--- a/libtommath/bn_mp_mul_d.c	Tue May 26 23:27:26 2020 +0800
+++ b/libtommath/bn_mp_mul_d.c	Tue May 26 17:36:47 2020 +0200
@@ -1,28 +1,20 @@
 #include "tommath_private.h"
 #ifdef BN_MP_MUL_D_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 */
 
 /* multiply by a digit */
-int mp_mul_d(const mp_int *a, mp_digit b, mp_int *c)
+mp_err mp_mul_d(const mp_int *a, mp_digit b, mp_int *c)
 {
    mp_digit u, *tmpa, *tmpc;
    mp_word  r;
-   int      ix, res, olduse;
+   mp_err   err;
+   int      ix, olduse;
 
    /* make sure c is big enough to hold a*b */
    if (c->alloc < (a->used + 1)) {
-      if ((res = mp_grow(c, a->used + 1)) != MP_OKAY) {
-         return res;
+      if ((err = mp_grow(c, a->used + 1)) != MP_OKAY) {
+         return err;
       }
    }
 
@@ -50,7 +42,7 @@
       *tmpc++ = (mp_digit)(r & (mp_word)MP_MASK);
 
       /* send carry into next iteration */
-      u       = (mp_digit)(r >> (mp_word)DIGIT_BIT);
+      u       = (mp_digit)(r >> (mp_word)MP_DIGIT_BIT);
    }
 
    /* store final carry [if any] and increment ix offset  */
@@ -58,9 +50,7 @@
    ++ix;
 
    /* now zero digits above the top */
-   while (ix++ < olduse) {
-      *tmpc++ = 0;
-   }
+   MP_ZERO_DIGITS(tmpc, olduse - ix);
 
    /* set used count */
    c->used = a->used + 1;
@@ -69,7 +59,3 @@
    return MP_OKAY;
 }
 #endif
-
-/* ref:         HEAD -> master, tag: v1.1.0 */
-/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
-/* commit time: 2019-01-28 20:32:32 +0100 */