Dear gnash maintainers, libming-dev and libming-utils is unmaintained, have unfixed security vulnerabilities and it also FTBFS without php5. As far as I understand if you drop the libming-dev and libming-util the gnash will still build, but the test suite will be severely limited.
The other option would be for Debian Flash Team to adopt the src:ming. Cheers, -- Ondřej Surý <ond...@sury.org> Knot DNS (https://www.knot-dns.cz/) – a high-performance DNS server Knot Resolver (https://www.knot-resolver.cz/) – secure, privacy-aware, fast DNS(SEC) resolver Vše pro chleba (https://vseprochleba.cz) – Mouky ze mlýna a potřeby pro pečení chleba všeho druhu