From d67e300f28b04c1de1a0ef5fa95f8e882314316d Mon Sep 17 00:00:00 2001
From: Alex Brainman <alex.brainman@gmail.com>
Date: Thu, 23 May 2013 14:13:02 +1000
Subject: [PATCH] cmd/go: check GOROOT directory is present before acting

Fixes #5042.

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/7786047
---
 src/cmd/go/main.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/cmd/go/main.go b/src/cmd/go/main.go
index 3180dbeed24..a09a75cd3ec 100644
--- a/src/cmd/go/main.go
+++ b/src/cmd/go/main.go
@@ -144,6 +144,11 @@ func main() {
 		}
 	}
 
+	if fi, err := os.Stat(goroot); err != nil || !fi.IsDir() {
+		fmt.Fprintf(os.Stderr, "go: cannot find GOROOT directory: %v\n", goroot)
+		os.Exit(2)
+	}
+
 	for _, cmd := range commands {
 		if cmd.Name() == args[0] && cmd.Run != nil {
 			cmd.Flag.Usage = func() { cmd.Usage() }