diff --git a/packager/src/lib/GlobalTransformCache.js b/packager/src/lib/GlobalTransformCache.js
index 12deb44f8..5572ce1a2 100644
--- a/packager/src/lib/GlobalTransformCache.js
+++ b/packager/src/lib/GlobalTransformCache.js
@@ -408,8 +408,9 @@ class OptionsHasher {
   }
 
   relativizeFilePaths(filePaths: Array<string>): Array<string> {
-    return filePaths.map(this.relativizeFilePath);
+    return filePaths.map(this.relativizeFilePath.bind(this));
   }
+
   relativizeFilePath(filePath: string): string {
     return path.relative(this._rootPath, filePath);
   }