Bug #18669: Warning `flags ignored` is displayed for `Regexp.new(/regexp/)`

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 3.2.0dev (2022-03-30T14:08:13Z master 75efbb98af) [x86_64-darwin19]
• Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN

[koic (Koichi ITO)]

I encountered an unexpected warning in Ruby 3.2.0dev.

Reproduction code

Regexp.new(/regexp/)

Expected Behavior (Ruby 3.1.1)

No warnings.

% ruby -vwe 'Regexp.new(/regexp/)'
ruby 3.1.1p18 (2022-02-18 revision 53f5fc4236) [x86_64-darwin19]

Actual Behavior (Ruby 3.2.0dev)

warning: flags ignored is displayed.

% ruby -vwe 'Regexp.new(/regexp/)'
ruby 3.2.0dev (2022-03-30T14:08:13Z master 75efbb98af) [x86_64-darwin19]
-e:1: warning: flags ignored

I encountered it in a RuboCop build error:
https://app.circleci.com/pipelines/github/rubocop/rubocop/5974/workflows/94732274-f302-497a-a6bc-ffbf036c4e0b/jobs/213494

Perhaps https://github.com/ruby/ruby/pull/5703 change is related.

[mame (Yusuke Endoh)]

• Status changed from Open to Closed

Applied in changeset git|c499a4c28a62813752aeb894d68d92fcec850ac0.

---

re.c: stop a wrong warning of "flags ignored" on Regexp.new(//)

[Bug #18669]

[mame (Yusuke Endoh)]

Yes, it was my fault. Thank you for your report!

[koic (Koichi ITO)]

I confirmed the expected behavior in the edge Ruby. Thank you for the quick fixing!