GOPATH does not work like you assume: It is not a list of paths to look for your code you are trying to build but a path to your Go workspace. Please read http://golang.org/doc/code.html#Organization first. Your GOPATH must contain src
, bin
and pkg
directories, otherwise it is not a workspace.
What the error message is trying to tell you: There is no pkg
directory under your GOPATH, so the go tool cannot install what it is trying to build.