Subject: bazel-zig-cc v0.6.0

From: Motiejus Jakštys <[email-masked]>
Date: Thu, 7 Apr 2022 14:46:50 +0300

Hi all,

this change is a breaking change to bazel-zig-cc. Main points (from changelog):

### [laurynasl] Hide toolchain internals

This is a long-standing issue where platforms, toolchains and private stuff was
mixed together. Now platforms and toolchains are defined in their own
namespaces:

$ bazel query @zig_sdk//platform:*
@zig_sdk//platform:BUILD
@zig_sdk//platform:darwin_aarch64
@zig_sdk//platform:darwin_amd64
@zig_sdk//platform:darwin_arm64
@zig_sdk//platform:darwin_x86_64
@zig_sdk//platform:linux_aarch64
@zig_sdk//platform:linux_amd64
@zig_sdk//platform:linux_arm64
@zig_sdk//platform:linux_x86_64
@zig_sdk//platform:macos_aarch64
@zig_sdk//platform:macos_amd64
@zig_sdk//platform:macos_arm64
@zig_sdk//platform:macos_x86_64

$ bazel query @zig_sdk//toolchain:* | head -10
Loading: 0 packages loaded
@zig_sdk//toolchain:BUILD
@zig_sdk//toolchain:aarch64-linux-gnu
@zig_sdk//toolchain:aarch64-linux-gnu.2.17
@zig_sdk//toolchain:aarch64-linux-gnu.2.18
@zig_sdk//toolchain:aarch64-linux-gnu.2.19
@zig_sdk//toolchain:aarch64-linux-gnu.2.22
@zig_sdk//toolchain:aarch64-linux-gnu.2.23
@zig_sdk//toolchain:aarch64-linux-gnu.2.24
@zig_sdk//toolchain:aarch64-linux-gnu.2.25
@zig_sdk//toolchain:aarch64-linux-gnu.2.26

Thanks Laurynas!

### [Ken Micklas] Upgrade to Bazel 5.1.0

... we now require minimal bazel 5.1.0. And there are some other minor
CI improvements, like specifying golang version for reproducibility.

Laurynas is preparing a different way to specify musl and glibc
platforms by selecting the platform, not the toolchain. This should
happen soon. This was desirable from day 0, but I couldn't make it
happen reliably at the time, so resorted to `--extra_toolchains`.
Looking forward to it!

Motiejus