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Editing: cdefs.h
/* Copyright (C) 1992-2018 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 modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #ifndef _SYS_CDEFS_H #define _SYS_CDEFS_H 1 /* 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__ /* All functions, except those with callbacks or those that synchronize memory, are leaf functions. */ # if __GNUC_PREREQ (4, 6) && !defined _LIBC # define __LEAF , __leaf__ # define __LEAF_ATTR __attribute__ ((__leaf__)) # else # define __LEAF # define __LEAF_ATTR # endif /* 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. For gcc 3.2 and up we even mark C functions as non-throwing using a function attribute since programs can use the -fexceptions options for C code as well. */ # if !defined __cplusplus && __GNUC_PREREQ (3, 3) # define __THROW __attribute__ ((__nothrow__ __LEAF)) # define __THROWNL __attribute__ ((__nothrow__)) # define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct # define __NTHNL(fct) __attribute__ ((__nothrow__)) fct # else # if defined __cplusplus && __GNUC_PREREQ (2,8) # define __THROW throw () # define __THROWNL throw () # define __NTH(fct) __LEAF_ATTR fct throw () # define __NTHNL(fct) fct throw () # else # define __THROW # define __THROWNL # define __NTH(fct) fct # define __NTHNL(fct) fct # endif # endif #else /* Not GCC. */ # if (defined __cplusplus \ || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) # define __inline inline # else # define __inline /* No inline functions. */ # endif # define __THROW # define __THROWNL # define __NTH(fct) fct #endif /* GCC. */ /* Compilers that are not clang may object to #if defined __clang__ && __has_extension(...) even though they do not need to evaluate the right-hand side of the &&. */ #if defined __clang__ && defined __has_extension # define __glibc_clang_has_extension(ext) __has_extension (ext) #else # define __glibc_clang_has_extension(ext) 0 #endif /* These two macros are not used in glibc anymore. They are kept here only because some other projects expect the macros to be defined. */ #define __P(args) args #define __PMT(args) args /* For these things, GCC behaves the ANSI way normally, and the non-ANSI way under -traditional. */ #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 * /* 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 /* Fortify support. */ #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1) #define __bos0(ptr) __builtin_object_size (ptr, 0) /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */ #if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0) \ || __GNUC_PREREQ (12, 0)) # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0) # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1) #else # define __glibc_objsize0(__o) __bos0 (__o) # define __glibc_objsize(__o) __bos (__o) #endif #if __USE_FORTIFY_LEVEL > 0 /* Compile time conditions to choose between the regular, _chk and _chk_warn variants. These conditions should get evaluated to constant and optimized away. */ #define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s)) #define __glibc_unsigned_or_positive(__l) \ ((__typeof (__l)) 0 < (__typeof (__l)) -1 \ || (__builtin_constant_p (__l) && (__l) > 0)) /* Length is known to be safe at compile time if the __L * __S <= __OBJSZ condition can be folded to a constant and if it is true, or unknown (-1) */ #define __glibc_safe_or_unknown_len(__l, __s, __osz) \ ((__builtin_constant_p (__osz) && (__osz) == (__SIZE_TYPE__) -1) \ || (__glibc_unsigned_or_positive (__l) \ && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \ (__s), (__osz))) \ && __glibc_safe_len_cond ((__SIZE_TYPE__) (__l), (__s), (__osz)))) /* Conversely, we know at compile time that the length is unsafe if the __L * __S <= __OBJSZ condition can be folded to a constant and if it is false. */ #define __glibc_unsafe_len(__l, __s, __osz) \ (__glibc_unsigned_or_positive (__l) \ && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \ __s, __osz)) \ && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz)) /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be declared. */ #define __glibc_fortify(f, __l, __s, __osz, ...) \ (__glibc_safe_or_unknown_len (__l, __s, __osz) \ ? __ ## f ## _alias (__VA_ARGS__) \ : (__glibc_unsafe_len (__l, __s, __osz) \ ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \ : __ ## f ## _chk (__VA_ARGS__, __osz))) /* Fortify function f, where object size argument passed to f is the number of elements and not total size. */ #define __glibc_fortify_n(f, __l, __s, __osz, ...) \ (__glibc_safe_or_unknown_len (__l, __s, __osz) \ ? __ ## f ## _alias (__VA_ARGS__) \ : (__glibc_unsafe_len (__l, __s, __osz) \ ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \ : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) #endif #if __GNUC_PREREQ (4,3) # define __warndecl(name, msg) \ extern void name (void) __attribute__((__warning__ (msg))) # define __warnattr(msg) __attribute__((__warning__ (msg))) # define __errordecl(name, msg) \ extern void name (void) __attribute__((__error__ (msg))) #else # define __warndecl(name, msg) extern void name (void) # define __warnattr(msg) # define __errordecl(name, msg) extern void name (void) #endif /* Support for flexible arrays. Headers that should use flexible arrays only if they're "real" (e.g. only if they won't affect sizeof()) should test #if __glibc_c99_flexarr_available. */ #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L # define __flexarr [] # define __glibc_c99_flexarr_available 1 #elif __GNUC_PREREQ (2,97) /* GCC 2.97 supports C99 flexible array members as an extension, even when in C89 mode or compiling C++ (any version). */ # define __flexarr [] # define __glibc_c99_flexarr_available 1 #elif defined __GNUC__ /* Pre-2.97 GCC did not support C99 flexible arrays but did have an equivalent extension with slightly different notation. */ # define __flexarr [0] # define __glibc_c99_flexarr_available 1 #else /* Some other non-C99 compiler. Approximate with [1]. */ # define __flexarr [1] # define __glibc_c99_flexarr_available 0 #endif /* __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)) # ifdef __cplusplus # define __REDIRECT_NTH(name, proto, alias) \ name proto __THROW __asm__ (__ASMNAME (#alias)) # define __REDIRECT_NTHNL(name, proto, alias) \ name proto __THROWNL __asm__ (__ASMNAME (#alias)) # else # define __REDIRECT_NTH(name, proto, alias) \ name proto __asm__ (__ASMNAME (#alias)) __THROW # define __REDIRECT_NTHNL(name, proto, alias) \ name proto __asm__ (__ASMNAME (#alias)) __THROWNL # endif # 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 /* 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 /* Tell the compiler which arguments to an allocation function indicate the size of the allocation. */ #if __GNUC_PREREQ (4, 3) # define __attribute_alloc_size__(params) \ __attribute__ ((__alloc_size__ params)) #else # define __attribute_alloc_size__(params) /* 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 /* This declaration tells the compiler that the value is constant. */ #if __GNUC_PREREQ (2,5) # define __attribute_const__ __attribute__ ((__const__)) #else # define __attribute_const__ /* Ignore */ #endif /* At some point during the gcc 3.1 development the `used' 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 (3,1) # define __attribute_used__ __attribute__ ((__used__)) # define __attribute_noinline__ __attribute__ ((__noinline__)) #else # define __attribute_used__ __attribute__ ((__unused__)) # define __attribute_noinline__ /* Ignore */ #endif /* Since version 3.2, gcc allows marking deprecated functions. */ #if __GNUC_PREREQ (3,2) # define __attribute_deprecated__ __attribute__ ((__deprecated__)) #else # define __attribute_deprecated__ /* Ignore */ #endif /* Since version 4.5, gcc also allows one to specify the message printed when a deprecated function is used. clang claims to be gcc 4.2, but may also support this feature. */ #if __GNUC_PREREQ (4,5) || \ __glibc_clang_has_extension (__attribute_deprecated_with_message__) # define __attribute_deprecated_msg__(msg) \ __attribute__ ((__deprecated__ (msg))) #else # define __attribute_deprecated_msg__(msg) __attribute_deprecated__ #endif /* 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 several `format_arg' attributes are given for the same function, in gcc-3.0 and older, all but the last one are ignored. In newer gccs, all designated arguments are considered. */ #if __GNUC_PREREQ (2,8) # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x))) #else # define __attribute_format_arg__(x) /* Ignore */ #endif /* At some point during the gcc 2.97 development the `strfmon' format 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 (2,97) # define __attribute_format_strfmon__(a,b) \ __attribute__ ((__format__ (__strfmon__, a, b))) #else # define __attribute_format_strfmon__(a,b) /* Ignore */ #endif /* The nonull function attribute allows to mark pointer parameters which must not be NULL. */ #if __GNUC_PREREQ (3,3) # define __nonnull(params) __attribute__ ((__nonnull__ params)) #else # define __nonnull(params) #endif /* If fortification mode, we warn about unused results of certain function calls which can lead to problems. */ #if __GNUC_PREREQ (3,4) # define __attribute_warn_unused_result__ \ __attribute__ ((__warn_unused_result__)) # if __USE_FORTIFY_LEVEL > 0 # define __wur __attribute_warn_unused_result__ # endif #else # define __attribute_warn_unused_result__ /* empty */ #endif #ifndef __wur # define __wur /* Ignore */ #endif /* Forces a function to be always inlined. */ #if __GNUC_PREREQ (3,2) /* The Linux kernel defines __always_inline in stddef.h (283d7573), and it conflicts with this definition. Therefore undefine it first to allow either header to be included first. */ # undef __always_inline # define __always_inline __inline __attribute__ ((__always_inline__)) #else # undef __always_inline # define __always_inline __inline #endif /* Associate error messages with the source location of the call site rather than with the source location inside the function. */ #if __GNUC_PREREQ (4,3) # define __attribute_artificial__ __attribute__ ((__artificial__)) #else # define __attribute_artificial__ /* Ignore */ #endif /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99 inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__ or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions older than 4.3 may define these macros and still not guarantee GNU inlining semantics. clang++ identifies itself as gcc-4.2, but has support for GNU inlining semantics, that can be checked fot by using the __GNUC_STDC_INLINE_ and __GNUC_GNU_INLINE__ macro definitions. */ #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \ || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \ || defined __GNUC_GNU_INLINE__))) # if defined __GNUC_STDC_INLINE__ || defined __cplusplus # define __extern_inline extern __inline __attribute__ ((__gnu_inline__)) # define __extern_always_inline \ extern __always_inline __attribute__ ((__gnu_inline__)) # else # define __extern_inline extern __inline # define __extern_always_inline extern __always_inline # endif #endif #ifdef __extern_always_inline # define __fortify_function __extern_always_inline __attribute_artificial__ #endif /* GCC 4.3 and above allow passing all anonymous arguments of an __extern_always_inline function to some other vararg function. */ #if __GNUC_PREREQ (4,3) # define __va_arg_pack() __builtin_va_arg_pack () # define __va_arg_pack_len() __builtin_va_arg_pack_len () #endif /* 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) # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L # define __restrict restrict # else # define __restrict /* Ignore */ # endif #endif /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is array_name[restrict] GCC 3.1 supports this. */ #if __GNUC_PREREQ (3,1) && !defined __GNUG__ # define __restrict_arr __restrict #else # ifdef __GNUC__ # define __restrict_arr /* Not supported in old GCC. */ # else # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L # define __restrict_arr restrict # else /* Some other non-C99 compiler. */ # define __restrict_arr /* Not supported. */ # endif # endif #endif #if __GNUC__ >= 3 # define __glibc_unlikely(cond) __builtin_expect ((cond), 0) # define __glibc_likely(cond) __builtin_expect ((cond), 1) #else # define __glibc_unlikely(cond) (cond) # define __glibc_likely(cond) (cond) #endif #ifdef __has_attribute # define __glibc_has_attribute(attr) __has_attribute (attr) #else # define __glibc_has_attribute(attr) 0 #endif #if (!defined _Noreturn \ && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ && !__GNUC_PREREQ (4,7)) # if __GNUC_PREREQ (2,8) # define _Noreturn __attribute__ ((__noreturn__)) # else # define _Noreturn # endif #endif #if __GNUC_PREREQ (8, 0) /* Describes a char array whose address can safely be passed as the first argument to strncpy and strncat, as the char array is not necessarily a NUL-terminated string. */ # define __attribute_nonstring__ __attribute__ ((__nonstring__)) #else # define __attribute_nonstring__ #endif #if (!defined _Static_assert && !defined __cplusplus \ && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ && (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__)) # define _Static_assert(expr, diagnostic) \ extern int (*__Static_assert_function (void)) \ [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })] #endif #include <bits/wordsize.h> #include <bits/long-double.h> #if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH # define __LDBL_COMPAT 1 # ifdef __REDIRECT # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias) # define __LDBL_REDIR(name, proto) \ __LDBL_REDIR1 (name, proto, __nldbl_##name) # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias) # define __LDBL_REDIR_NTH(name, proto) \ __LDBL_REDIR1_NTH (name, proto, __nldbl_##name) # define __LDBL_REDIR1_DECL(name, alias) \ extern __typeof (name) name __asm (__ASMNAME (#alias)); # define __LDBL_REDIR_DECL(name) \ extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name)); # define __REDIRECT_LDBL(name, proto, alias) \ __LDBL_REDIR1 (name, proto, __nldbl_##alias) # define __REDIRECT_NTH_LDBL(name, proto, alias) \ __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias) # endif #endif #if !defined __LDBL_COMPAT || !defined __REDIRECT # define __LDBL_REDIR1(name, proto, alias) name proto # define __LDBL_REDIR(name, proto) name proto # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW # define __LDBL_REDIR_NTH(name, proto) name proto __THROW # define __LDBL_REDIR_DECL(name) # ifdef __REDIRECT # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias) # define __REDIRECT_NTH_LDBL(name, proto, alias) \ __REDIRECT_NTH (name, proto, alias) # endif #endif /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is intended for use in preprocessor macros. Note: MESSAGE must be a _single_ string; concatenation of string literals is not supported. */ #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5) # define __glibc_macro_warning1(message) _Pragma (#message) # define __glibc_macro_warning(message) \ __glibc_macro_warning1 (GCC warning message) #else # define __glibc_macro_warning(msg) #endif /* Generic selection (ISO C11) is a C-only feature, available in GCC since version 4.9. Previous versions do not provide generic selection, even though they might set __STDC_VERSION__ to 201112L, when in -std=c11 mode. Thus, we must check for !defined __GNUC__ when testing __STDC_VERSION__ for generic selection support. On the other hand, Clang also defines __GNUC__, so a clang-specific check is required to enable the use of generic selection. */ #if !defined __cplusplus \ && (__GNUC_PREREQ (4, 9) \ || __glibc_clang_has_extension (c_generic_selections) \ || (!defined __GNUC__ && defined __STDC_VERSION__ \ && __STDC_VERSION__ >= 201112L)) # define __HAVE_GENERIC_SELECTION 1 #else # define __HAVE_GENERIC_SELECTION 0 #endif #endif /* sys/cdefs.h */
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