Set C standard to 17

indra/CMakeLists.txt

@@ -13,6 +13,7 @@ project(${ROOT_PROJECT_NAME})
 
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake")
 
+set(CMAKE_C_STANDARD 17)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_VISIBILITY_PRESET hidden)