Control: tags -1 - wontfix > Version 4.12 is in unstable, was already build using gcc-7, and will > soon transition to testing thereby removing v4.10 from the archives.
No, it is not. According to the build logs at least 4.12.0-dfsg1-1 on i386 was built using gcc-6. You really should fix that. The package has a lot of dependencies, so please don't ignore that.