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1# Check for stdbool.h that conforms to C99.
2
f61aad93 3# Copyright (C) 2002-2003 Free Software Foundation, Inc.
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4
5# This program is free software; you can redistribute it and/or modify
6# it under the terms of the GNU General Public License as published by
7# the Free Software Foundation; either version 2, or (at your option)
8# any later version.
9
10# This program is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13# GNU General Public License for more details.
14
15# You should have received a copy of the GNU General Public License
16# along with this program; if not, write to the Free Software
17# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
18# 02111-1307, USA.
19
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20# Prepare for substituting <stdbool.h> if it is not supported.
21
22AC_DEFUN([AM_STDBOOL_H],
23[
24 AC_REQUIRE([AC_HEADER_STDBOOL])
25
26 # Define two additional variables used in the Makefile substitution.
27
28 if test "$ac_cv_header_stdbool_h" = yes; then
29 STDBOOL_H=''
30 else
31 STDBOOL_H='stdbool.h'
32 fi
33 AC_SUBST([STDBOOL_H])
34
35 if test "$ac_cv_type__Bool" = yes; then
36 HAVE__BOOL=1
37 else
38 HAVE__BOOL=0
39 fi
40 AC_SUBST([HAVE__BOOL])
41])
42
43# This macro is only needed in autoconf <= 2.54. Newer versions of autoconf
44# have this macro built-in.
45
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46AC_DEFUN([AC_HEADER_STDBOOL],
47 [AC_CACHE_CHECK([for stdbool.h that conforms to C99],
48 [ac_cv_header_stdbool_h],
49 [AC_TRY_COMPILE(
50 [
51 #include <stdbool.h>
52 #ifndef bool
53 "error: bool is not defined"
54 #endif
55 #ifndef false
56 "error: false is not defined"
57 #endif
58 #if false
59 "error: false is not 0"
60 #endif
61 #ifndef true
62 "error: false is not defined"
63 #endif
64 #if true != 1
65 "error: true is not 1"
66 #endif
67 #ifndef __bool_true_false_are_defined
68 "error: __bool_true_false_are_defined is not defined"
69 #endif
70
71 struct s { _Bool s: 1; _Bool t; } s;
72
73 char a[true == 1 ? 1 : -1];
74 char b[false == 0 ? 1 : -1];
75 char c[__bool_true_false_are_defined == 1 ? 1 : -1];
76 char d[(bool) -0.5 == true ? 1 : -1];
77 bool e = &s;
78 char f[(_Bool) -0.0 == false ? 1 : -1];
79 char g[true];
80 char h[sizeof (_Bool)];
81 char i[sizeof s.t];
82 ],
83 [ return !a + !b + !c + !d + !e + !f + !g + !h + !i; ],
84 [ac_cv_header_stdbool_h=yes],
85 [ac_cv_header_stdbool_h=no])])
f61aad93 86 AC_CHECK_TYPES([_Bool])
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87 if test $ac_cv_header_stdbool_h = yes; then
88 AC_DEFINE(HAVE_STDBOOL_H, 1, [Define to 1 if stdbool.h conforms to C99.])
89 fi])