--- old/src/share/vm/gc/g1/g1CollectorPolicy.cpp	2015-11-24 10:07:43.245900675 +0100
+++ new/src/share/vm/gc/g1/g1CollectorPolicy.cpp	2015-11-24 10:07:43.133896341 +0100
@@ -1647,9 +1647,9 @@
       ergo_verbose0(ErgoConcCycles,
                     "initiate concurrent cycle",
                     ergo_format_reason("concurrent cycle initiation requested"));
-    } else if (_g1->user_requested_concurrent_full_gc(_g1->gc_cause())) {
-      // Initiate a user requested initial mark and update the collector state to
-      // reflect this.
+    } else if (_g1->is_user_requested_concurrent_full_gc(_g1->gc_cause())) {
+      // Initiate a user requested initial mark. An initial mark must be young only
+      // GC, so the collector state must be updated to reflect this.
       collector_state()->set_gcs_are_young(true);
       collector_state()->set_last_young_gc(false);