gistfile1.txt

diff --git a/src/spesh/plugin.c b/src/spesh/plugin.c
index bd7f7a031..e651081ad 100644
--- a/src/spesh/plugin.c
+++ b/src/spesh/plugin.c
@@ -285,6 +285,7 @@ typedef struct {
 static void mark_plugin_sr_data(MVMThreadContext *tc, MVMFrame *frame, MVMGCWorklist *worklist) {
     MVMSpeshPluginSpecialReturnData *srd = (MVMSpeshPluginSpecialReturnData *)
         frame->extra->special_return_data;
+    MVM_spesh_plugin_guard_list_mark(tc, tc->prev_plugin_guards, tc->prev_num_plugin_guards, worklist);
     MVM_gc_worklist_add(tc, worklist, &(srd->sf));
     MVM_gc_worklist_add(tc, worklist, &(srd->prev_plugin_guard_args));
 }