diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 3567b7c..41fed3b 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -539,7 +539,6 @@ add_test(record_layer_test record_layer_test)
 
 # rfc3779
 add_executable(rfc3779 rfc3779.c)
-set_source_files_properties(rfc3779.c PROPERTIES COMPILE_FLAGS -D__unused=)
 target_link_libraries(rfc3779 ${OPENSSL_TEST_LIBS})
 add_test(rfc3779 rfc3779)