Windows: Add support for MINGW-UCRT based ruby

[larskanis]

RubyInstaller-3.1 is planned to be released as UCRT based build. RubyInstaller-head is already UCRT based for the x64 architecture. The x86 32-bit architecture will not change. UCRT is the modern C runtime, that MS Visual C compiler is using since years, while RubyInstaller up to 3.0 uses the ancient MSVCRT.

The main difference from a users point of view are that the PATH to the MINGW tools changes and that the MSYS2-MINGW packages have a new prefix. The PATH is
C:/msys64/ucrt64/bin/
instead of
C:/msys64/mingw64/bin/
and the package is
mingw-w64-ucrt-x86_64
instead of
mingw-w64-x86_64

The MINGW PATH is currently hardcoded here:

setup-ruby/common.js

Line 174 in 6f2028e

const msys2 = ['C:\\msys64\\mingw64\\bin', 'C:\\msys64\\usr\\bin']

It needs to be dependent on the ruby version.

Note: The ridk exec or ridk enable commands installed by RubyInstaller respect the different MINGW PATH and MINGW package prefix on UCRT already. So if ridk is used in the target project's CI, everything works already: https://github.com/oneclick/rubyinstaller2/blob/4300b3dbf4c2d9bae1522188ecccf7294b2e7617/lib/ruby_installer/build/msys2_installation.rb#L23-L35

[larskanis]

There is a corresponding issue for MINGW package installation here: ruby/setup-ruby-pkgs#15

Nokogiri is a project that fails due to wrong PATH and package prefix here: https://github.com/sparklemotion/nokogiri/runs/2837044316?check_suite_focus=true

[MSP-Greg]

@larskanis

Thanks for the info. Actions, unlike Travis or AppVeyor, isolates the ENV from step to step.

Actions has defined an API in their node.js code that allow custom actions repos (like this) to make changes to ENV['Path']. As mentioned elsewhere, I'm working on it...

[MSP-Greg]

@larskanis

I've got patches for both this repo and setup-ruby-pkgs. Two assumptions are made:

1. The Ruby so file name (RbConfig::CONFIG['RUBY_SO_NAME']) starts with x64-ucrt-ruby
2. RbConfig::CONFIG['sitearch'] == 'x64-ucrt'

The first is used to test whether it's a ucrt build without starting Ruby. That's used here.

The second is used by setup-ruby-pkgs, which does start Ruby and grabs a bunch of information from it...

If checks like that should continue to exist, I'll push two PR's...

[larskanis]

Thanks for working on this!

• The Ruby so file name (RbConfig::CONFIG['RUBY_SO_NAME']) starts with x64-ucrt-ruby
• RbConfig::CONFIG['sitearch'] == 'x64-ucrt'

The assumptions are correct and should be stable. In the unlikely event, that other ruby-core members prefer a different naming, we can change this until ruby-3.1 is released.

[larskanis]

The corresponding ticket for the changes to ruby-core is here: https://bugs.ruby-lang.org/issues/17845