CMake: CMAKE_C_STANDARD needs CMake 3.1

CMakeLists.txt

@@ -1,4 +1,4 @@
-CMAKE_MINIMUM_REQUIRED(VERSION 3.0)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.1)
 PROJECT(pi9 VERSION 0.0.1 LANGUAGES C)
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/CMake")
 

lib/chck

@@ -1 +1 @@
-Subproject commit 5ae39c735186070485dc5c2c18c7a111ea744f4b
+Subproject commit 4cb96dd7ab2559196c48f78402a74b4524001e90