Missing aarch64-linux-musl on RubyGems.org for > 22.7.0.1

[tisba]

Probably already known, just wanted to make sure it's tracked…

I was looking at why builds broke for mini_racer for aarch64-arm musl, e.g. https://github.com/rubyjs/mini_racer/actions/runs/10763648835. Looks like no aarch64-linux-musl packages got pushed to rubygems (>= 22.5.1.0): https://rubygems.org/gems/libv8-node/versions

I don't quite understand how rubygems works in regards to resolving this, but it looks like it's falling back to libv8-node-22.7.0.3-aarch64-linux and then failing (on aarch64 alpine, rubygems 3.5.18, Ruby 3.3.5):

$ gem install mini_racer --version 0.17.0.pre
Fetching mini_racer-0.17.0.pre.gem
Fetching libv8-node-22.7.0.3-aarch64-linux.gem
Successfully installed libv8-node-22.7.0.3-aarch64-linux
Building native extensions. This could take a while...
ERROR:  Error installing mini_racer:
	ERROR: Failed to build gem native extension.

    current directory: /usr/local/bundle/gems/mini_racer-0.17.0.pre/ext/mini_racer_extension
/usr/local/bin/ruby extconf.rb
checking for -lpthread... yes
checking for whether -Wl,--exclude-libs=ALL  is accepted as LDFLAGS... no
creating Makefile

current directory: /usr/local/bundle/gems/mini_racer-0.17.0.pre/ext/mini_racer_extension
make DESTDIR\= sitearchdir\=./.gem.20240909-122-f6akgp sitelibdir\=./.gem.20240909-122-f6akgp clean

current directory: /usr/local/bundle/gems/mini_racer-0.17.0.pre/ext/mini_racer_extension
make DESTDIR\= sitearchdir\=./.gem.20240909-122-f6akgp sitelibdir\=./.gem.20240909-122-f6akgp
compiling mini_racer_extension.cc
mini_racer_extension.cc: In function 'VALUE rb_heap_snapshot(VALUE, VALUE)':
mini_racer_extension.cc:1659:35: warning: 'rb_io::fd' is deprecated: rb_io_descriptor [-Wdeprecated-declarations]
 1659 |     FileOutputStream stream(fptr->fd);
      |                                   ^~
In file included from mini_racer_extension.cc:4:
/usr/local/include/ruby-3.3.0/ruby/io.h:154:9: note: declared here
  154 |     int fd;
      |         ^~
mini_racer_extension.cc:1659:35: warning: 'rb_io::fd' is deprecated: rb_io_descriptor [-Wdeprecated-declarations]
 1659 |     FileOutputStream stream(fptr->fd);
      |                                   ^~
/usr/local/include/ruby-3.3.0/ruby/io.h:154:9: note: declared here
  154 |     int fd;
      |         ^~
mini_racer_extension.cc:1659:35: warning: 'rb_io::fd' is deprecated: rb_io_descriptor [-Wdeprecated-declarations]
 1659 |     FileOutputStream stream(fptr->fd);
      |                                   ^~
/usr/local/include/ruby-3.3.0/ruby/io.h:154:9: note: declared here
  154 |     int fd;
      |         ^~
linking shared-object mini_racer_extension.so
/usr/lib/gcc/aarch64-alpine-linux-musl/13.2.1/../../../../aarch64-alpine-linux-musl/bin/ld: cannot find /usr/local/bundle/gems/libv8-node-22.7.0.3-aarch64-linux/vendor/v8/aarch64-linux-musl/libv8/obj/libv8_monolith.a: No such file or directory
collect2: error: ld returned 1 exit status
make: *** [Makefile:265: mini_racer_extension.so] Error 1

make failed, exit code 2

Gem files will remain installed in /usr/local/bundle/gems/mini_racer-0.17.0.pre for inspection.
Results logged to /usr/local/bundle/extensions/aarch64-linux-musl/3.3.0/mini_racer-0.17.0.pre/gem_make.out

[tisba]

Is there a reason why we stopped publishing aarch64-linux-musl packages to rubygems? This is currently breaking linux-arm64 musl builds for mini_racer.

ping @lloeki / @SamSaffron

[lloeki]

cross-compiling, which is a PITA with GCC (on Debian there's one in repo, but on Alpine you have to compile one).

but now there are GHA ARM runners so cross-compiling can be eschewed: https://github.com/DataDog/graft-rb/blob/55952c2e28d36f93f88fd8c0b885e09b1e3b9dd5/.github/workflows/nix.yml#L12-L25

[LenaWil]

I am sorry for asking, but is there a quick fix for mini_racer?

[tisba]

but now there are GHA ARM runners so cross-compiling can be eschewed

yeah, but availability in the public preview seems to be rather spotty. I tried to use them in some projects, also in rubyjs/mini_racer#341. Maybe it's too early to rely on them yet 🤷

[tisba]

I am sorry for asking, but is there a quick fix for mini_racer?

Other than compiling libv8 from source (not recommended)? Not really. Note that this should only be a problem on alpine/musl currently.

[tisba]

I take my comment back, I had a typo in the runs-on field. I think the ARM runners are worth a shot, @lloeki!

[tisba]

With mini_racer 0.18.0 released, I suspect this issue here will result in quite a few issues being reported. Should we put something in mini_racer's README or pin a issue or something to clarify, that aarch64-linux-musl is currently not supported by mini_racer?

/cc @SamSaffron

[SamSaffron]

yes I think so, the cross compiling is very tough , I am pro reducing our support matrix here unless someone wants to step up and own it.

[tisba]

Cross compiling should no longer be an issue, since Github's Linux ARM runners are available (I'm already using them in other projects). I'd like to help out, but this is quite a bit outside of my area of expertise :(