terraform 0.7.0 error on upgrade via homebrew

terraform-go.md

[sebamontini@sebaMBP /Users/sebamontini $ brew info terraform
terraform: stable 0.7.0, HEAD
Tool to build, change, and version infrastructure
https://www.terraform.io/
/usr/local/Cellar/terraform/0.6.16 (46 files, 819.8M) *
  Poured from bottle on 2016-07-04 at 16:21:43
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/terraform.rb
==> Dependencies
Build: go ✔
==> Caveats
zsh completion has been installed to:
  /usr/local/share/zsh/site-functions
[sebamontini@sebaMBP /Users/sebamontini $ brew upgrade terraform
Warning: You are using OS X 10.12.
We do not provide support for this pre-release version.
You may encounter build failures or other breakages.
Please create pull-requests instead of filing issues.
==> Upgrading 1 outdated package, with result:
terraform 0.7.0
go: This formula either does not compile or function as expected on OS X
versions newer than El Capitan due to an upstream incompatibility.
Error: An unsatisfied requirement failed this build.