* cont.c (rb_threadptr_root_fiber_setup): divide into two functions:
* rb_threadptr_root_fiber_setup_by_parent(): called by the parent thread.
* rb_threadptr_root_fiber_setup_by_child(): called by the created thread.
`rb_threadptr_root_fiber_setup()` is called by the parent thread and
set fib->fib_handle by ConvertThreadToFiber() on the parent thread on
Windows enveironment.
This means that root_fib->fib_handle of child thread is initialized
with parent thread's Fiber handle. Furthermore, second call of
`ConvertThreadToFiber()` for the same thread fails.
This patch solves this weird situateion. However, maybe we can make more
clean code.
* thread.c (thread_start_func_2): call
`rb_threadptr_root_fiber_setup_by_child()` at thread initialize routine.
* vm.c (th_init): call `rb_threadptr_root_fiber_setup_by_parent()`.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63073 b2dd03c8-39d4-4d8f-98ff-823fe69b080e