Update nix pin with make nixpkgs

This PR introduce 3 changes:

  - Upgrade Nix stable channel from 20.03 to 20.09.

    NixOS 20.09 released at 2020-10-27, see
    <https://nixos.org/manual/nixos/stable/release-notes.html#sec-release-20.09>
    for more information.

  - Replace `git` with `gitMinimal`.

    All 6 projects (i.e. crun/conmon/skopeo/buildah/podman/cri-o) are
    having `git` as dependency for failsafe during bootstrap. BTW
    <NixOS/nixpkgs#104896> replace `asciidoc`
    with `asciidoctor` so trigger the dependency chain to `glib` and so
    failed (see below). Switching to `gitMinimal` skip this dependency
    chain to `glib`, which also speed up overall build process.

  - Adding `-pthread` for `glib`

    `conmon` couldn't skip the error by replacing `git` with
    `gitMinimal` since it do depend on `glib`. Since `glib` trigger
    error message "undefined reference to 'pthread\_create'", therefore
    adding `pthread` to `CFLAGS` could solve the problem.

Also see:

  - <containers/crun#550>
  - <containers/conmon#218>
  - <containers#1120>
  - <containers/buildah#2831>
  - <containers/podman#8526>
  - <cri-o/cri-o#4395>

Signed-off-by: Wong Hoi Sing Edison <[email protected]>

Makefile

@@ -114,7 +114,7 @@ binary: cmd/skopeo
 # Update nix/nixpkgs.json its latest stable commit
 .PHONY: nixpkgs
 nixpkgs:
- @nix run -f channel:nixos-20.03 nix-prefetch-git -c nix-prefetch-git \
+ @nix run -f channel:nixos-20.09 nix-prefetch-git -c nix-prefetch-git \
  --no-deepClone https://github.com/nixos/nixpkgs > nix/nixpkgs.json
 
 # Build statically linked binary

nix/default.nix

@@ -38,10 +38,10 @@ let
  doCheck = false;
  enableParallelBuilding = true;
  outputs = [ "out" ];
- nativeBuildInputs = [ bash git go-md2man installShellFiles makeWrapper pkg-config which ];
+ nativeBuildInputs = [ bash gitMinimal go-md2man installShellFiles makeWrapper pkg-config which ];
  buildInputs = [ glibc glibc.static gpgme libassuan libgpgerror libseccomp ];
  prePatch = ''
- export CFLAGS='-static'
+ export CFLAGS='-static -pthread'
  export LDFLAGS='-s -w -static-libgcc -static'
  export EXTRA_LDFLAGS='-s -w -linkmode external -extldflags "-static -lm"'
  export BUILDTAGS='static netgo osusergo exclude_graphdriver_btrfs exclude_graphdriver_devicemapper'

nix/nixpkgs.json

@@ -1,7 +1,10 @@
 {
  "url": "https://github.com/nixos/nixpkgs",
- "rev": "6e089d30148953df7abb3a1167169afc7848499c",
- "date": "2020-11-05T09:56:30+01:00",
- "sha256": "0ydqjkz7payl16psx445jwh6dc6lgbvj2w11xin1dqvbpcp03jcy",
- "fetchSubmodules": false
+ "rev": "6ea2fd15d881006b41ea5bbed0f76bffcd85f9f9",
+ "date": "2020-12-20T13:26:58+10:00",
+ "path": "/nix/store/kyw1ackbp9qh1jzlzwmjvi5i3541ym5z-nixpkgs",
+ "sha256": "0kgqmw4ki10b37530jh912sn49x3gay5cnmfr8yz2yp8nvkrk236",
+ "fetchSubmodules": false,
+ "deepClone": false,
+ "leaveDotGit": false
 }