diff --git a/src/wayland/CMakeLists.txt b/src/wayland/CMakeLists.txt
index 55358e2b8c..c15e8b434d 100644
--- a/src/wayland/CMakeLists.txt
+++ b/src/wayland/CMakeLists.txt
@@ -5,178 +5,177 @@ if (BUILD_TESTING)
     add_subdirectory(tests)
 endif()
 
-set(WaylandProtocols_xml_SOURCES)
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+# CMake has a known bug where target_source() doesn't work as expected with files generated
+# in a directory other than the one where the target is defined. It should be fixed in 3.20.
+add_library(WaylandProtocols_xml OBJECT)
+target_link_libraries(WaylandProtocols_xml Qt::Core Wayland::Server)
+target_link_libraries(kwin WaylandProtocols_xml)
+
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${Wayland_DATADIR}/wayland.xml
     BASENAME wayland
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-device-v2.xml
     BASENAME kde-output-device-v2
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-primary-output-v1.xml
     BASENAME kde-primary-output-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-management-v2.xml
     BASENAME kde-output-management-v2
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/plasma-shell.xml
     BASENAME plasma-shell
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/plasma-virtual-desktop.xml
     BASENAME org-kde-plasma-virtual-desktop
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/plasma-window-management.xml
     BASENAME plasma-window-management
 )
-ecm_add_wayland_server_protocol(WaylandProtocols_xml_SOURCES
+ecm_add_wayland_server_protocol(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/surface-extension.xml
     BASENAME qt-surface-extension
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/idle.xml
     BASENAME idle
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/fake-input.xml
     BASENAME fake-input
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/shadow.xml
     BASENAME shadow
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/dpms.xml
     BASENAME dpms
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/blur.xml
     BASENAME blur
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/contrast.xml
     BASENAME contrast
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/relative-pointer/relative-pointer-unstable-v1.xml
     BASENAME relative-pointer-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/slide.xml
     BASENAME slide
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/server-decoration.xml
     BASENAME server-decoration
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/text-input/text-input-unstable-v1.xml
     BASENAME text-input-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/text-input-unstable-v2.xml
     BASENAME text-input-unstable-v2
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/text-input/text-input-unstable-v3.xml
     BASENAME text-input-unstable-v3
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/pointer-gestures/pointer-gestures-unstable-v1.xml
     BASENAME pointer-gestures-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/pointer-constraints/pointer-constraints-unstable-v1.xml
     BASENAME pointer-constraints-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/xdg-foreign/xdg-foreign-unstable-v2.xml
     BASENAME xdg-foreign-unstable-v2
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/idle-inhibit/idle-inhibit-unstable-v1.xml
     BASENAME idle-inhibit-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/appmenu.xml
     BASENAME appmenu
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/server-decoration-palette.xml
     BASENAME server-decoration-palette
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/xdg-output/xdg-output-unstable-v1.xml
     BASENAME xdg-output-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/stable/xdg-shell/xdg-shell.xml
     BASENAME xdg-shell
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/xdg-decoration/xdg-decoration-unstable-v1.xml
     BASENAME xdg-decoration-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/keystate.xml
     BASENAME keystate
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml
     BASENAME linux-dmabuf-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/tablet/tablet-unstable-v2.xml
     BASENAME tablet-unstable-v2
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PROJECT_SOURCE_DIR}/src/wayland/protocols/wlr-data-control-unstable-v1.xml
     BASENAME wlr-data-control-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PROJECT_SOURCE_DIR}/src/wayland/protocols/wlr-layer-shell-unstable-v1.xml
     BASENAME wlr-layer-shell-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/keyboard-shortcuts-inhibit/keyboard-shortcuts-inhibit-unstable-v1.xml
     BASENAME keyboard-shortcuts-inhibit-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/stable/viewporter/viewporter.xml
     BASENAME viewporter
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/primary-selection/primary-selection-unstable-v1.xml
     BASENAME wp-primary-selection-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/screencast.xml
     BASENAME zkde-screencast-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/unstable/input-method/input-method-unstable-v1.xml
     BASENAME input-method-unstable-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/staging/xdg-activation/xdg-activation-v1.xml
     BASENAME xdg-activation-v1
 )
-ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml_SOURCES
+ecm_add_qtwayland_server_protocol_kde(WaylandProtocols_xml
     PROTOCOL ${WaylandProtocols_DATADIR}/staging/drm-lease/drm-lease-v1.xml
     BASENAME drm-lease-v1
 )
 
-# CMake has a known bug where target_source() doesn't work as expected with files generated
-# in a directory other than the one where the target is defined. It should be fixed in 3.20.
-add_library(WaylandProtocols_xml OBJECT ${WaylandProtocols_xml_SOURCES})
-target_link_libraries(WaylandProtocols_xml Qt::Core Wayland::Server)
-target_link_libraries(kwin WaylandProtocols_xml)
-
 target_sources(kwin PRIVATE
     abstract_data_source.cpp
     abstract_drop_handler.cpp
diff --git a/src/wayland/tools/CMakeLists.txt b/src/wayland/tools/CMakeLists.txt
index 5eea6e49b6..c7c6850a5d 100644
--- a/src/wayland/tools/CMakeLists.txt
+++ b/src/wayland/tools/CMakeLists.txt
@@ -2,7 +2,7 @@ remove_definitions(-DQT_NO_CAST_FROM_ASCII)
 add_executable(qtwaylandscanner_kde qtwaylandscanner.cpp)
 target_link_libraries(qtwaylandscanner_kde Qt::Core)
 
-function(ecm_add_qtwayland_server_protocol_kde out_var)
+function(ecm_add_qtwayland_server_protocol_kde target)
     # Parse arguments
     set(oneValueArgs PROTOCOL BASENAME PREFIX)
     cmake_parse_arguments(ARGS "" "${oneValueArgs}" "" ${ARGN})
@@ -15,7 +15,7 @@ function(ecm_add_qtwayland_server_protocol_kde out_var)
 
 
     find_package(WaylandScanner REQUIRED QUIET)
-    ecm_add_wayland_server_protocol(${out_var}
+    ecm_add_wayland_server_protocol(${target}
                                     PROTOCOL ${ARGS_PROTOCOL}
                                     BASENAME ${ARGS_BASENAME})
 
@@ -35,6 +35,5 @@ function(ecm_add_qtwayland_server_protocol_kde out_var)
 
     set_property(SOURCE ${_header} ${_code} PROPERTY SKIP_AUTOMOC ON)
 
-    list(APPEND ${out_var} "${_code}")
-    set(${out_var} ${${out_var}} PARENT_SCOPE)
+    target_sources(${target} PRIVATE "${_code}")
 endfunction()