diff --git a/js/src/gc/Marking.cpp b/js/src/gc/Marking.cpp
index 38993aa79ead..9ef1ab9f50f4 100644
--- a/js/src/gc/Marking.cpp
+++ b/js/src/gc/Marking.cpp
@@ -1162,7 +1162,7 @@ GCMarker::processMarkStackTop(SliceBudget &budget)
             JS_COMPARTMENT_ASSERT_STR(runtime, str);
             JS_ASSERT(str->compartment() == runtime->atomsCompartment ||
                       str->compartment() == obj->compartment());
-    if (str->markIfUnmarked())
+            if (str->markIfUnmarked())
                 ScanString(this, str);
         } else if (v.isObject()) {
             JSObject *obj2 = &v.toObject();