!contains(QMAKE_EXTRA_TARGETS, docs) {
    contains(TEMPLATE, subdirs) {
        prepare_docs {
            prepareRecursiveTarget(prepare_docs)
            prepareRecursiveTarget(generate_docs)
            html_docs.commands = $(MAKE) -f $(MAKEFILE) prepare_docs && $(MAKE) -f $(MAKEFILE) generate_docs
        } else {
            prepareRecursiveTarget(html_docs)
        }
        prepareRecursiveTarget(qch_docs)
        prepareRecursiveTarget(docs)
    } else {
        # apps and libs only generate docs if QMAKE_DOCS is set
        !isEmpty(QMAKE_DOCS) {
            !exists($$QMAKE_DOCS):error("Cannot find documentation specification file $$QMAKE_DOCS")
            qtPrepareTool(QDOC, qdoc)
            for(index, QMAKE_DOCS_INDEX):QDOC_INDEX += -indexdir $$index
            !isEmpty(QMAKE_DOCS_OUTPUTDIR):QMAKE_DOCS_OPTIONS += -outputdir $$QMAKE_DOCS_OUTPUTDIR
            !isEmpty(QMAKE_DOCS_INSTALLDIR):QMAKE_DOCS_OPTIONS += -installdir $$QMAKE_DOCS_INSTALLDIR
            doc_command = $$QDOC $$QMAKE_DOCS_OPTIONS $$QDOC_INDEX $$QMAKE_DOCS
            prepare_docs {
                prepare_docs.commands += $$doc_command -prepare -no-link-errors
                generate_docs.commands += $$doc_command -generate
                html_docs.depends += generate_docs
            } else {
                html_docs.commands += $$doc_command
            }

            qtPrepareTool(QHELPGENERATOR, qhelpgenerator)
            isEmpty(QMAKE_DOCS_TARGET): QMAKE_DOCS_TARGET = $$basename(QMAKE_DOCS_OUTPUTDIR)
            qch_docs.commands = $$QHELPGENERATOR $$QMAKE_DOCS_OUTPUTDIR/$${QMAKE_DOCS_TARGET}.qhp -o $$QMAKE_DOCS_BASE_OUTDIR/$${QMAKE_DOCS_TARGET}.qch
        }
    }
    docs.commands = $(MAKE) -f $(MAKEFILE) html_docs && $(MAKE) -f $(MAKEFILE) qch_docs
    QMAKE_EXTRA_TARGETS += html_docs qch_docs docs
    prepare_docs: QMAKE_EXTRA_TARGETS += prepare_docs generate_docs
}

!contains(QMAKE_EXTRA_TARGETS, install_docs) {
    contains(TEMPLATE, subdirs) {
        prepareRecursiveTarget(install_html_docs)
        prepareRecursiveTarget(uninstall_html_docs)
        prepareRecursiveTarget(install_qch_docs)
        prepareRecursiveTarget(uninstall_qch_docs)
        prepareRecursiveTarget(install_docs)
        prepareRecursiveTarget(uninstall_docs)
    }
    QMAKE_EXTRA_TARGETS += \
        install_html_docs uninstall_html_docs \
        install_qch_docs uninstall_qch_docs \
        install_docs uninstall_docs
}