diff --git a/CMakeLists.txt b/CMakeLists.txt
index 558aedf75..6f1e78087 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,7 +16,7 @@ endif(CMAKE_COMPILER_IS_GNUCC)
 if(CMAKE_COMPILER_IS_CLANG)
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O2 -Wall -Wextra -W -Wdeclaration-after-statement")
   set(CMAKE_C_FLAGS_DEBUG "-g3 -O0")
-  set(CMAKE_C_FLAGS_CHECK "${CMAKE_C_FLAGS} -Werror -Wpointer-arith -Wwrite-strings -Wdocumentation")
+  set(CMAKE_C_FLAGS_CHECK "${CMAKE_C_FLAGS} -Werror -Wpointer-arith -Wwrite-strings -Wdocumentation -Wno-unused-function")
 endif(CMAKE_COMPILER_IS_CLANG)
 
 set(CMAKE_BUILD_TYPE ${CMAKE_BUILD_TYPE}