/* ANSI and traditional C compatability macros
- Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
- 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010
- Free Software Foundation, Inc.
+ Copyright (C) 1991-2019 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
Macro ANSI C definition Traditional C definition
----- ---- - ---------- ----------- - ----------
- ANSI_PROTOTYPES 1 not defined
PTR `void *' `char *'
- PTRCONST `void *const' `char *'
- LONG_DOUBLE `long double' `double'
const not defined `'
volatile not defined `'
signed not defined `'
- VA_START(ap, var) va_start(ap, var) va_start(ap)
-
- Note that it is safe to write "void foo();" indicating a function
- with no return value, in all K+R compilers we have been able to test.
-
- For declaring functions with prototypes, we also provide these:
-
- PARAMS ((prototype))
- -- for functions which take a fixed number of arguments. Use this
- when declaring the function. When defining the function, write a
- K+R style argument list. For example:
-
- char *strcpy PARAMS ((char *dest, char *source));
- ...
- char *
- strcpy (dest, source)
- char *dest;
- char *source;
- { ... }
-
-
- VPARAMS ((prototype, ...))
- -- for functions which take a variable number of arguments. Use
- PARAMS to declare the function, VPARAMS to define it. For example:
-
- int printf PARAMS ((const char *format, ...));
- ...
- int
- printf VPARAMS ((const char *format, ...))
- {
- ...
- }
-
- For writing functions which take variable numbers of arguments, we
- also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros. These
- hide the differences between K+R <varargs.h> and C89 <stdarg.h> more
- thoroughly than the simple VA_START() macro mentioned above.
-
- VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end.
- Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls
- corresponding to the list of fixed arguments. Then use va_arg
- normally to get the variable arguments, or pass your va_list object
- around. You do not declare the va_list yourself; VA_OPEN does it
- for you.
-
- Here is a complete example:
-
- int
- printf VPARAMS ((const char *format, ...))
- {
- int result;
-
- VA_OPEN (ap, format);
- VA_FIXEDARG (ap, const char *, format);
-
- result = vfprintf (stdout, format, ap);
- VA_CLOSE (ap);
-
- return result;
- }
-
-
- You can declare variables either before or after the VA_OPEN,
- VA_FIXEDARG sequence. Also, VA_OPEN and VA_CLOSE are the beginning
- and end of a block. They must appear at the same nesting level,
- and any variables declared after VA_OPEN go out of scope at
- VA_CLOSE. Unfortunately, with a K+R compiler, that includes the
- argument list. You can have multiple instances of VA_OPEN/VA_CLOSE
- pairs in a single function in case you need to traverse the
- argument list more than once.
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.
-
- This header also defines a lot of obsolete macros:
- CONST, VOLATILE, SIGNED, PROTO, EXFUN, DEFUN, DEFUN_VOID,
- AND, DOTS, NOARGS. Don't use them. */
+ to nothing if it doesn't work. See below. */
#ifndef _ANSIDECL_H
#define _ANSIDECL_H 1
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 ANSI_PROTOTYPES 1
#define PTR void *
-#define PTRCONST void *const
-#define LONG_DOUBLE long double
-/* PARAMS is often defined elsewhere (e.g. by libintl.h), so wrap it in
- a #ifndef. */
-#ifndef PARAMS
-#define PARAMS(ARGS) ARGS
-#endif
-
-#define VPARAMS(ARGS) ARGS
-#define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR)
-
-/* variadic function helper macros */
-/* "struct Qdmy" swallows the semicolon after VA_OPEN/VA_FIXEDARG's
- use without inhibiting further decls and without declaring an
- actual variable. */
-#define VA_OPEN(AP, VAR) { va_list AP; va_start(AP, VAR); { struct Qdmy
-#define VA_CLOSE(AP) } va_end(AP); }
-#define VA_FIXEDARG(AP, T, N) struct Qdmy
-
#undef const
#undef volatile
#undef signed
# endif
#endif
-/* These are obsolete. Do not use. */
-#ifndef IN_GCC
-#define CONST const
-#define VOLATILE volatile
-#define SIGNED signed
-
-#define PROTO(type, name, arglist) type name arglist
-#define EXFUN(name, proto) name proto
-#define DEFUN(name, arglist, args) name(args)
-#define DEFUN_VOID(name) name(void)
-#define AND ,
-#define DOTS , ...
-#define NOARGS void
-#endif /* ! IN_GCC */
-
#else /* Not ANSI C. */
-#undef ANSI_PROTOTYPES
#define PTR char *
-#define PTRCONST PTR
-#define LONG_DOUBLE double
-
-#define PARAMS(args) ()
-#define VPARAMS(args) (va_alist) va_dcl
-#define VA_START(va_list, var) va_start(va_list)
-
-#define VA_OPEN(AP, VAR) { va_list AP; va_start(AP); { struct Qdmy
-#define VA_CLOSE(AP) } va_end(AP); }
-#define VA_FIXEDARG(AP, TYPE, NAME) TYPE NAME = va_arg(AP, TYPE)
/* some systems define these in header files for non-ansi mode */
#undef const
#define signed
#define inline
-#ifndef IN_GCC
-#define CONST
-#define VOLATILE
-#define SIGNED
-
-#define PROTO(type, name, arglist) type name ()
-#define EXFUN(name, proto) name()
-#define DEFUN(name, arglist, args) name arglist args;
-#define DEFUN_VOID(name) name()
-#define AND ;
-#define DOTS
-#define NOARGS
-#endif /* ! IN_GCC */
-
#endif /* ANSI C. */
/* Define macros for some gcc attributes. This permits us to use the
# 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
-#define ATTRIBUTE_UNUSED __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
# 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)
# endif /* GNUC >= 3.0 */
#endif /* ATTRIBUTE_ALIGNED_ALIGNOF */
-/* Useful for structures whose layout must much some binary specification
+/* Useful for structures whose layout must match some binary specification
regardless of the alignment and padding qualities of the compiler. */
#ifndef ATTRIBUTE_PACKED
# define ATTRIBUTE_PACKED __attribute__ ((packed))
# 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 */
+
+/* Attribute 'nonstring' was valid as of gcc 8. */
+#ifndef ATTRIBUTE_NONSTRING
+# if GCC_VERSION >= 8000
+# define ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
+# else
+# define ATTRIBUTE_NONSTRING
+# endif
+#endif
+
/* We use __extension__ in some places to suppress -pedantic warnings
about GCC extensions. This feature didn't work properly before
gcc 2.8. */
#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
+
+#if __cpp_constexpr >= 200704
+#define CONSTEXPR constexpr
+#else
+#define CONSTEXPR
+#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 defined __cplusplus
+# 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
+#else
+ /* No C++11 support; leave the macros empty. */
+# define OVERRIDE
+# define FINAL
+#endif
+
+/* A macro to disable the copy constructor and assignment operator.
+ When building with C++11 and above, the methods are explicitly
+ deleted, causing a compile-time error if something tries to copy.
+ For C++03, this just declares the methods, causing a link-time
+ error if the methods end up called (assuming you don't
+ define them). For C++03, for best results, place the macro
+ under the private: access specifier, like this,
+
+ class name_lookup
+ {
+ private:
+ DISABLE_COPY_AND_ASSIGN (name_lookup);
+ };
+
+ so that most attempts at copy are caught at compile-time. */
+
+#if __cplusplus >= 201103
+#define DISABLE_COPY_AND_ASSIGN(TYPE) \
+ TYPE (const TYPE&) = delete; \
+ void operator= (const TYPE &) = delete
+ #else
+#define DISABLE_COPY_AND_ASSIGN(TYPE) \
+ TYPE (const TYPE&); \
+ void operator= (const TYPE &)
+#endif /* __cplusplus >= 201103 */
+
#ifdef __cplusplus
}
#endif