Merge branch 'nd/diff-parseopt'

A brown-paper-bag bugfix to a change already in 'master'.

* nd/diff-parseopt:
  parse-options: check empty value in OPT_INTEGER and OPT_ABBREV
  diff-parseopt: restore -U (no argument) behavior
  diff-parseopt: correct variable types that are used by parseopt

parse-options.c

@@ -195,6 +195,9 @@ static enum parse_opt_result get_value(struct parse_opt_ctx_t *p,
 		}
 		if (get_arg(p, opt, flags, &arg))
 			return -1;
+		if (!*arg)
+			return error(_("%s expects a numerical value"),
+				     optname(opt, flags));
 		*(int *)opt->value = strtol(arg, (char **)&s, 10);
 		if (*s)
 			return error(_("%s expects a numerical value"),