# HG changeset patch
# User Jerry James <james@xemacs.org>
# Date 1429564151 21600
# Node ID 23178aa71f8b985a32f9b80e5c6da660700a0315
# Parent  d3d073aceaea16ee1625363380337b3dad916861
Define ALIGNOF using C11 and C++11 operators.
See <CAHCOHQmG51R61KwGUNY7T5t9tXxzbyg=aGijUKYstbE+wL2-6Q@mail.gmail.com> in
xemacs-patches for more information.

diff -r d3d073aceaea -r 23178aa71f8b src/ChangeLog
--- a/src/ChangeLog	Sat Apr 18 23:10:40 2015 +0100
+++ b/src/ChangeLog	Mon Apr 20 15:09:11 2015 -0600
@@ -1,3 +1,9 @@
+2015-04-20  Jerry James  <james@xemacs.org>
+
+	* lisp.h (max_align_t): Do not define if C11 or C++11, or a later
+	version of either, is in use.
+	(ALIGNOF): Define with native operators in C11 and C++11 and later.
+
 2015-04-18  Aidan Kehoe  <kehoea@parhasard.net>
 
 	* sequence.c (Fclear_string): New, API from GNU.  Zero a string's
diff -r d3d073aceaea -r 23178aa71f8b src/lisp.h
--- a/src/lisp.h	Sat Apr 18 23:10:40 2015 +0100
+++ b/src/lisp.h	Mon Apr 20 15:09:11 2015 -0600
@@ -1154,6 +1154,8 @@
 
 /* ------------------------ alignment definitions ------------------- */
 
+#if (!defined (__STDC_VERSION__) || __STDC_VERSION__ < 201112L) && \
+    (!defined (__cplusplus) || __cplusplus < 201103L)
 /* No type has a greater alignment requirement than max_align_t.
    (except perhaps for types we don't use, like long double) */
 typedef union
@@ -1163,6 +1165,7 @@
   struct { void (*f)(void); } f;
   struct { double d; } d;
 } max_align_t;
+#endif
 
 /* ALIGNOF returns the required alignment of a type -- i.e. a value such
    that data of this type must begin at a memory address which is a
@@ -1170,7 +1173,11 @@
    as the type itself. */
 
 #ifndef ALIGNOF
-# if defined (__GNUC__) && (__GNUC__ >= 2)
+# if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+#  define ALIGNOF(type) _Alignof(type)
+# elif defined (__cplusplus) && __cplusplus >= 201103L
+#  define ALIGNOF(type) alignof(type)
+# elif defined (__GNUC__) && (__GNUC__ >= 2)
 /* gcc has an extension that gives us exactly what we want. */
 #  define ALIGNOF(type) __alignof__ (type)
 # elif ! defined (__cplusplus)