--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -4,9 +4,9 @@ include_directories(${CHECK_INCLUDE_DIRS
 
 # Compiler flags:
 if(APPLE)
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O0 -g -Wl,-undefined,dynamic_lookup")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wl,-undefined,dynamic_lookup")
 else()
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O0 -g -Wl,--unresolved-symbols=ignore-in-object-files")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wl,--unresolved-symbols=ignore-in-object-files")
 endif()
 
 set(TEST_PATH ${CMAKE_CURRENT_BINARY_DIR})