error: implicit instantiation of undefined template 'TestNamespace::QVarLengthArray<double, 16>'

src/quickvectorimage/CMakeFiles/QuickVectorImageGeneratorPrivate.dir/generator/qquickgenerator.cpp.o.d -o src/quickvectorimage/CMakeFiles/QuickVectorImageGeneratorPrivate.dir/generator/qquickgenerator.cpp.o -c /Users/qt/work/qt/qtdeclarative/src/quickvectorimage/generator/qquickgenerator.cpp
In file included from /Users/qt/work/qt/qtdeclarative/src/quickvectorimage/generator/qquickgenerator.cpp:5:
In file included from /Users/qt/work/qt/qtdeclarative/src/quickvectorimage/generator/qsvgvisitorimpl_p.h:18:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgvisitor_p.h:18:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgtinydocument_p.h:29:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvganimator_p.h:20:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgabstractanimation_p.h:19:
/Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvganimatedproperty_p.h:102:36: error: implicit instantiation of undefined template 'TestNamespace::QVarLengthArray<double, 16>'
        QVarLengthArray<qreal, 16> values;
                                   ^
/Users/qt/work/install/include/QtCore/qcontainerfwd.h:35:82: note: template is declared here
template <typename T, qsizetype Prealloc = QVarLengthArrayDefaultPrealloc> class QVarLengthArray;
                                                                                 ^
1 error generated.
Sccache command failed, re-try calling build tool directly
In file included from /Users/qt/work/qt/qtdeclarative/src/quickvectorimage/generator/qquickgenerator.cpp:5:
In file included from /Users/qt/work/qt/qtdeclarative/src/quickvectorimage/generator/qsvgvisitorimpl_p.h:18:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgvisitor_p.h:18:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgtinydocument_p.h:29:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvganimator_p.h:20:
In file included from /Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvgabstractanimation_p.h:19:
/Users/qt/work/install/include/QtSvg/6.10.0/QtSvg/private/qsvganimatedproperty_p.h:102:36: error: implicit instantiation of undefined template 'TestNamespace::QVarLengthArray<double, 16>'
        QVarLengthArray<qreal, 16> values;
                                   ^
/Users/qt/work/install/include/QtCore/qcontainerfwd.h:35:82: note: template is declared here
template <typename T, qsizetype Prealloc = QVarLengthArrayDefaultPrealloc> class QVarLengthArray;
                                                                                 ^
1 error generated.