text/template: zero template.Template no longer safe for use #11379
Description
This program worked in Go 1.4 but crashes in Go 1.5.
package main
import "text/template"
func main() {
template.Must(new(template.Template).New("main").Parse(""))
}
It dies in Parse because the overall group was created with new(template.Template) and has a nil *common pointer. Because this worked in Go 1.4, I think we should keep it working in Go 1.5. That might mean filling in common lazily.