[bitcoin-dev] Merkle branch verification & tail-call semantics for generalized MAST

[Luke Dashjr]

On Thursday 07 September 2017 12:38:55 AM Mark Friedenbach via bitcoin-dev 
wrote:
> Tail-call execution semantics
> BIP: https://gist.github.com/maaku/f7b2e710c53f601279549aa74eeb5368
> Code: https://github.com/maaku/bitcoin/tree/tail-call-semantics

Just noticed this doesn't count sigops toward the block sigop limit.
Is that really safe? How long would it take, to verify a malicious block with 
only inputs such that there is nearly 4 MB of sigops?

(I do already understand the difficulty in supporting the sigop limit.)

Luke