diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b2f669..9859564 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,7 @@ set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-set(CMAKE_C_STANDARD 11)
+set(CMAKE_C_STANDARD 99)
 set(CMAKE_C_STANDARD_REQUIRED ON)
 
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)