[ruby-cvs:67007] ko1:r59829 (trunk): clear `stack_end`.

[ko1 at ruby-lang.org]

ko1	2017-09-11 02:30:16 +0900 (Mon, 11 Sep 2017)

  New Revision: 59829

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=59829

  Log:
    clear `stack_end`.
    
    * cont.c (cont_save_thread): clear only `stack_end`. Clearing tells
      GC mark function to ignore this macine stack (not allocated yet).
      `stack_start` will be used by machine stack store/restore phase
      (on FIBER_USE_NATIVE == 0), so that only `stack_end` is cleared.

  Modified files:
    trunk/cont.c