Dear Gnulib maintainers,
AC_CHECK_HEADER_STDBOOL needs a fix, now that GCC 6 defaults to a C++11
dialect, which breaks the assumption that stdbool.h is allowed to
unconditionally define "false" as a macro.
Greetings from Gentoo
David
From 869dbef1edc58cc4918dfeba9c680452bff4279e Mon Sep 17 00:00:00 2001
From: David Seifert <s...@gentoo.org>
Date: Mon, 30 May 2016 22:54:32 +0200
Subject: [PATCH] Amend AC_CHECK_HEADER_STDBOOL for C++11 and modern dialects
---
m4/stdbool.m4 | 39 +++++++++++++++++++++------------------
1 file changed, 21 insertions(+), 18 deletions(-)
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4
index 625520f..0863847 100644
--- a/m4/stdbool.m4
+++ b/m4/stdbool.m4
@@ -5,7 +5,7 @@ dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
-#serial 5
+#serial 6
# Prepare for substituting <stdbool.h> if it is not supported.
@@ -43,23 +43,26 @@ AC_DEFUN([AC_CHECK_HEADER_STDBOOL],
[AC_LANG_PROGRAM(
[[
#include <stdbool.h>
- #ifndef bool
- "error: bool is not defined"
- #endif
- #ifndef false
- "error: false is not defined"
- #endif
- #if false
- "error: false is not 0"
- #endif
- #ifndef true
- "error: true is not defined"
- #endif
- #if true != 1
- "error: true is not 1"
- #endif
- #ifndef __bool_true_false_are_defined
- "error: __bool_true_false_are_defined is not defined"
+
+ #if __cplusplus < 201103L
+ #ifndef bool
+ "error: bool is not defined"
+ #endif
+ #ifndef false
+ "error: false is not defined"
+ #endif
+ #if false
+ "error: false is not 0"
+ #endif
+ #ifndef true
+ "error: true is not defined"
+ #endif
+ #if true != 1
+ "error: true is not 1"
+ #endif
+ #ifndef __bool_true_false_are_defined
+ "error: __bool_true_false_are_defined is not defined"
+ #endif
#endif
struct s { _Bool s: 1; _Bool t; } s;
--
2.8.1
