Re: bison-3.2 make fails on Solaris 11.3 x86/64

[Paul Eggert]

I installed the attached patch to Gnulib, which should fix the problem 
there. If Gnulib defines _Noreturn, doesn't that render the _Noreturn 
definition in Bison's c.m4 unnecessary?

>From 5821ccc02d138bfcb9dcc4f39bfb2abe87c9d5ed Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Fri, 2 Nov 2018 14:09:35 -0700
Subject: [PATCH] gnulib-common.m4: port _Noreturn to C++

Problem reported by Akim Demaille in:
https://lists.gnu.org/r/bug-bison/2018-10/msg00067.html
* m4/gnulib-common.m4 (gl_COMMON_BODY): If C++, use [[noreturn]].
Merge adjustments from _Noreturn.h and from glibc into the non-C++
version.
* lib/_Noreturn.h: Match gnulib-common.
---
 ChangeLog           | 10 ++++++++++
 lib/_Noreturn.h     | 12 ++++++++----
 m4/gnulib-common.m4 | 15 +++++++++------
 3 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 94f8e919f..bbf379b8c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2018-11-02  Paul Eggert  <egg...@cs.ucla.edu>
+
+	gnulib-common.m4: port _Noreturn to C++
+	Problem reported by Akim Demaille in:
+	https://lists.gnu.org/r/bug-bison/2018-10/msg00067.html
+	* m4/gnulib-common.m4 (gl_COMMON_BODY): If C++, use [[noreturn]].
+	Merge adjustments from _Noreturn.h and from glibc into the non-C++
+	version.
+	* lib/_Noreturn.h: Match gnulib-common.
+
 2018-10-30  Bruno Haible  <br...@clisp.org>
 
 	gnu-make: Fix for NetBSD 8 'make'.
diff --git a/lib/_Noreturn.h b/lib/_Noreturn.h
index c44ad89b7..94fdfaf02 100644
--- a/lib/_Noreturn.h
+++ b/lib/_Noreturn.h
@@ -1,8 +1,12 @@
-#if !defined _Noreturn && __STDC_VERSION__ < 201112
-# if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
-      || 0x5110 <= __SUNPRO_C)
+#ifndef _Noreturn
+# if 201103 <= (defined __cplusplus ? __cplusplus : 0)
+#  define _Noreturn [[noreturn]]
+# elif (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
+        || 4 < __GNUC__ + (7 <= __GNUC_MINOR__))
+   /* _Noreturn works as-is.  */
+# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 0x5110 <= __SUNPRO_C
 #  define _Noreturn __attribute__ ((__noreturn__))
-# elif 1200 <= _MSC_VER
+# elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
 #  define _Noreturn __declspec (noreturn)
 # else
 #  define _Noreturn
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index 1b8cdd567..2b253dabf 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 40
+# gnulib-common.m4 serial 41
 dnl Copyright (C) 2007-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -16,12 +16,15 @@ AC_DEFUN([gl_COMMON], [
 AC_DEFUN([gl_COMMON_BODY], [
   AH_VERBATIM([_Noreturn],
 [/* The _Noreturn keyword of C11.  */
-#if ! (defined _Noreturn \
-       || (defined __STDC_VERSION__ && 201112 <= __STDC_VERSION__))
-# if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
-      || 0x5110 <= __SUNPRO_C)
+#ifndef _Noreturn
+# if 201103 <= (defined __cplusplus ? __cplusplus : 0)
+#  define _Noreturn [[noreturn]]
+# elif (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
+        || 4 < __GNUC__ + (7 <= __GNUC_MINOR__))
+   /* _Noreturn works as-is.  */
+# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 0x5110 <= __SUNPRO_C
 #  define _Noreturn __attribute__ ((__noreturn__))
-# elif defined _MSC_VER && 1200 <= _MSC_VER
+# elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
 #  define _Noreturn __declspec (noreturn)
 # else
 #  define _Noreturn
-- 
2.19.1