Bug #16522

Ruby 2.7 logs deprecation warning when Warning[:deprecated] is set to false.

Added by (Sneha Somwanshi) 6 months ago. Updated about 1 month ago.

Target version:



While upgrading our monolithic app to ruby 2.7, we realised that ruby 2.7 is not suppressing all deprecation warnings.

Here is the test case:

~/dev/freeagent (ruby_2_7_0 *%) $ ruby -W:no-deprecated -e 'require "json";"hello", {})'
-e:1: warning: Using the last argument as keyword parameters is deprecated

The warning is originating from and setting Warning[:deprecated] = false or RUBYOPT=-W:no-deprecated -W:no-experimental does not suppress this warning.


scan-args-deprecated-warn-16522.patch (6.79 KB) scan-args-deprecated-warn-16522.patch jeremyevans0 (Jeremy Evans), 05/29/2020 04:54 PM

Updated by (Sneha Somwanshi) 5 months ago

  • Description updated (diff)

Updated by jeremyevans0 (Jeremy Evans) 5 months ago

This no longer applies to the master branch, as the warnings have been removed.

Fixing this in 2.7 could be challenging, as the function to deduplicate warnings is static in vm_args.c. That function would have to be made non-static at least. The function also requires access to ec and iseq, and while I think ec is possible to get access to, I'm not sure about iseq.

You can work around the issue using the warning gem and using Warning.dedup.

Updated by jeremyevans0 (Jeremy Evans) about 1 month ago

I took another look at this and I think we can silence the deprecation warnings with -W:no-deprecated even if we can't deduplicate the warnings. Attached is a patch that implements this. I'm not sure if the approach in ruby.h is acceptable (rb_scan_args has both an unoptimized version in class.c and an optimized version in ruby.h).

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