add_library cannot create target "CustomControls" because another target with the same name already exists

CMake Error at qtbase/lib/cmake/Qt6Core/Qt6CoreMacros.cmake:2355 (add_library):
add_library cannot create target "CustomControls" because another target
with the same name already exists.  The existing target is a static library
created in source directory
"/home/qt/work/qt/qt5/qtdoc/examples/demos/todolist/imports/CustomControls".
See documentation for policy CMP0002 for more details.
agent:2023/06/21 06:03:55 build.go:402: Call Stack (most recent call first):
qtbase/lib/cmake/Qt6Core/Qt6CoreMacros.cmake:2281 (_qt_internal_add_library)
qtbase/lib/cmake/Qt6Core/Qt6CoreMacros.cmake:2377 (qt6_add_library)
qtdoc/examples/demos/thermostat/imports/CustomControls/CMakeLists.txt:4 (qt_add_library)
agent:2023/06/21 06:03:55 build.go:402: CMake Error at qtbase/lib/cmake/Qt6Qml/Qt6QmlMacros.cmake:2489 (message):
Target CustomControls already has a qmltypes file set.
agent:2023/06/21 06:03:55 build.go:402: Call Stack (most recent call first):
qtbase/lib/cmake/Qt6Qml/Qt6QmlMacros.cmake:540 (_qt_internal_qml_type_registration)
qtbase/lib/cmake/Qt6Qml/Qt6QmlMacros.cmake:716 (qt6_add_qml_module)
qtdoc/examples/demos/thermostat/imports/CustomControls/CMakeLists.txt:5 (qt_add_qml_module)
-- Configuring incomplete, errors occurred!