Following a discussion that I started firstly on the Bitcoin dev's mailing list, and then on StackExchange and Reddit, regarding some weird inconsistencies I noticed when I was working on a function to derive the p2sh from a multisig script, I'm here now to report what seems to be a bug in `addmultisigaddress` method.

Reference of the discussions:
https://bitcoin.stackexchange.com/questions/87579/multisig-scripts-hashing-p2sh-difference-between-legacy-and-segwit
https://www.reddit.com/r/Bitcoin/comments/bmiuk5/multisig_scripts_hashing_p2sh_difference_between/

## Example:

```bash
bitcoin-cli addmultisigaddress 1 '["045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d","02ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831","0224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e07"]'
{
  "address": "36ULucjWUTrDvaJzCyhFoVbDoNS6Zum2Du",
  "redeemScript": "5141045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d2102ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831210224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e0753ae"
}

bitcoin-cli createmultisig 1 '["045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d","02ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831","0224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e07"]'
{
  "address": "3GiimyxF1R5VixfBFAbQZbuy9EesD2r6n1",
  "redeemScript": "5141045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d2102ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831210224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e0753ae"
}
```

## Expected behaviour:

Both the two calls should return the same legacy address, because `addmultisigaddress` uses p2sh-segwit which is the default address type for the wallet, but segwit does not support uncompressed keys, so the first call should fallback to legacy.

## Actual behaviour:

The first call is returning an invalid segwit address.

@achow101 answered to my email to the dev list and also to my question on StackExchange and he believes that this is a bug and it could be related to the fact that the uncompressed pubkey is not part of my wallet.

---

Another interesting thing is that, as user @ugamkamat pointed out on StackExchange, changing the position of the uncompressed public key from the first to the last, the first call returns a legacy address:

```bash
./bitcoin-cli addmultisigaddress 1 '["02ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831","0224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e07","045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d"]'
{
  "address": "35RZ8AHKWGGbNcRDaCUtznSVnPRWGqVPJu",
  "redeemScript": "512102ac46c6d74d15e60f4f1035ff07ef740aca1d68d55ba0b8d336a73d7a35858831210224a4dc5620714a9ecf67a09583d1e4c04f5bedb8ecea99028da05bb15a2a7e0741045897fee25bd7c5692510b2f50fcae9aa20fbc4d49d59814f4c7fdb5c4bc6eb1c0ce382458f9588e922e0d509ed8d34856787380075b00418b02e0bf7c652ef9d53ae"
}
```

I'd really like to try to contribute to the project, so I'm trying to figure out where the problem could be in the code. Any suggestion is welcome.
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp))
        return NullUniValue;
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 2) {
        throw std::runtime_error(
            RPCHelpMan{"bumpfee",
                "\nBumps the fee of an opt-in-RBF transaction T, replacing it with a new transaction B.\n"
                "An opt-in RBF transaction with the given txid must be in the wallet.\n"
                "The command will pay the additional fee by reducing change outputs or adding inputs when necessary. It may add a new change output if one does not already exist.\n"
                "If `totalFee` is given, adding inputs is not supported, so there must be a single change output that is big enough or it will fail.\n"
                "All inputs in the original transaction will be included in the replacement transaction.\n"
                "The command will fail if the wallet or mempool contains a transaction that spends one of T's outputs.\n"
                "By default, the new fee will be calculated automatically using estimatesmartfee.\n"
                "The user can specify a confirmation target for estimatesmartfee.\n"
                "Alternatively, the user can specify totalFee, or use RPC settxfee to set a higher fee rate.\n"
                "At a minimum, the new fee rate must be high enough to pay an additional new relay fee (incrementalfee\n"
                "returned by getnetworkinfo) to enter the node's mempool.\n",
                {
                    {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The txid to be bumped"},
                    {"options", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED_NAMED_ARG, "",
                        {
                            {"confTarget", RPCArg::Type::NUM,  "fallback to wallet's default", "Confirmation target (in blocks)"},
                            {"totalFee", RPCArg::Type::NUM,  "fallback to 'confTarget'", "Total fee (NOT feerate) to pay, in satoshis.\n"
            "                         In rare cases, the actual fee paid might be slightly higher than the specified\n"
            "                         totalFee if the tx change output has to be removed because it is too close to\n"
            "                         the dust threshold."},
                            {"replaceable", RPCArg::Type::BOOL,  "true", "Whether the new transaction should still be\n"