diff --git a/lib/hcrypto/libtommath/bn_mp_find_prime.c b/lib/hcrypto/libtommath/bn_mp_find_prime.c
index ef7b6532c..d007acbef 100644
--- a/lib/hcrypto/libtommath/bn_mp_find_prime.c
+++ b/lib/hcrypto/libtommath/bn_mp_find_prime.c
@@ -5,7 +5,7 @@
  * Love Hornquist Astrand <lha@h5l.org>
  */
 #include <tommath.h>
-
+#ifdef BN_MP_FIND_PRIME_C
 int mp_find_prime(mp_int *a)
 {
   int res;
@@ -24,3 +24,4 @@ int mp_find_prime(mp_int *a)
 
   return res;
 }
+#endif
diff --git a/lib/hcrypto/libtommath/bn_mp_isprime.c b/lib/hcrypto/libtommath/bn_mp_isprime.c
index d3678d5dc..f12358778 100644
--- a/lib/hcrypto/libtommath/bn_mp_isprime.c
+++ b/lib/hcrypto/libtommath/bn_mp_isprime.c
@@ -8,7 +8,7 @@
  * Tom St Denis, tomstdenis@gmail.com
  */
 #include <tommath.h>
-
+#ifdef BN_MP_ISPRIME_C
 /* a few primes */
 static const mp_digit primes[256] = {
   0x0002, 0x0003, 0x0005, 0x0007, 0x000B, 0x000D, 0x0011, 0x0013,
@@ -73,3 +73,4 @@ int mp_isprime(mp_int *a)
    }
    return MP_YES;
 }
+#endif
diff --git a/lib/hcrypto/libtommath/tommath_class.h b/lib/hcrypto/libtommath/tommath_class.h
index fa95a0277..8fd0f52f4 100644
--- a/lib/hcrypto/libtommath/tommath_class.h
+++ b/lib/hcrypto/libtommath/tommath_class.h
@@ -42,6 +42,7 @@
 #define BN_MP_EXPTMOD_C
 #define BN_MP_EXPTMOD_FAST_C
 #define BN_MP_EXTEUCLID_C
+#define BN_MP_FIND_PRIME_C
 #define BN_MP_FREAD_C
 #define BN_MP_FWRITE_C
 #define BN_MP_GCD_C
@@ -55,6 +56,7 @@
 #define BN_MP_INIT_SIZE_C
 #define BN_MP_INVMOD_C
 #define BN_MP_INVMOD_SLOW_C
+#define BN_MP_ISPRIME_C
 #define BN_MP_IS_SQUARE_C
 #define BN_MP_JACOBI_C
 #define BN_MP_KARATSUBA_MUL_C