use secp256k1 library with system

[jjz]

Used in the system of library . not local library
So secp256k1-go no longer need to use submodulehttps://github.com/bitcoin-core/secp256k1 , We can use the secp256k1-go as a cgo library . Users need to compile their own installation secp256k1(c)

[afk11]

Great suggestion, however upstream does not use versioning (so git submodules are helpful, if only for this reason), and have introduced API breaks in the past (removal of Schnorr signatures, various changes in convention, etc).

I would rather keep the submodule (for now) because each commit in this repo links to the version it should be built against, so in 6 months time even if upstream changes master building should still work.

Once it's released there should be official packages in debian and ubuntu, so we can just aim to support those instead of every commit.

[jjz]

submodule is used to compile and install , without having to depend in cgo 。
it's released there should be official packages in debian and ubuntu
is anybody doing this ?

[afk11]

There is an unofficial package in debian stretch (https://packages.debian.org/stretch/libsecp256k1-0), but the developers haven't formally released the code, and haven't signed his release. It's definitely 'use at your own risk' until there are gitian builds by the authors & others.

As for when the library maintainers will make a formal release, I am not sure. There has been an open issue about it since 2015, but it hasn't stopped people from using it anyway