* thread_pthread.c (getstack): __pi_stacksize returned by

  pthread_getthrds_np() is wrong on AIX. Use
  __pi_stackend - __pi_stackaddr instead.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54000 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 10 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 37e9b4f457..6dcc17d637 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sat Mar  5 03:07:40 2016  Rei Odaira  <Rei.Odaira@gmail.com>
+
+	* thread_pthread.c (getstack): __pi_stacksize returned by
+	  pthread_getthrds_np() is wrong on AIX. Use
+	  __pi_stackend - __pi_stackaddr instead.
+
 Fri Mar  4 19:19:42 2016  Koichi Sasada  <ko1@atdot.net>
 
 	* gc.c: use 2 bits with unsigned int for rb_objspace::flags::mode
diff --git a/thread_pthread.c b/thread_pthread.c
index 738ad57ce0..ef43b369e7 100644
--- a/thread_pthread.c
+++ b/thread_pthread.c
@@ -619,7 +619,10 @@ get_stack(void **addr, size_t *size)
 				   &thinfo, sizeof(thinfo),
 				   &reg, &regsiz));
     *addr = thinfo.__pi_stackaddr;
-    *size = thinfo.__pi_stacksize;
+    /* Must not use thinfo.__pi_stacksize for size.
+       It is around 3KB smaller than the correct size
+       calculated by thinfo.__pi_stackend - thinfo.__pi_stackaddr. */
+    *size = thinfo.__pi_stackend - thinfo.__pi_stackaddr;
     STACK_DIR_UPPER((void)0, (void)(*addr = (char *)*addr + *size));
 #elif defined __HAIKU__
     thread_info info;