On 12/11/19 6:43 PM, Bruno Haible wrote:
../../gltests/test-stdalign.c:94: assertion '(uintptr_t) &(static_char_Alignas)
% TEST_ALIGNMENT == 0' failed
IOT/Abort trap (core dumped)
With xlclang 16.01, __attribute__ ((__aligned__ (N))) does not work on
external variables; the attribute is ignored. Curious, since the
attribute does work with plain xlc. Anyway, I installed the attached
patch to work around the problem.
The following program illustrates the bug, which occurs with both
_Alignas and __attribute__ ((__aligned__)). Perhaps if someone reading
this knows how to file a bug report with IBM (I don't and couldn't
easily find out), they could file a bug report against xlclang.
char _Alignas (8) c1, c2;
char __attribute__ ((__aligned__ (8))) c3, c4;
int
main (void)
{
if ((unsigned long) &c1 % 8 != 0) return 1;
if ((unsigned long) &c2 % 8 != 0) return 2;
if ((unsigned long) &c3 % 8 != 0) return 3;
if ((unsigned long) &c4 % 8 != 0) return 4;
return 0;
}
>From 7de83dd63256de8945aa06cf6ec85d64e1eea522 Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Thu, 12 Dec 2019 10:16:13 -0800
Subject: [PATCH] stdalign: port to xlclang 16.01
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Problem reportd by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2019-12/msg00064.html
* lib/stdalign.in.h (_Alignas): Do not use __attribute__
((__aligned__ (...))) with xlclang, as a top-level
‘char __attribute__ ((__aligned__ (8))) c;’ does not work with
xlclang version 16.01.0000.0001; the alignment directive is ignored.
---
ChangeLog | 10 ++++++++++
lib/stdalign.in.h | 2 +-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/ChangeLog b/ChangeLog
index 6f4f764de..a22fa7229 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2019-12-12 Paul Eggert <egg...@cs.ucla.edu>
+
+ stdalign: port to xlclang 16.01
+ Problem reportd by Bruno Haible in:
+ https://lists.gnu.org/r/bug-gnulib/2019-12/msg00064.html
+ * lib/stdalign.in.h (_Alignas): Do not use __attribute__
+ ((__aligned__ (...))) with xlclang, as a top-level
+ ‘char __attribute__ ((__aligned__ (8))) c;’ does not work with
+ xlclang version 16.01.0000.0001; the alignment directive is ignored.
+
2019-12-12 Bruno Haible <br...@clisp.org>
duplocale: Fix test failure on AIX 7.2 with xlclang.
diff --git a/lib/stdalign.in.h b/lib/stdalign.in.h
index 5c2c72e2b..257c33764 100644
--- a/lib/stdalign.in.h
+++ b/lib/stdalign.in.h
@@ -102,7 +102,7 @@
# define _Alignas(a) alignas (a)
# elif ((defined __APPLE__ && defined __MACH__ \
? 4 < __GNUC__ + (1 <= __GNUC_MINOR__) \
- : __GNUC__) \
+ : __GNUC__ && !defined __ibmxl__) \
|| (__ia64 && (61200 <= __HP_cc || 61200 <= __HP_aCC)) \
|| __ICC || 0x590 <= __SUNPRO_C || 0x0600 <= __xlC__)
# define _Alignas(a) __attribute__ ((__aligned__ (a)))
--
2.23.0
