diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c
index caad2d0d0d27234c97504f567a49c4331bb8de23..73e1e8f11bbcbef9d61dc341757b9f891260da93 100644
--- a/crypto/bn/bn_gf2m.c
+++ b/crypto/bn/bn_gf2m.c
@@ -450,8 +450,7 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const int p[])
             d0 = p[k] % BN_BITS2;
             d1 = BN_BITS2 - d0;
             z[n] ^= (zz << d0);
-            tmp_ulong = zz >> d1;
-            if (d0 && tmp_ulong)
+            if (d0 && (tmp_ulong = zz >> d1))
                 z[n + 1] ^= tmp_ulong;
         }