-/* Copyright (C) 1992, 93, 94, 95, 96, 97 Free Software Foundation, Inc.
+/* Copyright (C) 1992,93,94,95,96,97,98,99, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
Boston, MA 02111-1307, USA. */
#ifndef _SYS_CDEFS_H
-
#define _SYS_CDEFS_H 1
-#include <features.h>
+
+/* We are almost always included from features.h. */
+#ifndef _FEATURES_H
+# include <features.h>
+#endif
+
+/* The GNU libc does not support any K&R compilers or the traditional mode
+ of ISO C compilers anymore. Check for some of the combinations not
+ anymore supported. */
+#if defined __GNUC__ && !defined __STDC__
+# error "You need a ISO C conforming compiler to use the glibc headers"
+#endif
/* Some user header file might have defined this before. */
#undef __P
+#undef __PMT
#ifdef __GNUC__
-#define __P(args) args /* GCC can always grok prototypes. */
-#define __DOTS , ...
+/* GCC can always grok prototypes. For C++ programs we add throw()
+ to help it optimize the function calls. But this works only with
+ gcc 2.8.x and egcs. */
+# if defined __cplusplus && __GNUC_PREREQ (2,8)
+# define __THROW throw ()
+# else
+# define __THROW
+# endif
+# define __P(args) args __THROW
+/* This macro will be used for functions which might take C++ callback
+ functions. */
+# define __PMT(args) args
#else /* Not GCC. */
-#define __inline /* No inline functions. */
-
-#if (defined (__STDC__) && __STDC__) || defined (__cplusplus)
-
-#define __P(args) args
-#define __const const
-#define __signed signed
-#define __volatile volatile
-#define __DOTS , ...
-
-#else /* Not ANSI C or C++. */
+# define __inline /* No inline functions. */
-#define __P(args) () /* No prototypes. */
-#define __const /* No ANSI C keywords. */
-#define __signed
-#define __volatile
-#define __DOTS
+# define __THROW
+# define __P(args) args
+# define __PMT(args) args
-#endif /* ANSI C or C++. */
+# define __const const
+# define __signed signed
+# define __volatile volatile
#endif /* GCC. */
/* For these things, GCC behaves the ANSI way normally,
and the non-ANSI way under -traditional. */
-#if defined (__STDC__) && __STDC__
-
-#define __CONCAT(x,y) x ## y
-#define __STRING(x) #x
+#define __CONCAT(x,y) x ## y
+#define __STRING(x) #x
/* This is not a typedef so `const __ptr_t' does the right thing. */
#define __ptr_t void *
#define __long_double_t long double
+
+/* C++ needs to know that types and declarations are C, not C++. */
+#ifdef __cplusplus
+# define __BEGIN_DECLS extern "C" {
+# define __END_DECLS }
#else
+# define __BEGIN_DECLS
+# define __END_DECLS
+#endif
-#define __CONCAT(x,y) x/**/y
-#define __STRING(x) "x"
-#define __ptr_t char *
-#define __long_double_t long double
+/* Support for bounded pointers. */
+#ifndef __BOUNDED_POINTERS__
+# define __bounded /* nothing */
+# define __unbounded /* nothing */
+# define __ptrvalue /* nothing */
+#endif
+
-/* The BSD header files use the ANSI keywords unmodified (this means that
- old programs may lose if they use the new keywords as identifiers), but
- those names are not available under -traditional. We define them to
- their __ versions, which are taken care of above. */
-#ifdef __USE_BSD
-#define const __const
-#define signed __signed
-#define volatile __volatile
+/* __asm__ ("xyz") is used throughout the headers to rename functions
+ at the assembly language level. This is wrapped by the __REDIRECT
+ macro, in order to support compilers that can do this some other
+ way. When compilers don't support asm-names at all, we have to do
+ preprocessor tricks instead (which don't have exactly the right
+ semantics, but it's the best we can do).
+
+ Example:
+ int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
+
+#if defined __GNUC__ && __GNUC__ >= 2
+
+# define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
+# define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
+# define __ASMNAME2(prefix, cname) __STRING (prefix) cname
+
+/*
+#elif __SOME_OTHER_COMPILER__
+
+# define __REDIRECT(name, proto, alias) name proto; \
+ _Pragma("let " #name " = " #alias)
+*/
+#endif
+
+/* GCC has various useful declarations that can be made with the
+ `__attribute__' syntax. All of the ways we use this do fine if
+ they are omitted for compilers that don't understand it. */
+#if !defined __GNUC__ || __GNUC__ < 2
+# define __attribute__(xyz) /* Ignore */
#endif
-#endif /* __STDC__ */
+/* At some point during the gcc 2.96 development the `malloc' attribute
+ for functions was introduced. We don't want to use it unconditionally
+ (although this would be possible) since it generates warnings. */
+#if __GNUC_PREREQ (2,96)
+# define __attribute_malloc__ __attribute__ ((__malloc__))
+#else
+# define __attribute_malloc__ /* Ignore */
+#endif
+/* At some point during the gcc 2.96 development the `pure' attribute
+ for functions was introduced. We don't want to use it unconditionally
+ (although this would be possible) since it generates warnings. */
+#if __GNUC_PREREQ (2,96)
+# define __attribute_pure__ __attribute__ ((__pure__))
+#else
+# define __attribute_pure__ /* Ignore */
+#endif
-/* C++ needs to know that types and declarations are C, not C++. */
-#ifdef __cplusplus
-#define __BEGIN_DECLS extern "C" {
-#define __END_DECLS }
+/* At some point during the gcc 2.8 development the `format_arg' attribute
+ for functions was introduced. We don't want to use it unconditionally
+ (although this would be possible) since it generates warnings. */
+#if __GNUC_PREREQ (2,8)
+# define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
#else
-#define __BEGIN_DECLS
-#define __END_DECLS
+# define __attribute_format_arg__(x) /* Ignore */
#endif
-/* GCC2 has various useful declarations that can be made with the
- `__attribute__' syntax. All of the ways we use this do fine if
- they are omitted for compilers that don't understand it. */
-#if !defined (__GNUC__) || __GNUC__ < 2
-#define __attribute__(xyz) /* Ignore. */
+/* It is possible to compile containing GCC extensions even if GCC is
+ run in pedantic mode if the uses are carefully marked using the
+ `__extension__' keyword. But this is not generally available before
+ version 2.8. */
+#if !__GNUC_PREREQ (2,8)
+# define __extension__ /* Ignore */
#endif
+/* __restrict is known in EGCS 1.2 and above. */
+#if !__GNUC_PREREQ (2,92)
+# define __restrict /* Ignore */
+#endif
-/* For now no version of gcc knows the `restrict' keyword. Define it
- for now unconditionally to the empty string. */
-#define __restrict
+/* ISO C99 also allows to declare arrays as non-overlapping. The syntax is
+ array_name[restrict]
+ But gcc so far does not support this syntax. We define a separate macro
+ for this which can be enabled if the underlying compiler supports it. */
+#define __restrict_arr
#endif /* sys/cdefs.h */
projects / platform / upstream / glibc.git / blobdiff