fail softly, as documented

gitver.go

@@ -6,7 +6,6 @@ import (
 	"bytes"
 	"fmt"
 	"go/format"
-	"log"
 	"os"
 	"text/template"
 	"time"
@@ -45,9 +44,14 @@ func main() {
 
 	v, err := gitver.ExecAndParse()
 	if nil != err {
-		log.Fatalf("Failed to get git version: %s\n", err)
+		fmt.Fprintf(os.Stderr, "Failed to get git version: %s\n", err)
+		if exitCode > 0 {
 			os.Exit(exitCode)
 		}
+		v = &gitver.Versions{
+			Timestamp: time.Now(),
+		}
+	}
 
 	// Create or overwrite the go file from template
 	var buf bytes.Buffer
@@ -89,7 +93,9 @@ var versionTpl = template.Must(template.New("").Parse(`// Code generated by go g
 package {{ .Package }}
 
 func init() {
+	{{ if .GitRev -}}
 	GitRev = "{{ .GitRev }}"
+	{{ end -}}
 	{{ if .Version -}}
 	GitVersion = "{{ .Version }}"
 	{{ end -}}