diff --git a/src/c/hydra-eval-jobs.cc b/src/c/hydra-eval-jobs.cc
index 7f79a513..22775840 100644
--- a/src/c/hydra-eval-jobs.cc
+++ b/src/c/hydra-eval-jobs.cc
@@ -178,7 +178,7 @@ static void findJobsWrapped(EvalState & state, XMLWriter & doc,
             Bindings());
     }
 
-    else if (v.type = tNull) {
+    else if (v.type == tNull) {
         // allow null values, meaning 'do nothing'
     }