diff --git a/CMakeLists.txt b/CMakeLists.txt
index 274e8b0..45d2064 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,8 +61,8 @@ include( ConfigureChecks.cmake )
 add_definitions( -DHAVE_CONFIG_H )
 
 set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${TQT_CXX_FLAGS}" )
-set( CMAKE_SHARED_LINKER_FLAGS "-Wl,--no-undefined" )
-set( CMAKE_MODULE_LINKER_FLAGS "-Wl,--no-undefined" )
+set( CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--no-undefined" )
+set( CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,--no-undefined" )
 
 
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