lukeh@Lukes-MacBook-Pro:~/dd/temp/go$ go get -u sourcegraph.com/sqs/goreturns
package golang.org/x/tools/go/gcimporter: cannot find package "golang.org/x/tools/go/gcimporter" in any of:
/usr/local/go/src/golang.org/x/tools/go/gcimporter (from $GOROOT)
/Users/lukeh/dd/temp/go/src/golang.org/x/tools/go/gcimporter (from $GOPATH)
package golang.org/x/tools/go/types: no buildable Go source files in /Users/lukeh/dd/temp/go/src/golang.org/x/tools/go/types
This appears to be happening after the change announced here: https://groups.google.com/forum/#!topic/golang-announce/qu_rAphYdxY, and implemented here: https://github.com/golang/tools/commit/adaaa074861b0d254acf51dec74daf7c2ba20e90.