envutil.rb: under_gc_stress parameter
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43625 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
envutil.rb: under_gc_stress parameter
so that making possible to disable stressing explicitly.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43625 b2dd03c8-39d4-4d8f-98ff-823fe69b080e