Doing require_relative too often leads to TypeError

[janlelis]

Environment

• ruby -v jruby 9.1.8.0-SNAPSHOT (2.3.1) 2017-02-06 3f97c7a Java HotSpot(TM) 64-Bit Server VM 25.111-b14 on 1.8.0_111-b14 +indy +jit [linux-x86_64]
• uname -a Linux ok 4.4.0-59-generic #80-Ubuntu SMP Fri Jan 6 17:47:47 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

Setup

Empty file: a.rb

Contents of b.rb, in the same directory:

400.times{
  require_relative 'a'
}

Expected Behavior

• Should print nothing

Actual Behavior

• Throws following error:

TypeError: no implicit conversion of nil into String
          realpath at org/jruby/RubyFile.java:862
  require_relative at uri:classloader:/jruby/kernel/kernel.rb:11
  require_relative at uri:classloader:/jruby/kernel/kernel.rb:-1
     block in b.rb at b.rb:2
             times at org/jruby/RubyFixnum.java:299
            <main> at b.rb:1

Works find for a smaller iteration count, for example, 4.

[enebo]

@janlelis two things. Can you figure out if it always happens at a particular number (e.g. 20)? Also do you have any JRUBY_OPTS set. I am not seeing this but I am using MacOS so perhaps there is a platform difference?

[janlelis]

I forgot about it, indeed, I have JRUBY_OPTS set to -Xcompile.invokedynamic=true and I can verify, without this option, the bug does not occur.

It seems to usually fail between the 50th - 100th call.

I also noticed, after rescueing the TypeError, subsequent calls to require_relative will not trigger the error again.

With this test script as b.rb:

begin
  i = 0
  while i < 100_000
    i += 1
    require_relative "a"
  end
  puts "No errors"
rescue
  puts "#{i} | #{$!}"
end

I get the following output for number in {1..10} ; do ruby b.rb ; done:

82 | no implicit conversion of nil into String
72 | no implicit conversion of nil into String
70 | no implicit conversion of nil into String
58 | no implicit conversion of nil into String
71 | no implicit conversion of nil into String
79 | no implicit conversion of nil into String
82 | no implicit conversion of nil into String
60 | no implicit conversion of nil into String
84 | no implicit conversion of nil into String
79 | no implicit conversion of nil into String

[headius]

Definitely a JIT+indy bug. I have no clue at the moment.

Can confirm.

Had an old hackish script to load all dependent source files from a sub-directory (about 120 of them) using the following code. It would error at seemingly random points in the execution, sometimes failing a little before halfway, sometimes failing right before the end. There does not seem to be a pattern to it.

It was definitely running with +indy.

Example Code

# invoked from project root, so use .. to coerce back into real path
Dir.glob('subfolder/*.rb').each {|file| require_relative("../#{file}") }

I do not recall if adding a rescue nil after the require_relative alleviated the TypeError or not (but if so, would have surely broken a dependency).