如何在不使用Qt模块的qmake项目中使用moc？

QT += core

class MyClass : public QObject
{
    Q_OBJECT
    // ...
};

HEADERS += MyClass.h

moc_headers.target = moc
moc_headers.commands = $$[QT_INSTALL_BINS]/moc $$moc_headers.input -o $$moc_headers.output
moc_headers.depends = $$moc_headers.input
moc_headers.input = HEADERS
moc_headers.output = $$OUT_PWD/moc_$$basename($$moc_headers.input).cpp
QMAKE_EXTRA_COMPILERS += moc_headers

SOURCES += $$OUT_PWD/moc_$$basename($$HEADERS).cpp