From c193a87ae1a3499ee6fb1494f548d56505721a1e Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <brad@danga.com>
Date: Tue, 17 Apr 2018 13:31:33 -0700
Subject: [PATCH] make.go: don't fail to build gopherjs if it doesn't already
 exist

Fixes #1096

Change-Id: I71c3a48248503b94ef0b4415083ccf95b5bb6265
---
 make.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/make.go b/make.go
index 0032385bb..61b568ed1 100644
--- a/make.go
+++ b/make.go
@@ -278,10 +278,11 @@ func buildGopherjs() error {
 		return err
 	}
 	modtime := time.Now()
+	var hashBefore string
 	if err == nil {
 		modtime = fi.ModTime()
+		hashBefore = hashsum(outBin)
 	}
-	hashBefore := hashsum(outBin)
 
 	src := filepath.Join(pkRoot, filepath.FromSlash("vendor/github.com/gopherjs/gopherjs"))
 	goBin := "go"