1 /* -*- buffer-read-only: t -*- vi: set ro: */ 2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */ 3 /* Copyright (C) 2001-2003, 2006-2008 Free Software Foundation, Inc. 4 Written by Bruno Haible <haible (at) clisp.cons.org>, 2001. 5 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) 9 any later version. 10 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. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software Foundation, 18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 #ifndef _GL_STDBOOL_H 21 #define _GL_STDBOOL_H 22 23 /* ISO C 99 <stdbool.h> for platforms that lack it. */ 24 25 /* Usage suggestions: 26 27 Programs that use <stdbool.h> should be aware of some limitations 28 and standards compliance issues. 29 30 Standards compliance: 31 32 - <stdbool.h> must be #included before 'bool', 'false', 'true' 33 can be used. 34 35 - You cannot assume that sizeof (bool) == 1. 36 37 - Programs should not undefine the macros bool, true, and false, 38 as C99 lists that as an "obsolescent feature". 39 40 Limitations of this substitute, when used in a C89 environment: 41 42 - <stdbool.h> must be #included before the '_Bool' type can be used. 43 44 - You cannot assume that _Bool is a typedef; it might be a macro. 45 46 - Bit-fields of type 'bool' are not supported. Portable code 47 should use 'unsigned int foo : 1;' rather than 'bool foo : 1;'. 48 49 - In C99, casts and automatic conversions to '_Bool' or 'bool' are 50 performed in such a way that every nonzero value gets converted 51 to 'true', and zero gets converted to 'false'. This doesn't work 52 with this substitute. With this substitute, only the values 0 and 1 53 give the expected result when converted to _Bool' or 'bool'. 54 55 Also, it is suggested that programs use 'bool' rather than '_Bool'; 56 this isn't required, but 'bool' is more common. */ 57 58 59 /* 7.16. Boolean type and values */ 60 61 /* BeOS <sys/socket.h> already #defines false 0, true 1. We use the same 62 definitions below, but temporarily we have to #undef them. */ 63 #if defined __BEOS__ && !defined __HAIKU__ 64 # include <OS.h> /* defines bool but not _Bool */ 65 # undef false 66 # undef true 67 #endif 68 69 /* For the sake of symbolic names in gdb, we define true and false as 70 enum constants, not only as macros. 71 It is tempting to write 72 typedef enum { false = 0, true = 1 } _Bool; 73 so that gdb prints values of type 'bool' symbolically. But if we do 74 this, values of type '_Bool' may promote to 'int' or 'unsigned int' 75 (see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int' 76 (see ISO C 99 6.3.1.1.(2)). So we add a negative value to the 77 enum; this ensures that '_Bool' promotes to 'int'. */ 78 #if defined __cplusplus || (defined __BEOS__ && !defined __HAIKU__) 79 /* A compiler known to have 'bool'. */ 80 /* If the compiler already has both 'bool' and '_Bool', we can assume they 81 are the same types. */ 82 # if !@HAVE__BOOL@ 83 typedef bool _Bool; 84 # endif 85 #else 86 # if !defined __GNUC__ 87 /* If @HAVE__BOOL@: 88 Some HP-UX cc and AIX IBM C compiler versions have compiler bugs when 89 the built-in _Bool type is used. See 90 http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html 91 http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html 92 http://lists.gnu.org/archive/html/bug-coreutils/2005-10/msg00086.html 93 Similar bugs are likely with other compilers as well; this file 94 wouldn't be used if <stdbool.h> was working. 95 So we override the _Bool type. 96 If !@HAVE__BOOL@: 97 Need to define _Bool ourselves. As 'signed char' or as an enum type? 98 Use of a typedef, with SunPRO C, leads to a stupid 99 "warning: _Bool is a keyword in ISO C99". 100 Use of an enum type, with IRIX cc, leads to a stupid 101 "warning(1185): enumerated type mixed with another type". 102 Even the existence of an enum type, without a typedef, 103 "Invalid enumerator. (badenum)" with HP-UX cc on Tru64. 104 The only benefit of the enum, debuggability, is not important 105 with these compilers. So use 'signed char' and no enum. */ 106 # define _Bool signed char 107 # else 108 /* With this compiler, trust the _Bool type if the compiler has it. */ 109 # if !@HAVE__BOOL@ 110 typedef enum { _Bool_must_promote_to_int = -1, false = 0, true = 1 } _Bool; 111 # endif 112 # endif 113 #endif 114 #define bool _Bool 115 116 /* The other macros must be usable in preprocessor directives. */ 117 #define false 0 118 #define true 1 119 #define __bool_true_false_are_defined 1 120 121 #endif /* _GL_STDBOOL_H */ 122
