diff --git a/grpc.def b/grpc.def
index 09a94a6..552bf75 100644
--- a/grpc.def
+++ b/grpc.def
@@ -220,6 +220,8 @@
     gpr_avl_add
     gpr_avl_remove
     gpr_avl_get
+    gpr_avl_maybe_get
+    gpr_avl_is_empty
     gpr_cmdline_create
     gpr_cmdline_add_int
     gpr_cmdline_add_flag