diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 9f2cb74..9c79747 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -15,6 +15,11 @@ endif()
 option(TURTLE_WERROR "Treat warnings as errors" ON)
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
   target_compile_options(TurtleTestMain INTERFACE -Wall -Wextra -pedantic -Wno-long-long)
+  include(CheckCXXCompilerFlag)
+  check_cxx_compiler_flag(-Wunused-function TURTLE_CXX_UNUSED_FUNCTION)
+  if(TURTLE_CXX_UNUSED_FUNCTION)
+    target_compile_options(TurtleTestMain INTERFACE -Wno-unused-function)
+  endif()
   if(TURTLE_WERROR)
     target_compile_options(TurtleTestMain INTERFACE -Werror)
   endif()