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-rw-r--r--lib/stdbool.mini.h80
1 files changed, 46 insertions, 34 deletions
diff --git a/lib/stdbool.mini.h b/lib/stdbool.mini.h
index cd36146f..c183f75a 100644
--- a/lib/stdbool.mini.h
+++ b/lib/stdbool.mini.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001-2003, 2006-2009 Free Software Foundation, Inc.
+/* Copyright (C) 2001-2003, 2006-2017 Free Software Foundation, Inc.
Written by Bruno Haible <haible@clisp.cons.org>, 2001.
This program is free software; you can redistribute it and/or modify
@@ -49,50 +49,62 @@
with this substitute. With this substitute, only the values 0 and 1
give the expected result when converted to _Bool' or 'bool'.
+ - C99 allows the use of (_Bool)0.0 in constant expressions, but
+ this substitute cannot always provide this property.
+
Also, it is suggested that programs use 'bool' rather than '_Bool';
this isn't required, but 'bool' is more common. */
/* 7.16. Boolean type and values */
-/* For the sake of symbolic names in gdb, we define true and false as
- enum constants, not only as macros.
- It is tempting to write
- typedef enum { false = 0, true = 1 } _Bool;
- so that gdb prints values of type 'bool' symbolically. But if we do
- this, values of type '_Bool' may promote to 'int' or 'unsigned int'
- (see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int'
- (see ISO C 99 6.3.1.1.(2)). So we add a negative value to the
- enum; this ensures that '_Bool' promotes to 'int'. */
-#if defined __cplusplus
+#ifdef __cplusplus
/* Assume the compiler has 'bool' and '_Bool'. */
#else
- /* If @HAVE__BOOL@:
- Some HP-UX cc and AIX IBM C compiler versions have compiler bugs when
- the built-in _Bool type is used. See
- http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html
- http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html
- http://lists.gnu.org/archive/html/bug-coreutils/2005-10/msg00086.html
- Similar bugs are likely with other compilers as well; this file
- wouldn't be used if <stdbool.h> was working.
- So we override the _Bool type.
- If !@HAVE__BOOL@:
- Need to define _Bool ourselves. As 'signed char' or as an enum type?
- Use of a typedef, with SunPRO C, leads to a stupid
- "warning: _Bool is a keyword in ISO C99".
- Use of an enum type, with IRIX cc, leads to a stupid
- "warning(1185): enumerated type mixed with another type".
- Even the existence of an enum type, without a typedef,
- "Invalid enumerator. (badenum)" with HP-UX cc on Tru64.
- The only benefit of the enum, debuggability, is not important
- with these compilers. So use 'signed char' and no enum. */
-# define _Bool signed char
+ /* <stdbool.h> is known to exist and work with the following compilers:
+ - GNU C 3.0 or newer, on any platform,
+ - Intel C,
+ - MSVC 12 (Visual Studio 2013) or newer,
+ - Sun C, on Solaris, if _STDC_C99 is defined,
+ - AIX xlc, if _ANSI_C_SOURCE is defined,
+ - HP C, on HP-UX 11.31 or newer.
+ It is know not to work with:
+ - Sun C, on Solaris, if __C99FEATURES__ is defined but _STDC_C99 is not,
+ - MIPSpro C 7.30, on IRIX. */
+# if (__GNUC__ >= 3) \
+ || defined __INTEL_COMPILER \
+ || (_MSC_VER >= 1800) \
+ || (defined __SUNPRO_C && defined _STDC_C99) \
+ || (defined _AIX && !defined __GNUC__ && defined _ANSI_C_SOURCE) \
+ || defined __HP_cc
+ /* Assume the compiler has <stdbool.h>. */
+# include <stdbool.h>
+# else
+ /* Need to define _Bool ourselves. As 'signed char' or as an enum type?
+ Use of a typedef, with SunPRO C, leads to a stupid
+ "warning: _Bool is a keyword in ISO C99".
+ Use of an enum type, with IRIX cc, leads to a stupid
+ "warning(1185): enumerated type mixed with another type".
+ Even the existence of an enum type, without a typedef,
+ "Invalid enumerator. (badenum)" with HP-UX cc on Tru64.
+ The only benefit of the enum, debuggability, is not important
+ with these compilers. So use 'signed char' and no enum. */
+# define _Bool signed char
+# define bool _Bool
+# endif
#endif
-#define bool _Bool
/* The other macros must be usable in preprocessor directives. */
-#define false 0
-#define true 1
+#ifdef __cplusplus
+# define false false
+# define true true
+#else
+# undef false
+# define false 0
+# undef true
+# define true 1
+#endif
+
#define __bool_true_false_are_defined 1
#endif /* _UNISTRING_STDBOOL_H */