modulesInDir)
 	for _, dir := range dirs {
 		dir := parentDir(dir)
 		for dir != "." && dir != "/" {
@@ -1651,7 +1641,6 @@
 	}
 
 	// Make directories build their direct subdirectories
-	dirs = sortedKeys(modulesInDir)
 	for _, dir := range dirs {
 		p := parentDir(dir)
 		if p != "." && p != "/" {
@@ -1708,8 +1697,7 @@
 	}
 
 	// Wrap those into host|host-cross|target phony rules
-	osClasses := sortedKeys(osClass)
-	for _, class := range osClasses {
+	for _, class := range SortedStringKeys(osClass) {
 		ctx.Build(pctx, BuildParams{
 			Rule:      blueprint.Phony,
 			Output:    PathForPhony(ctx, class),
diff --git a/android/util.go b/android/util.go
index f7a3437..3b8bc78 100644
--- a/android/util.go
+++ b/android/util.go
@@ -16,6 +16,7 @@
 
 import (
 	"fmt"
+	"reflect"
 	"regexp"
 	"runtime"
 	"sort"
@@ -77,10 +78,15 @@
 	return string(ret)
 }
 
-func sortedKeys(m map[string][]string) []string {
-	s := make([]string, 0, len(m))
-	for k := range m {
-		s = append(s, k)
+func SortedStringKeys(m interface{}) []string {
+	v := reflect.ValueOf(m)
+	if v.Kind() != reflect.Map {
+		panic(fmt.Sprintf("%#v is not a map", m))
+	}
+	keys := v.MapKeys()
+	s := make([]string, 0, len(keys))
+	for _, key := range keys {
+		s = append(s, key.String())
 	}
 	sort.Strings(s)
 	return s