--- a/libtommath/bn_mp_mod.c	Tue May 26 23:27:26 2020 +0800
+++ b/libtommath/bn_mp_mod.c	Tue May 26 17:36:47 2020 +0200
@@ -1,44 +1,31 @@
 #include "tommath_private.h"
 #ifdef BN_MP_MOD_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 */
 
 /* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
-int mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
+mp_err mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
 {
    mp_int  t;
-   int     res;
+   mp_err  err;
 
-   if ((res = mp_init_size(&t, b->used)) != MP_OKAY) {
-      return res;
+   if ((err = mp_init_size(&t, b->used)) != MP_OKAY) {
+      return err;
    }
 
-   if ((res = mp_div(a, b, NULL, &t)) != MP_OKAY) {
-      mp_clear(&t);
-      return res;
+   if ((err = mp_div(a, b, NULL, &t)) != MP_OKAY) {
+      goto LBL_ERR;
    }
 
-   if ((mp_iszero(&t) != MP_NO) || (t.sign == b->sign)) {
-      res = MP_OKAY;
+   if (MP_IS_ZERO(&t) || (t.sign == b->sign)) {
+      err = MP_OKAY;
       mp_exch(&t, c);
    } else {
-      res = mp_add(b, &t, c);
+      err = mp_add(b, &t, c);
    }
 
+LBL_ERR:
    mp_clear(&t);
-   return res;
+   return err;
 }
 #endif
-
-/* ref:         HEAD -> master, tag: v1.1.0 */
-/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
-/* commit time: 2019-01-28 20:32:32 +0100 */