diff --git a/talk/build/isolate.gypi b/talk/build/isolate.gypi
index d1ff291efd..24f7ea1edc 100644
--- a/talk/build/isolate.gypi
+++ b/talk/build/isolate.gypi
@@ -113,6 +113,7 @@
 
         # Path variables are used to replace file paths when loading a .isolate
         # file
+        '--path-variable', 'DEPTH', '<(DEPTH)',
         '--path-variable', 'PRODUCT_DIR', '<(PRODUCT_DIR) ',
 
         '--config-variable', 'OS=<(OS)',