Package: src:openmsx Version: 20.0+dfsg-1.1 Severity: serious Tags: sid trixie ftbfs patch
discussion in https://gcc.gnu.org/PR120415, it turns out that the openmsx code is invalid, and also is changed upstream.
patch at http://launchpadlibrarian.net/794920124/openmsx_20.0+dfsg-1.1_20.0+dfsg-1.1ubuntu1.diff.gz
