Indeed, there's a merge proposal for this issue. It has built successfully, but I believe GunChleoc is cleaning up some remaining issues.
It is good to have a bug report on this, so thanks for reporting. I assume it is only a matter of time before maintainers will try (or need) to rebuild Widelands with gcc7 and hopefully this branch or patch will save them duplicating too much of the work.
Indeed, there's a merge proposal for this issue. It has built successfully, but I believe GunChleoc is cleaning up some remaining issues.
It is good to have a bug report on this, so thanks for reporting. I assume it is only a matter of time before maintainers will try (or need) to rebuild Widelands with gcc7 and hopefully this branch or patch will save them duplicating too much of the work.