const go/build.safeString

2 uses

	go/build (current package)
		build.go#L1773: const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$@%! ~^"
		build.go#L1780: 		if c := s[i]; c < utf8.RuneSelf && strings.IndexByte(safeString, c) < 0 {