[PATCH/committed/2.24] posix_spawn: fix stack setup on ia64 [BZ #21275]

[Mike Frysinger]

The ia64-specific clone2 call expects the base of the stack mapping and
the stack size as sep arguments, not an initial stack value as on other
stack-grows-down architectures.  Reuse the stack-grows-up macro so we
pass in the right stack base.

Reported-by: Matt Turner <mattst88@gentoo.org>
(cherry picked from commit ddc3fb333469c2997798742dc0509dc1e3201d91)
---
 ChangeLog                        |  8 ++++++++
 sysdeps/unix/sysv/linux/spawni.c | 11 ++++++-----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 70b45cb71586..3a62ca633508 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2017-03-20  Mike Frysinger  <vapier@gentoo.org>
+
+	[BZ #21275]
+	* sysdeps/unix/sysv/linux/spawni.c [__ia64__] (CLONE): Rename
+	__stack to __stackbase.
+	(STACK): Invert _STACK_GROWS_DOWN and _STACK_GROWS_UP order of
+	checks so we can include defined(__ia64__) first.
+
 2017-03-15  John David Anglin  <danglin@gcc.gnu.org>
 
 	* sysdeps/hppa/dl-machine.h (DL_STACK_END): Define.
diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/linux/spawni.c
index 67e1c42426cf..c946120c3443 100644
--- a/sysdeps/unix/sysv/linux/spawni.c
+++ b/sysdeps/unix/sysv/linux/spawni.c
@@ -59,17 +59,18 @@
 #define SPAWN_ERROR	127
 
 #ifdef __ia64__
-# define CLONE(__fn, __stack, __stacksize, __flags, __args) \
-  __clone2 (__fn, __stack, __stacksize, __flags, __args, 0, 0, 0)
+# define CLONE(__fn, __stackbase, __stacksize, __flags, __args) \
+  __clone2 (__fn, __stackbase, __stacksize, __flags, __args, 0, 0, 0)
 #else
 # define CLONE(__fn, __stack, __stacksize, __flags, __args) \
   __clone (__fn, __stack, __flags, __args)
 #endif
 
-#if _STACK_GROWS_DOWN
-# define STACK(__stack, __stack_size) (__stack + __stack_size)
-#elif _STACK_GROWS_UP
+/* Since ia64 wants the stackbase w/clone2, re-use the grows-up macro.  */
+#if _STACK_GROWS_UP || defined (__ia64__)
 # define STACK(__stack, __stack_size) (__stack)
+#elif _STACK_GROWS_DOWN
+# define STACK(__stack, __stack_size) (__stack + __stack_size)
 #endif
 
 
-- 
2.12.0