diff --git a/demo/viewer/CMakeLists.txt b/demo/viewer/CMakeLists.txt
index 599255d9f..8d12c33e9 100644
--- a/demo/viewer/CMakeLists.txt
+++ b/demo/viewer/CMakeLists.txt
@@ -46,7 +46,7 @@ install(TARGETS mapnik-viewer
 )
 
 
-if(WIN32)
+if(ADDITIONAL_LIBARIES_PATHS AND WIN32)
     include(CopyDllsForDebug)
     add_custom_command(TARGET mapnik-viewer POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:mapnik::mapnik>" ${CMAKE_CURRENT_BINARY_DIR})
     copy_dlls_for_debug(mapnik-viewer \"\" \"${ADDITIONAL_LIBARIES_PATHS}\")
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 05cdfbe99..37947404b 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -168,7 +168,7 @@ include(CTest)
 include(${catch2_SOURCE_DIR}/contrib/Catch.cmake)
 include(${catch2_SOURCE_DIR}/contrib/ParseAndAddCatchTests.cmake)
 
-if(WIN32)
+if(ADDITIONAL_LIBARIES_PATHS AND WIN32)
     include(CopyDllsForDebug)
     add_custom_command(TARGET mapnik-test-unit  POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:mapnik::mapnik>" ${CMAKE_CURRENT_BINARY_DIR})
     set(APPS mapnik-test-unit agg_rasterizer_integer_overflow_test datasource_registration_test font_registration_test map_xml_test mapnik-test-visual)