release VM stack properly.

* cont.c: r55766 change the handling method of Fiber's VM stack.
  Resumed Fiber points NULL as VM stack and running Thread has
  responsibility to manage it (marking and releasing).

  However, thread_start_func_2()@thread.c and thread_free()@vm.c
  doesn't free the VM stack if corresponding root Fiber is exist.
  This causes memory leak. [Bug #13772]

* cont.c (root_fiber_alloc): fib->cont.saved_thread.ec.stack should be NULL
  because running thread has responsibility to manage this stack.

* vm.c (rb_thread_recycle_stack_release): assert given stack is not NULL
  (callers should care it).


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59462 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/cont.c b/cont.c
index 095cc86767..a43950c6cb 100644
--- a/cont.c
+++ b/cont.c
@@ -1288,6 +1288,7 @@ root_fiber_alloc(rb_thread_t *th)
     rb_fiber_t *fib;
     /* no need to allocate vm stack */
     fib = fiber_t_alloc(fiber_alloc(rb_cFiber));
+    fib->cont.saved_thread.ec.stack = NULL;
     fib->cont.type = ROOT_FIBER_CONTEXT;
 #if FIBER_USE_NATIVE
 #ifdef _WIN32