diff --git a/src/libs/utils/environment.cpp b/src/libs/utils/environment.cpp
index 298987ee557..9ff5b4be87d 100644
--- a/src/libs/utils/environment.cpp
+++ b/src/libs/utils/environment.cpp
@@ -376,7 +376,7 @@ QList<EnvironmentItem> Environment::diff(const Environment &other) const
         if (thisIt == constEnd()) {
             result.append(EnvironmentItem(otherIt.key(), otherIt.value()));
             ++otherIt;
-        } else if (otherIt == constEnd()) {
+        } else if (otherIt == other.constEnd()) {
             EnvironmentItem item(thisIt.key(), QString());
             item.unset = true;
             result.append(item);