Go has tools for checking things like this. It's just not in the compiler. If you don't want to enforce that all errors are checked, go doesn't force you to. If you do, it requires you to run an extra tool in your build process.
(Or in your commit hook. If you want to develop without worrying about such things, and then clean it up before checkin, that's a development approach that go is perfectly fine with.)
And the more I work with Go, the less I understand why warnings were not added to the compiler. Essentially instead of having them in the compiler itself, one needs to run a tool, which will have much smaller user base.
But anyway, in Go, it's sometimes fine to have both non-nil error and a result, e.g. the notorious EOF error.
