Seems weird to fork a compiler like gcc or clang via transpilation, because you split the community. It may be faster to iterate on Go, but will all of the compiler contributors on GCC or Clang/LLVM want to switch to editing the go version?

It seems you'd lose out on picking up improvements from the main compiler branch and have to keep transpiling and gardening in patches. Plus upstreaming improvements would also be irritating.

I'd think a Go frontend to LLVM would be optimal in terms of productivity.