--- a/src/hotspot/share/gc/shenandoah/shenandoahCodeRoots.cpp	Mon Nov 25 12:30:24 2019 +0100
+++ b/src/hotspot/share/gc/shenandoah/shenandoahCodeRoots.cpp	Mon Nov 25 12:31:39 2019 +0100
@@ -264,7 +264,7 @@
 
   size_t max = (size_t)list->length();
   while (_claimed < max) {
-    size_t cur = Atomic::add(stride, &_claimed) - stride;
+    size_t cur = Atomic::add(&_claimed, stride) - stride;
     size_t start = cur;
     size_t end = MIN2(cur + stride, max);
     if (start >= max) break;