Protobuf: google-protobuf gem 3.1.0 is not compatible with Ruby 2.4

Created on 26 Dec 2016 · 6Comments · Source: protocolbuffers/protobuf

The reason appears to be because google-protobuf currently uses rb_cFixnum, which is not supported in Ruby 2.4 because the Fixnum/Bignum distinction has been removed. I haven't dug into where this is in the code, but this effectively prevents all gRPC-based google API clients from working on Ruby 2.4, so it needs to be addressed asap.

Repro:

% ruby --version
ruby 2.4.0p0 (2016-12-24 revision 57164) [x86_64-linux]
% gem install google-protobuf
Fetching: google-protobuf-3.1.0-x86_64-linux.gem (100%)
Successfully installed google-protobuf-3.1.0-x86_64-linux
Parsing documentation for google-protobuf-3.1.0-x86_64-linux
Installing ri documentation for google-protobuf-3.1.0-x86_64-linux
Done installing documentation for google-protobuf after 0 seconds
1 gem installed
% irb
irb(main):001:0> gem "google-protobuf"
=> true
irb(main):002:0> require "google/protobuf"
LoadError: /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/google-protobuf-3.1.0-x86_64-linux/lib/google/protobuf_c.so: undefined symbol: rb_cFixnum - /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/google-protobuf-3.1.0-x86_64-linux/lib/google/protobuf_c.so
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/google-protobuf-3.1.0-x86_64-linux/lib/google/protobuf.rb:50:in `rescue in <top (required)>'
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/google-protobuf-3.1.0-x86_64-linux/lib/google/protobuf.rb:47:in `<top (required)>'
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from (irb):2
        from /usr/local/google/home/dazuma/.rbenv/versions/2.4.0/bin/irb:11:in `<main>'
irb(main):003:0>

Source

dazuma

👍7

Most helpful comment

@palkan Sorry for the delay! We're resolving some build issues internally with the gems, but it should be any day now.

dazuma on 11 Feb 2017

👍5

All 6 comments

I believe all that needs to be done is to rebuild the gem using the Ruby 2.4 headers.

AFAICT, the current code appears to reference the Fixnum class only via pre-2.4 header macros. I also tried building the native gem against the 2.4 ruby.h, and it runs correctly on Ruby 2.4 (as well as being backward compatible with 2.3.3); whereas when I go back and rebuild the native gem against the 2.3.3 ruby.h, that fails on Ruby 2.4.

dazuma on 27 Dec 2016

Thanks for the report! In our next release we will be sure to include a binary gem for 2.4.