diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0ebbcb563..e8886a681 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,8 @@ if (NOT (${CMAKE_BUILD_TYPE} MATCHES "Debug"))
                     WORKING_DIRECTORY ${CMAKE_SOURCE_DIR})
 endif ()
 
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -DQT_DEBUG")
+
 # Test architecture
 execute_process(COMMAND dpkg-architecture -qDEB_BUILD_ARCH OUTPUT_VARIABLE ARCHITECTURE RESULT_VARIABLE EXIT_CODE)
 if (${EXIT_CODE} EQUAL 0)