diff --git a/scripts/compress-js b/scripts/compress-js
index ea43782eae..445cae49fb 100755
--- a/scripts/compress-js
+++ b/scripts/compress-js
@@ -4,6 +4,7 @@ set -e
 
 for file in `find js -name '*.js' -not -name '*min.js'` ; do
     mkdir -p sources/`dirname $file`
-    mv $file sources/$file
-    java -jar ./scripts/google-javascript-compiler/compiler.jar --js sources/$file --js_output_file $file
+    java -jar ./scripts/google-javascript-compiler/compiler.jar --js $file --js_output_file $file.tmp
+    cp -a $file sources/$file
+    mv $file.tmp $file
 done