libdbusmenu ftbfs in eoan

https://launchpadlibrarian.net/441262368/buildlog_ubuntu-eoan-amd64.libdbusmenu_16.04.1+18.10.20180917-0ubuntu1_BUILDING.txt.gz

/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I../../../libdbusmenu-glib -I.. -Wdate-time -D_FORTIFY_SOURCE=2 -pthread -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -Wall -Werror -Wno-error=deprecated-declarations -DG_LOG_DOMAIN="\"LIBDBUSMENU-GLIB\"" -g -O2 -fdebug-prefix-map=/<<BUILDDIR>>/libdbusmenu-16.04.1+18.10.20180917=. -fstack-protector-strong -Wformat -Werror=format-security -c -o libdbusmenu_glib_la-defaults.lo `test -f 'defaults.c' || echo '../../../libdbusmenu-glib/'`defaults.c
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I../../../libdbusmenu-glib -I.. -Wdate-time -D_FORTIFY_SOURCE=2 -pthread -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -Wall -Werror -Wno-error=deprecated-declarations -DG_LOG_DOMAIN=\"LIBDBUSMENU-GLIB\" -g -O2 -fdebug-prefix-map=/<<BUILDDIR>>/libdbusmenu-16.04.1+18.10.20180917=. -fstack-protector-strong -Wformat -Werror=format-security -c ../../../libdbusmenu-glib/defaults.c -fPIC -DPIC -o .libs/libdbusmenu_glib_la-defaults.o
../../../libdbusmenu-glib/defaults.c: In function ‘dbusmenu_defaults_class_init’:
../../../libdbusmenu-glib/defaults.c:67:2: warning: ‘g_type_class_add_private’ is deprecated [-Wdeprecated-declarations]
   67 | g_type_class_add_private (klass, sizeof (DbusmenuDefaultsPrivate));
      | ^~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/glib-2.0/gobject/gobject.h:24,
                 from /usr/include/glib-2.0/gobject/gbinding.h:29,
                 from /usr/include/glib-2.0/glib-object.h:23,
                 from ../../../libdbusmenu-glib/defaults.h:33,
                 from ../../../libdbusmenu-glib/defaults.c:35:
/usr/include/glib-2.0/gobject/gtype.h:1308:10: note: declared here
 1308 | void g_type_class_add_private (gpointer g_class,
      | ^~~~~~~~~~~~~~~~~~~~~~~~
../../../libdbusmenu-glib/defaults.c: In function ‘dbusmenu_defaults_init’:
../../../libdbusmenu-glib/defaults.c:77:13: error: G_ADD_PRIVATE [-Werror]
   77 | self->priv = DBUSMENU_DEFAULTS_GET_PRIVATE(self);
      | ^~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[5]: *** [Makefile:712: libdbusmenu_glib_la-defaults.lo] Error 1