The bitcoin-cli help states that for each "prevtxs", "amount" is a required field. When I use signrawtransaction to do an offline signing of a segwit spend, if I omit this field, instead of an error message, I get an invalid signature.

Expected behavior

When I omit the required "amount" field, I expect bitcoin-cli to report an error message. (Perhaps, for backward compatibility, it should only be an error if the amount is actually used in the signature calculation.)

Actual behavior

I get a complete, apparently good transaction, but when I attempt to broadcast it using sendrawtransaction, I get the following error:

64: non-mandatory-script-verify-flag (Signature must be zero for failed CHECK(MULTI)SIG operation) (code -26)

When I include amount, I get a good transaction that differs only in the witness signatures for this input.

To reproduce

I'm running on my own Linux build of Bitcoin Core from tag v0.16.0rc3.

This script shows the issue [output]. The first call to signrawtransaction is missing the amount.

When you provide the amount during an offline signing process with signrawtransaction , I would expect that the outpoint – where you have provided the invalid amount – is not available (because the UTXO set is not present nor do you have wallet unspents). In a such case (complete offline signing), I'd say it's impossible to detect an invalid amount.

It's impossible to detect an invalid amount, but it's easy to detect when no amount at all is given, which is what I'm asking for.

From bitcoin-cli help signrawtransaction:

2. "prevtxs"       (string, optional) An json array of previous dependent transaction outputs
     [               (json array of json objects, or 'null' if none provided)
       {
         "txid":"id",             (string, required) The transaction id
         "vout":n,                  (numeric, required) The output number
         "scriptPubKey": "hex",   (string, required) script key
         "redeemScript": "hex",   (string, required for P2SH or P2WSH) redeem script
         "amount": value            (numeric, required) The amount spent
       }
       ,...
    ]

When I fail to provide the other required fields (scriptPubKey, txid, or vout) I get the following:

error code: -3
error message:
Missing txid

Shouldn't amount behave the same way?

any update on this, I am getting the same