1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* Copyright (C) 2001-2003, 2006-2013 Free Software Foundation, Inc.
4 Written by Bruno Haible <haible@clisp.cons.org>, 2001.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, see <http://www.gnu.org/licenses/>. */
22 /* ISO C 99 <stdbool.h> for platforms that lack it. */
26 Programs that use <stdbool.h> should be aware of some limitations
27 and standards compliance issues.
31 - <stdbool.h> must be #included before 'bool', 'false', 'true'
34 - You cannot assume that sizeof (bool) == 1.
36 - Programs should not undefine the macros bool, true, and false,
37 as C99 lists that as an "obsolescent feature".
39 Limitations of this substitute, when used in a C89 environment:
41 - <stdbool.h> must be #included before the '_Bool' type can be used.
43 - You cannot assume that _Bool is a typedef; it might be a macro.
45 - Bit-fields of type 'bool' are not supported. Portable code
46 should use 'unsigned int foo : 1;' rather than 'bool foo : 1;'.
48 - In C99, casts and automatic conversions to '_Bool' or 'bool' are
49 performed in such a way that every nonzero value gets converted
50 to 'true', and zero gets converted to 'false'. This doesn't work
51 with this substitute. With this substitute, only the values 0 and 1
52 give the expected result when converted to _Bool' or 'bool'.
54 - C99 allows the use of (_Bool)0.0 in constant expressions, but
55 this substitute cannot always provide this property.
57 Also, it is suggested that programs use 'bool' rather than '_Bool';
58 this isn't required, but 'bool' is more common. */
61 /* 7.16. Boolean type and values */
63 /* BeOS <sys/socket.h> already #defines false 0, true 1. We use the same
64 definitions below, but temporarily we have to #undef them. */
65 #if defined __BEOS__ && !defined __HAIKU__
66 # include <OS.h> /* defines bool but not _Bool */
75 # if defined __BEOS__ && !defined __HAIKU__
76 /* A compiler known to have 'bool'. */
77 /* If the compiler already has both 'bool' and '_Bool', we can assume they
78 are the same types. */
83 # if !defined __GNUC__
85 Some HP-UX cc and AIX IBM C compiler versions have compiler bugs when
86 the built-in _Bool type is used. See
87 http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html
88 http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html
89 http://lists.gnu.org/archive/html/bug-coreutils/2005-10/msg00086.html
90 Similar bugs are likely with other compilers as well; this file
91 wouldn't be used if <stdbool.h> was working.
92 So we override the _Bool type.
94 Need to define _Bool ourselves. As 'signed char' or as an enum type?
95 Use of a typedef, with SunPRO C, leads to a stupid
96 "warning: _Bool is a keyword in ISO C99".
97 Use of an enum type, with IRIX cc, leads to a stupid
98 "warning(1185): enumerated type mixed with another type".
99 Even the existence of an enum type, without a typedef,
100 "Invalid enumerator. (badenum)" with HP-UX cc on Tru64.
101 The only benefit of the enum, debuggability, is not important
102 with these compilers. So use 'signed char' and no enum. */
103 # define _Bool signed char
105 /* With this compiler, trust the _Bool type if the compiler has it. */
107 /* For the sake of symbolic names in gdb, define true and false as
108 enum constants, not only as macros.
109 It is tempting to write
110 typedef enum { false = 0, true = 1 } _Bool;
111 so that gdb prints values of type 'bool' symbolically. But then
112 values of type '_Bool' might promote to 'int' or 'unsigned int'
113 (see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int'
114 (see ISO C 99 6.3.1.1.(2)). So add a negative value to the
115 enum; this ensures that '_Bool' promotes to 'int'. */
116 typedef enum { _Bool_must_promote_to_int = -1, false = 0, true = 1 } _Bool;
123 /* The other macros must be usable in preprocessor directives. */
132 #define __bool_true_false_are_defined 1
134 #endif /* _GL_STDBOOL_H */