I don't know why I've been downvoted. Maybe my question wasn't clear. Since there is no need anymore for a C compiler in the Go toolset, how will the magic import "C" package work ?

If you want to use cgo you still need a C compiler for that. But it's the system C compiler (clang or gcc), not the one we deleted.

OK, thanks for the information.

Cgo is written in Go as well: https://github.com/golang/go/tree/master/src/cmd/cgo