[ruby-core:86778] [Ruby trunk Bug#14702] On Ruby 2.5.1, tracepoint isn't working on the file that is loaded by load_iseq

[makoto_tajitsu@hotmail.co.jp]

Issue #14702 has been updated by makoto_tajitsu@hotmail.co.jp (Makoto Tajitsu).

Description updated

How is the issue?

In addition to above, I confirm the issue in following example that does not use 3rd party gem.
```ruby
#!/usr/bin/env ruby

# Write ruby file
File.write('./loaded_file.rb', 'puts :hello')

# load file and write iseq file
iseq = RubyVM::InstructionSequence.compile_file('./loaded_file.rb')
File.write('./loaded_file.yarb', iseq.to_binary)

# define load_iseq
class RubyVM::InstructionSequence
  def self.load_iseq(fname)
    b = File.read('./loaded_file.yarb')
    RubyVM::InstructionSequence.load_from_binary(b)
  end
end

TracePoint.trace(:line) do |tp|
  puts "file: #{tp.path}, line: #{tp.lineno}" if tp.path =~ /loaded_file/
end

load './loaded_file.rb' # => on ruby 2.5.0 and 2.5.1, no tracepoint callback is.
```

----------------------------------------
Bug #14702: On Ruby 2.5.1, tracepoint isn't working on the file that is loaded by load_iseq
https://bugs.ruby-lang.org/issues/14702#change-71736

* Author: makoto_tajitsu@hotmail.co.jp (Makoto Tajitsu)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
* ruby -v: ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin16]
* Backport: 2.3: UNKNOWN, 2.4: UNKNOWN, 2.5: UNKNOWN
----------------------------------------
On Ruby 2.5.1, when loading file with RubyVM::InstructionSequence.load_from_binary, TracePoint callback event is not working on loaded file.

## Steps to reproduce

Ruby version.
```
$ ruby -v
# => ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin16]
```

The example with `yomikomu` gem which is simply used `load_iseq` and `load_from_binary` method to load file quickly is following.
```ruby
$ YOMIKOMU_AUTO_COMPILE=true bundle exec irb

> TracePoint.trace(:line) { |tp| puts tp.lineno if tp.path == '/path/to/somefile.rb' }
# => #<TracePoint:enabled>

> load '/path/to/somefile.rb'
# 3
# 4
# ...

> require 'yomikomu'

> load '/path/to/somefile.rb'
# no tracepoint callback for line event
```

## Result of reproduce process

tracepoint callback isn't called on loaded file by using load_iseq and load_from_binary.

## Expected result and the reason why you expect

tracepoint callback should be called for any loaded file to debug with debugguer(e.g. byebug).

On Ruby 2.4.3, this example is working correctly, so tracepoint callback is called and output lineno to stdout when loaded file after `require 'yomikomu'`.





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