JRuby & M1 Mac: invalid arch name '-arch aarch64'

[mohamedhafez]

When I try to gem install sassc under JRuby 9.3.3.0 with my M1 Macbook, I get the following error (even though it works fine under Ruby 3.0.3)

Fetching sassc-2.4.0.gem
Building native extensions. This could take a while...
ERROR:  Error installing sassc:
	ERROR: Failed to build gem native extension.

    current directory: /Users/mohamed/.rvm/gems/jruby-9.3.3.0/gems/sassc-2.4.0/ext
/Users/mohamed/.rvm/rubies/jruby-9.3.3.0/bin/jruby -I /Users/mohamed/.rvm/rubies/jruby-9.3.3.0/lib/ruby/stdlib -r ./siteconf20220222-70925-2bsyqb.rb extconf.rb
creating Makefile

current directory: /Users/mohamed/.rvm/gems/jruby-9.3.3.0/gems/sassc-2.4.0/ext
make DESTDIR\= clean

current directory: /Users/mohamed/.rvm/gems/jruby-9.3.3.0/gems/sassc-2.4.0/ext
make DESTDIR\=
compiling ./libsass/src/ast.cpp
clang: error: invalid arch name '-arch aarch64'
make: *** [ast.o] Error 1

make failed, exit code 2

Gem files will remain installed in /Users/mohamed/.rvm/gems/jruby-9.3.3.0/gems/sassc-2.4.0 for inspection.
Results logged to /Users/mohamed/.rvm/gems/jruby-9.3.3.0/extensions/universal-java-17/2.6.0/sassc-2.4.0/gem_make.out

[mohamedhafez]

@headius perhaps this would be an easy configuration fix for someone on the JRuby team? Or possibly it could be a bug in how JRuby installs C extensions on M1 Macs?

[headius]

Does the sassc gem build on CRuby on M1? This would be in the makefile for libsass so I'm not sure what we can fix on our end...

[headius]

Could be a bug in our mkmf that is providing the wrong flag for arch.

[mohamedhafez]

Yup it installs just fine for CRuby 3.0.3.

Taking a look at the Makefile generated by the CRuby installation vs the JRuby installation, there's several differences, but the ARCH_FLAG is -arch aarch64 in JRuby, and -m64 for CRuby...

[mohamedhafez]

And the only thing different between the Makefile generated by/for JRuby on an Intel Mac is that there the ARCH_FLAG variable is set to x86_64.

[headius]

Show me jruby -v just so I can be sure you are running natively on M1.

ARCH_FLAG seems like the culprit... we will need to figure out where that is being set and make sure it reflects an appropriate build flag on M1.

[mohamedhafez]

~ $ jruby -v
jruby 9.3.3.0 (2.6.8) 2022-01-19 b26de1f5c5 OpenJDK 64-Bit Server VM 17.0.2+8 on 17.0.2+8 +jit [darwin-aarch64]

[headius]

Hmm oddly enough, JRuby appears to hardcode ARCH_FLAGS to -m64 on a 64-bit platform so need to do more digging to figure out why our flags don't match CRuby.

[headius]

Ok I see now that we override the ARCH_FLAG on Mac to be -arch with either x86_64 or aarch64. I think aarch64 is appropriate for Linux, but MacOS may want it to be arm64.

[headius]

Relevant code is here:

https://github.com/jruby/jruby/blob/68764c6fee4811dfbd7996504da9400cab61d61d/core/src/main/java/org/jruby/ext/rbconfig/RbConfigLibrary.java#L440-L446

[headius]

This seems to be a case where MacOS prefers arm64 instead of aarch64 for the OS, so I have pushed jruby/jruby#7132 to fix this in JRuby 9.3.4.0.

This might be relevant on Linux/aarch64 as well but I do not have such a machine to test against right now. I can confirm the fix above does allow sassc to build on JRuby on MacOS/M1.

[headius]

I've merged the fixes into JRuby's 9.3.x branch and they will go out sometime soon in 9.3.4.

[mungler]

Are there any workarounds for this until 9.3.4.0 comes out? This prevents me from working on my M1 machine.