gdpc: help needed to fix autopkgtest failure

I ported gdpc to GTK 3 (#967379) but the autopkgtest fails on Salsa with:

xvfb-run --auto-servernum \
	/usr/bin/gdpc m 1 d 10 erase xyz 2 3 4 5 md.test 2>&1 \
	| tee --append test.log &
sleep 10
(gdpc:3571): dbind-WARNING **: 19:54:11.885: AT-SPI: Error retrieving accessibility bus address: org.freedesktop.DBus.Error.ServiceUnknown: The name org.a11y.Bus was not provided by any .service files
*** buffer overflow detected ***: terminated
Aborted

I cannot reproduce on amd64 and i386 (real steel) so I would
appreciate if someone could try and provide a gdb backtrace.

This message comes from glibc and is an indication of a real bug.  I
believe the architecture restriction which happened in the past due to
such failures (#981876) is unjustified and all those failures were due
to this bug (or bugs).