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/* ANSI and traditional C compatability macros
Copyright (C) 1991-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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 2 of the License, 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, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
/* ANSI and traditional C compatibility macros
ANSI C is assumed if __STDC__ is #defined.
Macro ANSI C definition Traditional C definition
----- ---- - ---------- ----------- - ----------
PTR `void *' `char *'
const not defined `'
volatile not defined `'
signed not defined `'
For ease of writing code which uses GCC extensions but needs to be
portable to other compilers, we provide the GCC_VERSION macro that
simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various
wrappers around __attribute__. Also, __extension__ will be #defined
to nothing if it doesn't work. See below. */
#ifndef _ANSIDECL_H
#define _ANSIDECL_H 1
#ifdef __cplusplus
extern "C" {
#endif
/* Every source file includes this file,
so they will all get the switch for lint. */
/* LINTLIBRARY */
/* Using MACRO(x,y) in cpp #if conditionals does not work with some
older preprocessors. Thus we can't define something like this:
#define HAVE_GCC_VERSION(MAJOR, MINOR) \
(__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR)))
and then test "#if HAVE_GCC_VERSION(2,7)".
So instead we use the macro below and test it against specific values. */
/* This macro simplifies testing whether we are using gcc, and if it
is of a particular minimum version. (Both major & minor numbers are
significant.) This macro will evaluate to 0 if we are not using
gcc at all. */
#ifndef GCC_VERSION
#define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
#endif /* GCC_VERSION */
#if defined (__STDC__) || defined(__cplusplus) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32)
/* All known AIX compilers implement these things (but don't always
define __STDC__). The RISC/OS MIPS compiler defines these things
in SVR4 mode, but does not define __STDC__. */
/* eraxxon@alumni.rice.edu: The Compaq C++ compiler, unlike many other
C++ compilers, does not define __STDC__, though it acts as if this
was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */
#define PTR void *
#undef const
#undef volatile
#undef signed
/* inline requires special treatment; it's in C99, and GCC >=2.7 supports
it too, but it's not in C89. */
#undef inline
#if __STDC_VERSION__ >= 199901L || defined(__cplusplus) || (defined(__SUNPRO_C) && defined(__C99FEATURES__))
/* it's a keyword */
#else
# if GCC_VERSION >= 2007
# define inline __inline__ /* __inline__ prevents -pedantic warnings */
# else
# define inline /* nothing */
# endif
#endif
#else /* Not ANSI C. */
#define PTR char *
/* some systems define these in header files for non-ansi mode */
#undef const
#undef volatile
#undef signed
#undef inline
#define const
#define volatile
#define signed
#define inline
#endif /* ANSI C. */
/* Define macros for some gcc attributes. This permits us to use the
macros freely, and know that they will come into play for the
version of gcc in which they are supported. */
#if (GCC_VERSION < 2007)
# define __attribute__(x)
#endif
/* Attribute __malloc__ on functions was valid as of gcc 2.96. */
#ifndef ATTRIBUTE_MALLOC
# if (GCC_VERSION >= 2096)
# define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
# else
# define ATTRIBUTE_MALLOC
# endif /* GNUC >= 2.96 */
#endif /* ATTRIBUTE_MALLOC */
/* Attributes on labels were valid as of gcc 2.93 and g++ 4.5. For
g++ an attribute on a label must be followed by a semicolon. */
#ifndef ATTRIBUTE_UNUSED_LABEL
# ifndef __cplusplus
# if GCC_VERSION >= 2093
# define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED
# else
# define ATTRIBUTE_UNUSED_LABEL
# endif
# else
# if GCC_VERSION >= 4005
# define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED ;
# else
# define ATTRIBUTE_UNUSED_LABEL
# endif
# endif
#endif
/* Similarly to ARG_UNUSED below. Prior to GCC 3.4, the C++ frontend
couldn't parse attributes placed after the identifier name, and now
the entire compiler is built with C++. */
#ifndef ATTRIBUTE_UNUSED
#if GCC_VERSION >= 3004
# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
#else
#define ATTRIBUTE_UNUSED
#endif
#endif /* ATTRIBUTE_UNUSED */
/* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the
identifier name. */
#if ! defined(__cplusplus) || (GCC_VERSION >= 3004)
# define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED
#else /* !__cplusplus || GNUC >= 3.4 */
# define ARG_UNUSED(NAME) NAME
#endif /* !__cplusplus || GNUC >= 3.4 */
#ifndef ATTRIBUTE_NORETURN
#define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
#endif /* ATTRIBUTE_NORETURN */
/* Attribute `nonnull' was valid as of gcc 3.3. */
#ifndef ATTRIBUTE_NONNULL
# if (GCC_VERSION >= 3003)
# define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m)))
# else
# define ATTRIBUTE_NONNULL(m)
# endif /* GNUC >= 3.3 */
#endif /* ATTRIBUTE_NONNULL */
/* Attribute `returns_nonnull' was valid as of gcc 4.9. */
#ifndef ATTRIBUTE_RETURNS_NONNULL
# if (GCC_VERSION >= 4009)
# define ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
# else
# define ATTRIBUTE_RETURNS_NONNULL
# endif /* GNUC >= 4.9 */
#endif /* ATTRIBUTE_RETURNS_NONNULL */
/* Attribute `pure' was valid as of gcc 3.0. */
#ifndef ATTRIBUTE_PURE
# if (GCC_VERSION >= 3000)
# define ATTRIBUTE_PURE __attribute__ ((__pure__))
# else
# define ATTRIBUTE_PURE
# endif /* GNUC >= 3.0 */
#endif /* ATTRIBUTE_PURE */
/* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL.
This was the case for the `printf' format attribute by itself
before GCC 3.3, but as of 3.3 we need to add the `nonnull'
attribute to retain this behavior. */
#ifndef ATTRIBUTE_PRINTF
#define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m)
#define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2)
#define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3)
#define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4)
#define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5)
#define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6)
#endif /* ATTRIBUTE_PRINTF */
/* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on
a function pointer. Format attributes were allowed on function
pointers as of gcc 3.1. */
#ifndef ATTRIBUTE_FPTR_PRINTF
# if (GCC_VERSION >= 3001)
# define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n)
# else
# define ATTRIBUTE_FPTR_PRINTF(m, n)
# endif /* GNUC >= 3.1 */
# define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2)
# define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3)
# define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4)
# define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5)
# define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6)
#endif /* ATTRIBUTE_FPTR_PRINTF */
/* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A
NULL format specifier was allowed as of gcc 3.3. */
#ifndef ATTRIBUTE_NULL_PRINTF
# if (GCC_VERSION >= 3003)
# define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n)))
# else
# define ATTRIBUTE_NULL_PRINTF(m, n)
# endif /* GNUC >= 3.3 */
# define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2)
# define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3)
# define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4)
# define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5)
# define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6)
#endif /* ATTRIBUTE_NULL_PRINTF */
/* Attribute `sentinel' was valid as of gcc 3.5. */
#ifndef ATTRIBUTE_SENTINEL
# if (GCC_VERSION >= 3005)
# define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__))
# else
# define ATTRIBUTE_SENTINEL
# endif /* GNUC >= 3.5 */
#endif /* ATTRIBUTE_SENTINEL */
#ifndef ATTRIBUTE_ALIGNED_ALIGNOF
# if (GCC_VERSION >= 3000)
# define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m))))
# else
# define ATTRIBUTE_ALIGNED_ALIGNOF(m)
# endif /* GNUC >= 3.0 */
#endif /* ATTRIBUTE_ALIGNED_ALIGNOF */
/* Useful for structures whose layout must much some binary specification
regardless of the alignment and padding qualities of the compiler. */
#ifndef ATTRIBUTE_PACKED
# define ATTRIBUTE_PACKED __attribute__ ((packed))
#endif
/* Attribute `hot' and `cold' was valid as of gcc 4.3. */
#ifndef ATTRIBUTE_COLD
# if (GCC_VERSION >= 4003)
# define ATTRIBUTE_COLD __attribute__ ((__cold__))
# else
# define ATTRIBUTE_COLD
# endif /* GNUC >= 4.3 */
#endif /* ATTRIBUTE_COLD */
#ifndef ATTRIBUTE_HOT
# if (GCC_VERSION >= 4003)
# define ATTRIBUTE_HOT __attribute__ ((__hot__))
# else
# define ATTRIBUTE_HOT
# endif /* GNUC >= 4.3 */
#endif /* ATTRIBUTE_HOT */
/* Attribute 'no_sanitize_undefined' was valid as of gcc 4.9. */
#ifndef ATTRIBUTE_NO_SANITIZE_UNDEFINED
# if (GCC_VERSION >= 4009)
# define ATTRIBUTE_NO_SANITIZE_UNDEFINED __attribute__ ((no_sanitize_undefined))
# else
# define ATTRIBUTE_NO_SANITIZE_UNDEFINED
# endif /* GNUC >= 4.9 */
#endif /* ATTRIBUTE_NO_SANITIZE_UNDEFINED */
/* We use __extension__ in some places to suppress -pedantic warnings
about GCC extensions. This feature didn't work properly before
gcc 2.8. */
#if GCC_VERSION < 2008
#define __extension__
#endif
/* This is used to declare a const variable which should be visible
outside of the current compilation unit. Use it as
EXPORTED_CONST int i = 1;
This is because the semantics of const are different in C and C++.
"extern const" is permitted in C but it looks strange, and gcc
warns about it when -Wc++-compat is not used. */
#ifdef __cplusplus
#define EXPORTED_CONST extern const
#else
#define EXPORTED_CONST const
#endif
/* Be conservative and only use enum bitfields with C++ or GCC.
FIXME: provide a complete autoconf test for buggy enum bitfields. */
#ifdef __cplusplus
#define ENUM_BITFIELD(TYPE) enum TYPE
#elif (GCC_VERSION > 2000)
#define ENUM_BITFIELD(TYPE) __extension__ enum TYPE
#else
#define ENUM_BITFIELD(TYPE) unsigned int
#endif
/* C++11 adds the ability to add "override" after an implementation of a
virtual function in a subclass, to:
(A) document that this is an override of a virtual function
(B) allow the compiler to issue a warning if it isn't (e.g. a mismatch
of the type signature).
Similarly, it allows us to add a "final" to indicate that no subclass
may subsequently override the vfunc.
Provide OVERRIDE and FINAL as macros, allowing us to get these benefits
when compiling with C++11 support, but without requiring C++11.
For gcc, use "-std=c++11" to enable C++11 support; gcc 6 onwards enables
this by default (actually GNU++14). */
#if __cplusplus >= 201103
/* C++11 claims to be available: use it. final/override were only
implemented in 4.7, though. */
# if GCC_VERSION < 4007
# define OVERRIDE
# define FINAL
# else
# define OVERRIDE override
# define FINAL final
# endif
#elif GCC_VERSION >= 4007
/* G++ 4.7 supports __final in C++98. */
# define OVERRIDE
# define FINAL __final
#else
/* No C++11 support; leave the macros empty: */
# define OVERRIDE
# define FINAL
#endif
#ifdef __cplusplus
}
#endif
#endif /* ansidecl.h */