diff --git a/include/picrin.h b/include/picrin.h
index 6c18fe27..0d250f7b 100644
--- a/include/picrin.h
+++ b/include/picrin.h
@@ -121,7 +121,7 @@ struct pic_object *pic_obj_alloc_unsafe(pic_state *, size_t, enum pic_tt);
 void pic_free(pic_state *, void *);
 
 void pic_gc_run(pic_state *);
-void pic_gc_protect(pic_state *, pic_value);
+pic_value pic_gc_protect(pic_state *, pic_value);
 int pic_gc_arena_preserve(pic_state *);
 void pic_gc_arena_restore(pic_state *, int);
 
diff --git a/src/gc.c b/src/gc.c
index 97b45195..2d42ade6 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -183,17 +183,19 @@ gc_protect(pic_state *pic, struct pic_object *obj)
   pic->arena[pic->arena_idx++] = obj;
 }
 
-void
+pic_value
 pic_gc_protect(pic_state *pic, pic_value v)
 {
   struct pic_object *obj;
 
   if (pic_vtype(v) != PIC_VTYPE_HEAP) {
-    return;
+    return v;
   }
   obj = pic_obj_ptr(v);
 
   gc_protect(pic, obj);
+
+  return v;
 }
 
 int