[jamespwilliams]

> Maybe it would be easier to have some kind of framework for compiler plugins that do extra checks. [...] But I haven't seen any language community do something like that. What am I missing?

Go has adopted a similar approach to this - they've made it fairly easy to write separate plugins that check stuff like this. The plugins aren't executed as part of the compiler though, they're standalone tools. For example, see golangci-lint, which bundles together a load of plugins of this kind.

Some of these plugins are shipped within the go command directly, as part of the "go vet" subcommand. (including a printf format check, which is similar to what's described in this post, i.e. it checks that arguments are of the correct type).