Merge GDB 7.5.1

gdb/gnulib/import/stdbool.in.h

+/* Copyright (C) 2001-2003, 2006-2012 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
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef _GL_STDBOOL_H
+#define _GL_STDBOOL_H
+
+/* ISO C 99 <stdbool.h> for platforms that lack it.  */
+
+/* Usage suggestions:
+
+   Programs that use <stdbool.h> should be aware of some limitations
+   and standards compliance issues.
+
+   Standards compliance:
+
+       - <stdbool.h> must be #included before 'bool', 'false', 'true'
+         can be used.
+
+       - You cannot assume that sizeof (bool) == 1.
+
+       - Programs should not undefine the macros bool, true, and false,
+         as C99 lists that as an "obsolescent feature".
+
+   Limitations of this substitute, when used in a C89 environment:
+
+       - <stdbool.h> must be #included before the '_Bool' type can be used.
+
+       - You cannot assume that _Bool is a typedef; it might be a macro.
+
+       - Bit-fields of type 'bool' are not supported.  Portable code
+         should use 'unsigned int foo : 1;' rather than 'bool foo : 1;'.
+
+       - In C99, casts and automatic conversions to '_Bool' or 'bool' are
+         performed in such a way that every nonzero value gets converted
+         to 'true', and zero gets converted to 'false'.  This doesn't work
+         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 */
+
+/* BeOS <sys/socket.h> already #defines false 0, true 1.  We use the same
+   definitions below, but temporarily we have to #undef them.  */
+#if defined __BEOS__ && !defined __HAIKU__
+# include <OS.h> /* defines bool but not _Bool */
+# undef false
+# undef true
+#endif
+
+/* 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 || (defined __BEOS__ && !defined __HAIKU__)
+  /* A compiler known to have 'bool'.  */
+  /* If the compiler already has both 'bool' and '_Bool', we can assume they
+     are the same types.  */
+# if !@HAVE__BOOL@
+typedef bool _Bool;
+# endif
+#else
+# if !defined __GNUC__
+   /* 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
+# else
+   /* With this compiler, trust the _Bool type if the compiler has it.  */
+#  if !@HAVE__BOOL@
+typedef enum { _Bool_must_promote_to_int = -1, false = 0, true = 1 } _Bool;
+#  endif
+# endif
+#endif
+#define bool _Bool
+
+/* The other macros must be usable in preprocessor directives.  */
+#define false 0
+#define true 1
+#define __bool_true_false_are_defined 1
+
+#endif /* _GL_STDBOOL_H */