Missing GC marking in VMArray REPR on Parrot.

Author: jnthn

src/vm/parrot/6model/reprs/VMArray.c

@@ -332,6 +332,23 @@ static void gc_free(PARROT_INTERP, PMC *obj) {
     mem_sys_free(instance);
 }
 
+/* This Parrot-specific addition to the API is used to mark a repr's
+ * per-type data. */
+static void gc_mark_repr_data(PARROT_INTERP, STable *st) {
+    VMArrayREPRData *repr_data = (VMArrayREPRData *) st->REPR_data;
+    if (repr_data)
+        Parrot_gc_mark_PMC_alive(interp, repr_data->elem_type);
+}
+
+/* This Parrot-specific addition to the API is used to free a repr instance. */
+static void gc_free_repr_data(PARROT_INTERP, STable *st) {
+    if (st->REPR_data) {
+        free(st->REPR_data);
+        st->REPR_data = NULL;
+    }
+}
+
+
 static void at_pos_native(PARROT_INTERP, STable *st, void *data, INTVAL index, NativeValue *value) {
     VMArrayBody *body = (VMArrayBody *) data;
     VMArrayREPRData *repr_data = (VMArrayREPRData *) st->REPR_data;
@@ -518,6 +535,8 @@ REPROps * VMArray_initialize(PARROT_INTERP) {
     this_repr->serialize_repr_data = serialize_repr_data;
     this_repr->deserialize_repr_data = deserialize_repr_data;
     this_repr->gc_free = gc_free;
+    this_repr->gc_mark_repr_data = gc_mark_repr_data;
+    this_repr->gc_free_repr_data = gc_free_repr_data;
     this_repr->get_storage_spec = get_storage_spec;
     this_repr->pos_funcs = mem_allocate_zeroed_typed(REPROps_Positional);
     this_repr->pos_funcs->at_pos_native = at_pos_native;