diff --git a/devel/glib20/Makefile b/devel/glib20/Makefile
index f643570a17bd..33bb3c4993fc 100644
--- a/devel/glib20/Makefile
+++ b/devel/glib20/Makefile
@@ -1,121 +1,135 @@
 # Created by: Vanilla I. Shu <vanilla@FreeBSD.org>
 
 PORTNAME=	glib
 DISTVERSION=	2.70.4
-PORTREVISION=	4
+PORTREVISION=	5
 PORTEPOCH=	2
 CATEGORIES=	devel
 MASTER_SITES=	GNOME
 DIST_SUBDIR=	gnome
 
 MAINTAINER=	desktop@FreeBSD.org
 COMMENT=	Some useful routines of C programming (current stable version)
 
 LICENSE=	LGPL20
 
 LIB_DEPENDS=	libffi.so:devel/libffi \
 		libpcre.so:devel/pcre
 
 # iconv:wchar_t - our iconv in base doesn't support utf-8 -> wchar_t (boooo)
 # (wchar_t is used by glibmm, rawtherapee triggered this)
 USES=		compiler:c11 cpe gettext gnome iconv:wchar_t localbase:ldflags \
 		meson perl5 pkgconfig python:3.6+ tar:xz trigger
 TRIGGERS=	gio-modules glib-schemas
 USE_LDCONFIG=	yes
 USE_PERL5=	build
 USE_PYTHON=	py3kplist
 MESON_ARGS=	-Db_lundef=false \
 		-Ddefault_library=both \
 		-Dinstalled_tests=false \
 		-Dlibmount=disabled \
 		-Dlocalstatedir=/var \
 		-Dselinux=disabled \
 		-Dxattr=false
 BINARY_ALIAS=	python3=${PYTHON_CMD}
 PORTSCOUT=	limitw:1,even
 CPE_VENDOR=	gnome
 
 CONFLICTS_INSTALL=	p5-Giovanni
 
 _LIBVERSION=	0.7000.4
 PLIST_SUB=	LIBVERSION=${_LIBVERSION}
 
 OPTIONS_DEFINE=		DEBUG DOCS FAM_ALTBACKEND MANPAGES NLS TEST
 OPTIONS_DEFAULT=	MANPAGES
 OPTIONS_SUB=		yes
 
 DOCS_BUILD_DEPENDS=	gtk-doc>0:textproc/gtk-doc
 DOCS_IMPLIES=		TEST
 DOCS_MESON_TRUE=	gtk_doc
 
 FAM_ALTBACKEND_DESC=	Alternate file monitor backend
 
 MANPAGES_BUILD_DEPENDS=	docbook-xml>4.1.2:textproc/docbook-xml \
 			docbook-xsl>0:textproc/docbook-xsl
 MANPAGES_USE=		GNOME=libxslt:build
 MANPAGES_MESON_TRUE=	man
 
 TEST_BUILD_DEPENDS=	dbus-daemon:devel/dbus
 TEST_MESON_TRUE=	tests
 
 .include <bsd.port.pre.mk>
 
 # doesn't build yet
 MESON_ARGS+=	-Ddtrace=false
 
 .if empty(ICONV_LIB)
 # native?
 MESON_ARGS+=	-Diconv=libc
 .else
 MESON_ARGS+=	-Diconv=external
 .endif
 
 pre-configure-FAM_ALTBACKEND-on:
 	@${REINPLACE_CMD} -e 's|kqueue-helper.c|kqueue_fnm.c|g ; \
 		s|.*kqueue-missing.c.*||g ; \
 		s|.*dep-list.c.*||g' \
 		${WRKSRC}/gio/kqueue/meson.build
 	@${CP} -f ${FILESDIR}/gkqueuefilemonitor.c ${WRKSRC}/gio/kqueue/gkqueuefilemonitor.c
 	@${CP} ${FILESDIR}/kqueue_fnm.c ${WRKSRC}/gio/kqueue/kqueue_fnm.c
 	@${CP} ${FILESDIR}/kqueue_fnm.h ${WRKSRC}/gio/kqueue/kqueue_fnm.h
 
+# The generation of GIO documentation depends on a types-document
+# generated as part of the dbus-object-manager example. With an
+# embarrassingly parallel build, failures like this can happen:
+#
+# Building documentation for gdbus-object-manager-example
+# ERROR: Error in gtkdoc helper script:
+# FileNotFoundError: [Errno 2] No such file or directory: '_build/docs/reference/gio/gdbus-object-manager-example/gdbus-object-manager-example.types'
+#
+# Meson does not seem to provide a way to express that dependency.
+#
+# Hack it into the generated ninja build instead.
+post-configure-DOCS-on:
+	@${REINPLACE_CMD} -e '\+^build docs/reference/gio/gdbus-object-manager-example/gdbus-object-manager-example-decl.txt:+s+$$+ || gio/tests/gdbus-object-manager-example/libgdbus-example-objectmanager.so+' ${BUILD_WRKSRC}/build.ninja
+
 post-patch:
 	${REINPLACE_CMD} -e 's|/usr/local|${LOCALBASE}|g ; \
 		s|/usr/share/locale/locale|${LOCALBASE}/share/locale/locale|g' \
 		${WRKSRC}/glib/gutils.c
 	${REINPLACE_CMD} -e 's|@PYTHON@|${PYTHON_CMD}|g' \
 		${WRKSRC}/gio/gdbus-2.0/codegen/gdbus-codegen.in \
 		${WRKSRC}/glib/gtester-report.in \
 		${WRKSRC}/gobject/glib-genmarshal.in \
 		${WRKSRC}/gobject/glib-mkenums.in
 	${REINPLACE_CMD} -e '/inotify_init1/d' \
 		-e '/inotify.h/d' \
 		${WRKSRC}/meson.build
 	${REINPLACE_CMD} -e 's|%%LOCALBASE%%|${LOCALBASE}|' \
 		${WRKSRC}/gio/xdgmime/xdgmime.c \
 		${WRKSRC}/glib/gutils.c \
 		${WRKSRC}/glib/tests/utils.c
 
 CODEGENDIR=	${PREFIX}/share/glib-2.0/codegen
 
 post-install:
 	${MKDIR} ${STAGEDIR}${PREFIX}/share/GConf/gsettings
 	${MKDIR} ${STAGEDIR}${PREFIX}/lib/gio/modules
 # generates .py[co] files for installed modules
 # if that's not done, ${PYTHON_SITELIBDIR}/gps will be polluted
 # with these files when module is imported from root user
 	${FIND} ${STAGEDIR}${PREFIX} -name \*.pyc -delete
 	(cd ${STAGEDIR}${PREFIX} && \
 	${PYTHON_CMD} ${PYTHON_LIBDIR}/compileall.py \
 		-d ${CODEGENDIR} -f ${CODEGENDIR:S;${PREFIX}/;;} && \
 	${PYTHON_CMD} -O ${PYTHON_LIBDIR}/compileall.py \
 		-d ${CODEGENDIR} -f ${CODEGENDIR:S;${PREFIX}/;;})
 # install bash completion regardless if bash is present
 	${MKDIR} ${STAGEDIR}${PREFIX}/share/bash-completion/completions
 .for file in gapplication gdbus gio gresource gsettings
 	${INSTALL_DATA} ${WRKSRC}/gio/completion/${file} \
 		${STAGEDIR}${PREFIX}/share/bash-completion/completions/
 .endfor
 	${RM} -r ${STAGEDIR}${PREFIX}/libexec/installed-tests
 
 .include <bsd.port.post.mk>