--- a/libtommath/bn_mp_2expt.c	Tue May 26 23:27:26 2020 +0800
+++ b/libtommath/bn_mp_2expt.c	Tue May 26 17:36:47 2020 +0200
@@ -1,44 +1,31 @@
 #include "tommath_private.h"
 #ifdef BN_MP_2EXPT_C
-/* LibTomMath, multiple-precision integer library -- Tom St Denis
- *
- * LibTomMath is a library that provides multiple-precision
- * integer arithmetic as well as number theoretic functionality.
- *
- * The library was designed directly after the MPI library by
- * Michael Fromberger but has been written from scratch with
- * additional optimizations in place.
- *
- * SPDX-License-Identifier: Unlicense
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
 
 /* computes a = 2**b
  *
  * Simple algorithm which zeroes the int, grows it then just sets one bit
  * as required.
  */
-int mp_2expt(mp_int *a, int b)
+mp_err mp_2expt(mp_int *a, int b)
 {
-   int     res;
+   mp_err    err;
 
    /* zero a as per default */
    mp_zero(a);
 
    /* grow a to accomodate the single bit */
-   if ((res = mp_grow(a, (b / DIGIT_BIT) + 1)) != MP_OKAY) {
-      return res;
+   if ((err = mp_grow(a, (b / MP_DIGIT_BIT) + 1)) != MP_OKAY) {
+      return err;
    }
 
    /* set the used count of where the bit will go */
-   a->used = (b / DIGIT_BIT) + 1;
+   a->used = (b / MP_DIGIT_BIT) + 1;
 
    /* put the single bit in its place */
-   a->dp[b / DIGIT_BIT] = (mp_digit)1 << (mp_digit)(b % DIGIT_BIT);
+   a->dp[b / MP_DIGIT_BIT] = (mp_digit)1 << (mp_digit)(b % MP_DIGIT_BIT);
 
    return MP_OKAY;
 }
 #endif
-
-/* ref:         HEAD -> master, tag: v1.1.0 */
-/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
-/* commit time: 2019-01-28 20:32:32 +0100 */