Smart config file

tools/build/go.go

@@ -9,7 +9,7 @@ import (
 
 func buildV2Ray(targetFile string, version string, goOS GoOS, goArch GoArch) error {
 	ldFlags := "-s"
-	if version != "" {
+	if version != "custom" {
 		year, month, day := time.Now().UTC().Date()
 		today := fmt.Sprintf("%04d%02d%02d", year, int(month), day)
 		ldFlags = ldFlags + " -X github.com/v2ray/v2ray-core.version=" + version + " -X github.com/v2ray/v2ray-core.build=" + today
@@ -17,6 +17,9 @@ func buildV2Ray(targetFile string, version string, goOS GoOS, goArch GoArch) err
 	cmd := exec.Command("go", "build", "-o", targetFile, "-compiler", "gc", "-ldflags", ldFlags, "github.com/v2ray/v2ray-core/release/server")
 	cmd.Env = append(cmd.Env, "GOOS="+string(goOS), "GOARCH="+string(goArch))
 	cmd.Env = append(cmd.Env, os.Environ()...)
-	_, err := cmd.Output()
+	output, err := cmd.CombinedOutput()
+	if len(output) > 0 {
+		fmt.Println(string(output))
+	}
 	return err
 }