Wrong control flow order with Constant lookup and ||=

[MaxLap]

One of the two issues reported here jruby/jruby#4807 is affecting TruffleRuby.

The issue about ::X ||= being weird does not affect TruffleRuby.
The other ones does. Here is one of the examples showing off the problem.

The following should puts 'h1' and then fail. Instead, we get "h1" then "h3" then "h1" then fail.

(puts 'hi1'; raise 'thing'; puts 'h2';String)::Foo ||= puts 'hi3'

This is the commit that solved the issues for JRuby: jruby/jruby@8dae5af

[chrisseaton]

Wow that's crazy that we have a basic control-flow bug.

[gogainda]

Another example:

module Module1
    Var = nil
end

@c = 0
def get_module
	@c += 1
	Module1
end	

(get_module)::Var ||= 42
puts @c

on truffleruby it's 3, should be 1

[chrisseaton]

Sorry yeah we should get on and this this.

[norswap]

Fixed by b981115