cmd/go: don't set default GOPATH to GOROOT

It will just cause confusion later as the go tool will say
"warning: GOPATH set to GOROOT (%s) has no effect".
Better to just leave GOPATH unset and get that warning instead.

Change-Id: I78ff9e87fdf4bb0460f4f6d6ee76e1becaa3e7b0
Reviewed-on: https://go-review.googlesource.com/33105
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

diff --git a/src/go/build/build.go b/src/go/build/build.go
index 0801565f02bfdfe9b8bf1e17a9b80a5886163c0a..f6aabcb3af7bf121f5da7531765d4df63a954bd3 100644 (file)
--- a/src/go/build/build.go
+++ b/src/go/build/build.go
@@ -264,7 +264,13 @@ func defaultGOPATH() string {
                env = "home"
        }
        if home := os.Getenv(env); home != "" {
-               return filepath.Join(home, "go")
+               def := filepath.Join(home, "go")
+               if def == runtime.GOROOT() {
+                       // Don't set the default GOPATH to GOROOT,
+                       // as that will trigger warnings from the go tool.
+                       return ""
+               }
+               return def
        }
        return ""
 }