diff --git a/bin/bitbake-worker b/bin/bitbake-worker
index aa14ef191..0db1531e0 100755
--- a/bin/bitbake-worker
+++ b/bin/bitbake-worker
@@ -290,7 +290,7 @@ def fork_off_task(cfg, data, databuilder, workerdata, extraconfigdata, runtask):
 
                 # exported_vars() returns a generator which *cannot* be passed to os.environ.update() 
                 # successfully. We also need to unset anything from the environment which shouldn't be there 
-                exports = bb.data.exported_vars(the_data)
+                exports = list(bb.data.exported_vars(the_data))
 
                 bb.utils.empty_environment()
                 for e, v in exports: