Add riscv64 to release binaries

[gounthar]

Following up on #12348 (closed 2024). There's been more demand since then, and I found a way to bring the extended build time down to about 2 minutes on riscv64.

The key issue with extended Hugo on riscv64 is that compiling vendored libsass takes many hours. But golibsass already has a dev build tag that links against the system libsass library instead. With -tags extended,dev and apt install libsass-dev, the extended build drops from ~14 hours to ~2 minutes on native riscv64 hardware.

Build evidence:

• Native build on BananaPi F3 (SpacemiT K1, rv64gc): SUCCESS
• RISE riscv64 runner: SUCCESS (https://github.com/gounthar/hugo/actions/runs/23530112758)
• hugo version: v0.160.0-DEV extended linux/riscv64

For hugoreleaser.yaml, the regular build just needs goarch: riscv64 added under container1/unix/regular. The extended build would need either:

1. Cross-compilation with riscv64-linux-gnu-gcc (like arm64 uses aarch64-linux-gnu-gcc)
2. Native build on a riscv64 runner with system libsass (-tags extended,dev)

Native riscv64 GitHub Actions runners are available through the RISE Project (https://riseproject.dev/), free for open source. To enable: install https://github.com/apps/rise-risc-v-runners on this repository.

I can put together a PR if this approach works for you.

[bep]

But golibsass already has a dev build tag that links against the system libsass library instead.

There's a reason why we build from the libsass source: To know exactly what version of libsass we're using.

But see https://gohugo.io/functions/css/sass/#transpiler

The libsass transpiler is deprecated, so if this is the prime motivation behind this proposal, we're not spending time/energy on it.

[gounthar]

Fair point on libsass being deprecated. I should have focused on the regular build instead.

The regular Hugo build is pure Go with CGO_ENABLED=0, so adding riscv64 to hugoreleaser.yaml should be straightforward. Dart Sass already ships riscv64 binaries (since v1.74.1), so users who need Sass support can install the external sass binary alongside Hugo.

Would a PR adding just goarch: riscv64 to the regular build matrix be welcome?

[ogulcanaydogan]

Hi, I'd like to add riscv64 to the release binaries. I already have two open PRs in this repo (#14686, #14695).

I'll update the goreleaser config to include linux/riscv64 builds. Should be a small change.

[gounthar]

Thanks for picking this up, @ogulcanaydogan. Happy to test any builds on native riscv64 hardware (BananaPi F3, SpacemiT K1) once you have a PR ready.