Subject: Re: [Bitcoin-development] Proposal: relax the IsStandard rules for P2SH transactions

From: Peter Todd <[email-masked]>
Date: Thu, 19 Jun 2014 06:09:09 -0400

On Wed, Jun 18, 2014 at 08:52:22AM -0400, Gavin Andresen wrote:
> RE: most of Peter Todd's comments:
> 
> All of that should be separate pull requests.  Big Honking Pull Requests
> are harder to review and are more likely to be bike-shedded to death.

Well, just doing one and not the rest isn't necessarily a good idea. The
malleability protection definitely seems like a good idea, and has had
quite a bit of review.

> RE: not relaying/mining transactions with OP_NOPs so miners don't mine
> up-version transactions that are invalid under future-new-rules: I'm not
> convinced it is worth adding more code (more potential for bugs) to protect
> against something that isn't going to happen because up-version
> transactions are non-standard (due to version check) in any case.

Do we have consensus that future soft-forks to add new opcodes will
always be done in conjunction with a transaction nVersion bump? If so,
then that's ok, if not, then we should have a whitelist.

The code to restrict the opcodes to the softfork-safe subset is trivial,
a GetOp() loop and a switch statement. It can always be removed later.

Something that comes to mind is if we do always bump nVersion then
OP_NOPx always will have a parallel "do-nothing" behavior, which means
EvalScript() will always have to have code enabling that backwards
compatible behavior.

-- 
'peter'[:-1]@petertodd.org
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