Incorrect result when using BGV in the latest version (v1.1.4)

Library Questions
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1

Hello OpenFHE Team,

Again, I apologize for posting frequently, but I’ve encountered another issue that I believe is worth reporting.

Below is a minimal snippet of the code that reproduces the issue:

#include <iostream>
#include "openfhe.h"

using namespace lbcrypto;
using namespace std;

int main(void)
{
  CCParams<CryptoContextBGVRNS> parameters;
  parameters.SetRingDim(32768);
  parameters.SetMultiplicativeDepth(3);
  parameters.SetPlaintextModulus(65537);
  parameters.SetSecurityLevel(HEStd_256_classic);
  parameters.SetScalingTechnique(FIXEDMANUAL); //or FIXEDAUTO, NORESCALE

  CryptoContext<DCRTPoly> cc = GenCryptoContext(parameters);
  cc->Enable(PKE);
  cc->Enable(KEYSWITCH);
  cc->Enable(LEVELEDSHE);
  KeyPair<DCRTPoly> keyPair;
  keyPair = cc->KeyGen();
  vector<int64_t> tmp_vec_(1);
  Plaintext tmp;

  Ciphertext<DCRTPoly> x;
  vector<int64_t> tmp_vec_1 = {1};
  tmp = cc->MakePackedPlaintext(tmp_vec_1);
  x = cc->Encrypt(keyPair.publicKey, tmp);
  cc->Decrypt(keyPair.secretKey, x, &tmp);
  tmp->SetLength(1);
  tmp_vec_ = tmp->GetPackedValue();
  for (auto v : tmp_vec_)
  {
    cout << v << " ";
  }
  cout << endl;
  return 0;
}

When executed on OpenFHE v1.0.4, this code produces a correct result:

1

However, when I change it to the latest version (OpenFHE v1.1.4), it gives an incorrect result:

1222

I wanted to investigate why such a problem occurs, but I still don’t fully understand.
The program seems quite valid to me, but please let me know if there are misuses in parameter settings.

Thank you!

2

Thanks. The problem seems to be valid. I created an issue for it: Incorrect decryption results in BGV for a specific parameter set · Issue #714 · openfheorg/openfhe-development · GitHub

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