Merge #15846: [POLICY] Make sending to future native witness outputs standard

c634b1e20 [POLICY] Make sending to future native witness outputs standard (Pieter Wuille)

Pull request description:

  As discussed in the April 18 2019 IRC meeting.

  This makes sending to future Segwit versions via native outputs (bech32) standard for relay, mempool acceptance, and mining. The reasons are:
  * This may interfere with smooth adoption of future segwit versions, if they're defined (by the sender wallet/node).
  * It violates BIP173 ("Version 0 witness addresses are always 42 or 62 characters, but implementations MUST allow the use of any version."), though admittedly this code was written before BIP173.
  * It doesn't protect much, as P2SH-embedded segwit cannot be filtered in this way.
  * As a general policy, the sender shouldn't care what the receiver likes his outputs to be.

  Note that _spending_ such outputs (including P2SH-embedded ones) remains nonstandard, as that is actually required for softfork safety.

ACKs for commit c634b1:
  MarcoFalke:
    utACK c634b1e2076d8e15a8284638475e26c691d4e100
  harding:
    Tested ACK c634b1e2076d8e15a8284638475e26c691d4e100
  meshcollider:
    utACK https://github.com/bitcoin/bitcoin/pull/15846/commits/c634b1e2076d8e15a8284638475e26c691d4e100

Tree-SHA512: e37168a1be9f445a04d4280593f0a92bdae33eee00ecd803d5eb16acb5c9cfc0f1f0a1dfbd5a0cc73da2c9928ec11cbdac7911513a78f85b789ae0d00e1b5962

0 files changed, 0 insertions, 0 deletions