BN_MONT_CTX_copy
BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, const BN_MONT_CTX *from);
LCRYPTO_ALIAS(BN_MONT_CTX_copy);
if (!BN_MONT_CTX_copy(dst->mont_ctx, src->mont_ctx))
LCRYPTO_USED(BN_MONT_CTX_copy);