[libsecp256k1] illegal argument: secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx)

[DerXanRam]

Hello brother. When i try to get my address from PK using the below code, it returns an error of [libsecp256k1] illegal argument: secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx)

the coed is

#include <ethc/account.h>
#include <ethc/hex.h>
#include <ethc/keccak256.h>
#include <iostream>

using namespace std;

void test_eth_account_address_get()
{
    struct eth_account account;
    uint8_t privkey[32] = {0xdc, 0xdf, 0x91, 0xb7, 0xb2, 0x9c, 0x4c, 0x06,
                           0x77, 0x33, 0x1b, 0x65, 0x5c, 0x0c, 0x6c, 0xf4,
                           0xe7, 0x1b, 0x6f, 0x87, 0x19, 0x27, 0x3a, 0x11,
                           0x2e, 0xe6, 0x5b, 0x63, 0x9b, 0x88, 0x8f, 0xfa};
    char out[40];
    eth_account_from_privkey(&account, privkey);
    eth_account_address_get(out, &account);
    cout << out << endl;
}
int main()
{
    test_eth_account_address_get();
}

[DerXanRam]

@mhw0 any result?

[mhw0]

Hello. Interesting, I can't reproduce this on Mac. Is this random thing or happens every time?

[mhw0]

It runs just fine on my machine. I think I'll need some linux machine to test this.

[zzzzzzch]

I've run into this issue as well. In my project, libsecp256k1 was introduced as a third party, and I'm not sure if it was the build issue that caused this problem.
So I modified the eth_ecdsa_pubkey_get function in ecdsa.c:

int eth_ecdsa_pubkey_get(uint8_t *dest, const uint8_t *privkey) {
  secp256k1_context *secp_ctx;
  // ....
  
  // secp_ctx = secp256k1_context_create(SECP256K1_CONTEXT_NONE);
  secp_ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN |
                                      SECP256K1_CONTEXT_VERIFY);
  // ...
}

using this workaround the error is gone.

Later I built libsecp256k1 and the sample code separately trying to figure out why, but the issue just didn't occur. I didn't further investigate because of the time

---

Just commenting here as a clue

[mhw0]

Hey @zzzzzzch thank you for the investigation! I'll take a look myself. Again, thank you.