diff --git a/README_gc.md b/README_gc.md
index 113534c..765a8b6 100644
--- a/README_gc.md
+++ b/README_gc.md
@@ -34,3 +34,4 @@ Golang 编程：245386165
 |2015-11-25|13.10 性能调试：分析并优化 Go 程序
 |2015-12-10|15.0 15.1 15.2
 |2015-12-12|15.3
+|2015-12-22|15.4