>From f2f0962f49f89ccb2463b3336cae2ad271954047 Mon Sep 17 00:00:00 2001
From: Paul Eggert
Date: Wed, 17 Aug 2016 15:33:06 -0700
Subject: [PATCH] stdbool: don't require _Bool for C++
Problem reported by David Seifert in:
http://lists.gnu.org/archive/html/bug-gnulib/2016-06/msg00005.html
* NEWS, doc/posix-headers/stdbool.texi (stdbool.h): Document this.
* m4/stdbool.m4 (AC_CHECK_HEADER_STDBOOL): Make the check
more-forgiving for C++, in that it requires only 'bool'. Be a bit
stricter about checking that bool and _Bool are compatible in C.
---
ChangeLog | 10 ++++++++++
NEWS | 4 ++++
doc/posix-headers/stdbool.texi | 3 ++-
m4/stdbool.m4 | 28 ++++++++++++++++------------
4 files changed, 32 insertions(+), 13 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index e899eb4..ddacf1e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2016-08-17 Paul Eggert
+
+ stdbool: don't require _Bool for C++
+ Problem reported by David Seifert in:
+ http://lists.gnu.org/archive/html/bug-gnulib/2016-06/msg00005.html
+ * NEWS, doc/posix-headers/stdbool.texi (stdbool.h): Document this.
+ * m4/stdbool.m4 (AC_CHECK_HEADER_STDBOOL): Make the check
+ more-forgiving for C++, in that it requires only 'bool'. Be a bit
+ stricter about checking that bool and _Bool are compatible in C.
+
2016-08-16 Paul Eggert
getdelim: remove dependency on realloc-posix
diff --git a/NEWS b/NEWS
index 00709e8..e33d350 100644
--- a/NEWS
+++ b/NEWS
@@ -42,6 +42,10 @@ User visible incompatible changes
Date Modules Changes
+2016-08-17 stdbool This no longer supports _Bool for C++.
+ Programs intended to be portable to C++
+ compilers should use plain 'bool' instead.
+
2016-04-12 intprops The following macros were removed:
TYPE_TWOS_COMPLEMENT TYPE_ONES_COMPLEMENT
TYPE_SIGNED_MAGNITUDE
diff --git a/doc/posix-headers/stdbool.texi b/doc/posix-headers/stdbool.texi
index 50afbd4..bac30aa 100644
--- a/doc/posix-headers/stdbool.texi
+++ b/doc/posix-headers/stdbool.texi
@@ -20,7 +20,8 @@ OpenBSD 4.7 with gcc 2.95.
Portability problems not fixed by Gnulib:
@itemize
@item
address@hidden} must be #included before @samp{_Bool} can be used.
address@hidden cannot be used before @code{} is included, or if
+the program is intended to be compiled by a C++ compiler.
@item
You cannot assume that @code{_Bool} is a typedef; it might be a macro.
@item
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4
index a556153..2a9b1db 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 6
+#serial 7
# Prepare for substituting if it is not supported.
@@ -44,7 +44,10 @@ AC_DEFUN([AC_CHECK_HEADER_STDBOOL],
[[
#include
- #if __cplusplus < 201103
+ #ifdef __cplusplus
+ typedef bool Bool;
+ #else
+ typedef _Bool Bool;
#ifndef bool
"error: bool is not defined"
#endif
@@ -66,37 +69,38 @@ AC_DEFUN([AC_CHECK_HEADER_STDBOOL],
"error: __bool_true_false_are_defined is not defined"
#endif
- struct s { _Bool s: 1; _Bool t; } s;
+ struct s { Bool s: 1; Bool t; bool u: 1; bool v; } s;
char a[true == 1 ? 1 : -1];
char b[false == 0 ? 1 : -1];
char c[__bool_true_false_are_defined == 1 ? 1 : -1];
char d[(bool) 0.5 == true ? 1 : -1];
/* See body of main program for 'e'. */
- char f[(_Bool) 0.0 == false ? 1 : -1];
+ char f[(Bool) 0.0 == false ? 1 : -1];
char g[true];
- char h[sizeof (_Bool)];
+ char h[sizeof (Bool)];
char i[sizeof s.t];
enum { j = false, k = true, l = false * true, m = true * 256 };
/* The following fails for
HP aC++/ANSI C B3910B A.05.55 [Dec 04 2003]. */
- _Bool n[m];
+ Bool n[m];
char o[sizeof n == m * sizeof n[0] ? 1 : -1];
- char p[-1 - (_Bool) 0 < 0 && -1 - (bool) 0 < 0 ? 1 : -1];
+ char p[-1 - (Bool) 0 < 0 && -1 - (bool) 0 < 0 ? 1 : -1];
/* Catch a bug in an HP-UX C compiler. See
http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html
http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html
*/
- _Bool q = true;
- _Bool *pq = &q;
+ Bool q = true;
+ Bool *pq = &q;
+ bool *qq = &q;
]],
[[
bool e = &s;
- *pq |= q;
- *pq |= ! q;
+ *pq |= q; *pq |= ! q;
+ *qq |= q; *qq |= ! q;
/* Refer to every declared value, to avoid compiler optimizations. */
return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !!j + !k + !!l
- + !m + !n + !o + !p + !q + !pq);
+ + !m + !n + !o + !p + !q + !pq + !qq);
]])],
[ac_cv_header_stdbool_h=yes],
[ac_cv_header_stdbool_h=no])])
--
2.5.5