1 | /* libc/sys/linux/sys/cdefs.h - Helper macros for K&R vs. ANSI C compat. */ |
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2 | |
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3 | /* Written 2000 by Werner Almesberger */ |
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4 | |
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5 | /*- |
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6 | * Copyright (c) 1991, 1993 |
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7 | * The Regents of the University of California. All rights reserved. |
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8 | * |
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9 | * This code is derived from software contributed to Berkeley by |
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10 | * Berkeley Software Design, Inc. |
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11 | * |
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12 | * Redistribution and use in source and binary forms, with or without |
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13 | * modification, are permitted provided that the following conditions |
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14 | * are met: |
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15 | * 1. Redistributions of source code must retain the above copyright |
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16 | * notice, this list of conditions and the following disclaimer. |
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17 | * 2. Redistributions in binary form must reproduce the above copyright |
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18 | * notice, this list of conditions and the following disclaimer in the |
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19 | * documentation and/or other materials provided with the distribution. |
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20 | * 3. Neither the name of the University nor the names of its contributors |
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21 | * may be used to endorse or promote products derived from this software |
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22 | * without specific prior written permission. |
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23 | * |
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24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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34 | * SUCH DAMAGE. |
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35 | * |
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36 | * @(#)cdefs.h 8.8 (Berkeley) 1/9/95 |
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37 | * $FreeBSD$ |
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38 | */ |
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39 | |
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40 | #ifndef _SYS_CDEFS_H_ |
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41 | #define _SYS_CDEFS_H_ |
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42 | |
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43 | #include <machine/_default_types.h> |
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44 | #include <sys/features.h> |
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45 | #include <stddef.h> |
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46 | |
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47 | #define __PMT(args) args |
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48 | #define __DOTS , ... |
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49 | #define __THROW |
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50 | |
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51 | #ifdef __GNUC__ |
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52 | # define __ASMNAME(cname) __XSTRING (__USER_LABEL_PREFIX__) cname |
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53 | #endif |
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54 | |
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55 | #define __ptr_t void * |
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56 | #define __long_double_t long double |
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57 | |
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58 | #define __attribute_malloc__ |
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59 | #define __attribute_pure__ |
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60 | #define __attribute_format_strfmon__(a,b) |
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61 | #define __flexarr [0] |
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62 | |
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63 | #ifndef __BOUNDED_POINTERS__ |
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64 | # define __bounded /* nothing */ |
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65 | # define __unbounded /* nothing */ |
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66 | # define __ptrvalue /* nothing */ |
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67 | #endif |
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68 | |
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69 | /* |
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70 | * Testing against Clang-specific extensions. |
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71 | */ |
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72 | #ifndef __has_attribute |
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73 | #define __has_attribute(x) 0 |
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74 | #endif |
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75 | #ifndef __has_extension |
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76 | #define __has_extension __has_feature |
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77 | #endif |
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78 | #ifndef __has_feature |
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79 | #define __has_feature(x) 0 |
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80 | #endif |
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81 | #ifndef __has_include |
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82 | #define __has_include(x) 0 |
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83 | #endif |
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84 | #ifndef __has_builtin |
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85 | #define __has_builtin(x) 0 |
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86 | #endif |
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87 | |
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88 | #if defined(__cplusplus) |
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89 | #define __BEGIN_DECLS extern "C" { |
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90 | #define __END_DECLS } |
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91 | #else |
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92 | #define __BEGIN_DECLS |
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93 | #define __END_DECLS |
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94 | #endif |
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95 | |
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96 | /* |
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97 | * This code has been put in place to help reduce the addition of |
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98 | * compiler specific defines in FreeBSD code. It helps to aid in |
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99 | * having a compiler-agnostic source tree. |
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100 | */ |
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101 | |
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102 | #if defined(__GNUC__) || defined(__INTEL_COMPILER) |
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103 | |
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104 | #if __GNUC__ >= 3 || defined(__INTEL_COMPILER) |
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105 | #define __GNUCLIKE_ASM 3 |
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106 | #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS |
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107 | #else |
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108 | #define __GNUCLIKE_ASM 2 |
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109 | #endif |
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110 | #define __GNUCLIKE___TYPEOF 1 |
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111 | #define __GNUCLIKE___OFFSETOF 1 |
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112 | #define __GNUCLIKE___SECTION 1 |
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113 | |
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114 | #ifndef __INTEL_COMPILER |
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115 | #define __GNUCLIKE_CTOR_SECTION_HANDLING 1 |
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116 | #endif |
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117 | |
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118 | #define __GNUCLIKE_BUILTIN_CONSTANT_P 1 |
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119 | #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \ |
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120 | __INTEL_COMPILER < 800 |
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121 | #undef __GNUCLIKE_BUILTIN_CONSTANT_P |
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122 | #endif |
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123 | |
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124 | #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3) |
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125 | #define __GNUCLIKE_BUILTIN_VARARGS 1 |
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126 | #define __GNUCLIKE_BUILTIN_STDARG 1 |
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127 | #define __GNUCLIKE_BUILTIN_VAALIST 1 |
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128 | #endif |
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129 | |
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130 | #if defined(__GNUC__) |
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131 | #define __GNUC_VA_LIST_COMPATIBILITY 1 |
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132 | #endif |
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133 | |
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134 | /* |
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135 | * Compiler memory barriers, specific to gcc and clang. |
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136 | */ |
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137 | #if defined(__GNUC__) |
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138 | #define __compiler_membar() __asm __volatile(" " : : : "memory") |
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139 | #endif |
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140 | |
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141 | #ifndef __INTEL_COMPILER |
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142 | #define __GNUCLIKE_BUILTIN_NEXT_ARG 1 |
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143 | #define __GNUCLIKE_MATH_BUILTIN_RELOPS |
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144 | #endif |
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145 | |
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146 | #define __GNUCLIKE_BUILTIN_MEMCPY 1 |
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147 | |
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148 | /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */ |
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149 | #define __CC_SUPPORTS_INLINE 1 |
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150 | #define __CC_SUPPORTS___INLINE 1 |
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151 | #define __CC_SUPPORTS___INLINE__ 1 |
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152 | |
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153 | #define __CC_SUPPORTS___FUNC__ 1 |
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154 | #define __CC_SUPPORTS_WARNING 1 |
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155 | |
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156 | #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */ |
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157 | |
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158 | #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1 |
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159 | |
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160 | #endif /* __GNUC__ || __INTEL_COMPILER */ |
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161 | |
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162 | /* |
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163 | * The __CONCAT macro is used to concatenate parts of symbol names, e.g. |
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164 | * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo. |
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165 | * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI |
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166 | * mode -- there must be no spaces between its arguments, and for nested |
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167 | * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also |
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168 | * concatenate double-quoted strings produced by the __STRING macro, but |
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169 | * this only works with ANSI C. |
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170 | * |
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171 | * __XSTRING is like __STRING, but it expands any macros in its argument |
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172 | * first. It is only available with ANSI C. |
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173 | */ |
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174 | #if defined(__STDC__) || defined(__cplusplus) |
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175 | #define __P(protos) protos /* full-blown ANSI C */ |
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176 | #define __CONCAT1(x,y) x ## y |
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177 | #define __CONCAT(x,y) __CONCAT1(x,y) |
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178 | #define __STRING(x) #x /* stringify without expanding x */ |
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179 | #define __XSTRING(x) __STRING(x) /* expand x, then stringify */ |
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180 | |
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181 | #define __const const /* define reserved names to standard */ |
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182 | #define __signed signed |
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183 | #define __volatile volatile |
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184 | #if defined(__cplusplus) |
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185 | #define __inline inline /* convert to C++ keyword */ |
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186 | #else |
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187 | #if !(defined(__CC_SUPPORTS___INLINE)) |
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188 | #define __inline /* delete GCC keyword */ |
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189 | #endif /* ! __CC_SUPPORTS___INLINE */ |
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190 | #endif /* !__cplusplus */ |
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191 | |
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192 | #else /* !(__STDC__ || __cplusplus) */ |
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193 | #define __P(protos) () /* traditional C preprocessor */ |
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194 | #define __CONCAT(x,y) x/**/y |
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195 | #define __STRING(x) "x" |
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196 | |
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197 | #if !defined(__CC_SUPPORTS___INLINE) |
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198 | #define __const /* delete pseudo-ANSI C keywords */ |
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199 | #define __inline |
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200 | #define __signed |
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201 | #define __volatile |
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202 | /* |
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203 | * In non-ANSI C environments, new programs will want ANSI-only C keywords |
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204 | * deleted from the program and old programs will want them left alone. |
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205 | * When using a compiler other than gcc, programs using the ANSI C keywords |
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206 | * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS. |
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207 | * When using "gcc -traditional", we assume that this is the intent; if |
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208 | * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone. |
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209 | */ |
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210 | #ifndef NO_ANSI_KEYWORDS |
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211 | #define const /* delete ANSI C keywords */ |
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212 | #define inline |
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213 | #define signed |
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214 | #define volatile |
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215 | #endif /* !NO_ANSI_KEYWORDS */ |
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216 | #endif /* !__CC_SUPPORTS___INLINE */ |
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217 | #endif /* !(__STDC__ || __cplusplus) */ |
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218 | |
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219 | /* |
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220 | * Compiler-dependent macros to help declare dead (non-returning) and |
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221 | * pure (no side effects) functions, and unused variables. They are |
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222 | * null except for versions of gcc that are known to support the features |
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223 | * properly (old versions of gcc-2 supported the dead and pure features |
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224 | * in a different (wrong) way). If we do not provide an implementation |
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225 | * for a given compiler, let the compile fail if it is told to use |
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226 | * a feature that we cannot live without. |
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227 | */ |
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228 | #ifdef lint |
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229 | #define __dead2 |
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230 | #define __pure2 |
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231 | #define __unused |
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232 | #define __packed |
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233 | #define __aligned(x) |
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234 | #define __alloc_align(x) |
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235 | #define __alloc_size(x) |
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236 | #define __section(x) |
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237 | #define __weak_symbol |
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238 | #else |
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239 | #define __weak_symbol __attribute__((__weak__)) |
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240 | #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER) |
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241 | #define __dead2 |
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242 | #define __pure2 |
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243 | #define __unused |
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244 | #endif |
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245 | #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER) |
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246 | #define __dead2 __attribute__((__noreturn__)) |
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247 | #define __pure2 __attribute__((__const__)) |
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248 | #define __unused |
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249 | /* XXX Find out what to do for __packed, __aligned and __section */ |
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250 | #endif |
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251 | #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER) |
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252 | #define __dead2 __attribute__((__noreturn__)) |
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253 | #define __pure2 __attribute__((__const__)) |
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254 | #define __unused __attribute__((__unused__)) |
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255 | #define __used __attribute__((__used__)) |
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256 | #define __packed __attribute__((__packed__)) |
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257 | #define __aligned(x) __attribute__((__aligned__(x))) |
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258 | #define __section(x) __attribute__((__section__(x))) |
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259 | #endif |
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260 | #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__) |
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261 | #define __alloc_size(x) __attribute__((__alloc_size__(x))) |
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262 | #else |
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263 | #define __alloc_size(x) |
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264 | #endif |
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265 | #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__) |
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266 | #define __alloc_align(x) __attribute__((__alloc_align__(x))) |
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267 | #else |
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268 | #define __alloc_align(x) |
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269 | #endif |
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270 | #endif /* lint */ |
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271 | |
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272 | #if !__GNUC_PREREQ__(2, 95) |
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273 | #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b) |
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274 | #endif |
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275 | |
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276 | /* |
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277 | * Keywords added in C11. |
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278 | */ |
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279 | |
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280 | #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint) |
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281 | |
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282 | #if !__has_extension(c_alignas) |
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283 | #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ |
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284 | __has_extension(cxx_alignas) |
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285 | #define _Alignas(x) alignas(x) |
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286 | #else |
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287 | /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */ |
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288 | #define _Alignas(x) __aligned(x) |
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289 | #endif |
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290 | #endif |
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291 | |
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292 | #if defined(__cplusplus) && __cplusplus >= 201103L |
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293 | #define _Alignof(x) alignof(x) |
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294 | #else |
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295 | #define _Alignof(x) __alignof(x) |
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296 | #endif |
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297 | |
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298 | #if !defined(__cplusplus) && !__has_extension(c_atomic) && \ |
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299 | !__has_extension(cxx_atomic) |
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300 | /* |
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301 | * No native support for _Atomic(). Place object in structure to prevent |
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302 | * most forms of direct non-atomic access. |
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303 | */ |
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304 | #define _Atomic(T) struct { T volatile __val; } |
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305 | #endif |
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306 | |
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307 | #if defined(__cplusplus) && __cplusplus >= 201103L |
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308 | #define _Noreturn [[noreturn]] |
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309 | #else |
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310 | #define _Noreturn __dead2 |
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311 | #endif |
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312 | |
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313 | #if !__has_extension(c_static_assert) |
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314 | #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ |
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315 | __has_extension(cxx_static_assert) |
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316 | #define _Static_assert(x, y) static_assert(x, y) |
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317 | #elif __GNUC_PREREQ__(4,6) |
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318 | /* Nothing, gcc 4.6 and higher has _Static_assert built-in */ |
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319 | #elif defined(__COUNTER__) |
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320 | #define _Static_assert(x, y) __Static_assert(x, __COUNTER__) |
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321 | #define __Static_assert(x, y) ___Static_assert(x, y) |
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322 | #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \ |
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323 | __unused |
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324 | #else |
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325 | #define _Static_assert(x, y) struct __hack |
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326 | #endif |
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327 | #endif |
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328 | |
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329 | #if !__has_extension(c_thread_local) |
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330 | /* |
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331 | * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode |
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332 | * without actually supporting the thread_local keyword. Don't check for |
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333 | * the presence of C++11 when defining _Thread_local. |
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334 | */ |
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335 | #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \ |
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336 | __has_extension(cxx_thread_local) |
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337 | #define _Thread_local thread_local |
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338 | #else |
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339 | #define _Thread_local __thread |
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340 | #endif |
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341 | #endif |
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342 | |
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343 | #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */ |
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344 | |
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345 | /* |
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346 | * Emulation of C11 _Generic(). Unlike the previously defined C11 |
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347 | * keywords, it is not possible to implement this using exactly the same |
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348 | * syntax. Therefore implement something similar under the name |
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349 | * __generic(). Unlike _Generic(), this macro can only distinguish |
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350 | * between a single type, so it requires nested invocations to |
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351 | * distinguish multiple cases. |
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352 | */ |
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353 | |
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354 | #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \ |
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355 | __has_extension(c_generic_selections) |
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356 | #define __generic(expr, t, yes, no) \ |
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357 | _Generic(expr, t: yes, default: no) |
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358 | #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus) |
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359 | #define __generic(expr, t, yes, no) \ |
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360 | __builtin_choose_expr( \ |
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361 | __builtin_types_compatible_p(__typeof(expr), t), yes, no) |
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362 | #endif |
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363 | |
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364 | /* |
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365 | * C99 Static array indices in function parameter declarations. Syntax such as: |
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366 | * void bar(int myArray[static 10]); |
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367 | * is allowed in C99 but not in C++. Define __min_size appropriately so |
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368 | * headers using it can be compiled in either language. Use like this: |
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369 | * void bar(int myArray[__min_size(10)]); |
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370 | */ |
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371 | #if !defined(__cplusplus) && \ |
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372 | (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \ |
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373 | (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901)) |
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374 | #define __min_size(x) static (x) |
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375 | #else |
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376 | #define __min_size(x) (x) |
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377 | #endif |
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378 | |
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379 | #if __GNUC_PREREQ__(2, 96) |
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380 | #define __malloc_like __attribute__((__malloc__)) |
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381 | #define __pure __attribute__((__pure__)) |
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382 | #else |
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383 | #define __malloc_like |
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384 | #define __pure |
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385 | #endif |
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386 | |
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387 | #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800) |
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388 | #define __always_inline __inline__ __attribute__((__always_inline__)) |
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389 | #else |
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390 | #define __always_inline |
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391 | #endif |
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392 | |
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393 | #if __GNUC_PREREQ__(3, 1) |
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394 | #define __noinline __attribute__ ((__noinline__)) |
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395 | #else |
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396 | #define __noinline |
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397 | #endif |
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398 | |
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399 | #if __GNUC_PREREQ__(3, 3) |
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400 | #define __nonnull(x) __attribute__((__nonnull__ x)) |
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401 | #define __nonnull_all __attribute__((__nonnull__)) |
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402 | #else |
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403 | #define __nonnull(x) |
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404 | #define __nonnull_all |
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405 | #endif |
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406 | |
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407 | #if __GNUC_PREREQ__(3, 4) |
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408 | #define __fastcall __attribute__((__fastcall__)) |
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409 | #define __result_use_check __attribute__((__warn_unused_result__)) |
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410 | #else |
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411 | #define __fastcall |
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412 | #define __result_use_check |
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413 | #endif |
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414 | |
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415 | #if __GNUC_PREREQ__(4, 1) |
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416 | #define __returns_twice __attribute__((__returns_twice__)) |
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417 | #else |
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418 | #define __returns_twice |
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419 | #endif |
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420 | |
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421 | #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable) |
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422 | #define __unreachable() __builtin_unreachable() |
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423 | #else |
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424 | #define __unreachable() ((void)0) |
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425 | #endif |
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426 | |
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427 | /* XXX: should use `#if __STDC_VERSION__ < 199901'. */ |
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428 | #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER) |
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429 | #define __func__ NULL |
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430 | #endif |
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431 | |
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432 | /* |
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433 | * GCC 2.95 provides `__restrict' as an extension to C90 to support the |
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434 | * C99-specific `restrict' type qualifier. We happen to use `__restrict' as |
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435 | * a way to define the `restrict' type qualifier without disturbing older |
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436 | * software that is unaware of C99 keywords. |
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437 | */ |
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438 | #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95) |
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439 | #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint) |
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440 | #define __restrict |
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441 | #else |
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442 | #define __restrict restrict |
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443 | #endif |
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444 | #endif |
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445 | |
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446 | /* |
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447 | * GNU C version 2.96 adds explicit branch prediction so that |
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448 | * the CPU back-end can hint the processor and also so that |
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449 | * code blocks can be reordered such that the predicted path |
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450 | * sees a more linear flow, thus improving cache behavior, etc. |
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451 | * |
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452 | * The following two macros provide us with a way to utilize this |
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453 | * compiler feature. Use __predict_true() if you expect the expression |
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454 | * to evaluate to true, and __predict_false() if you expect the |
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455 | * expression to evaluate to false. |
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456 | * |
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457 | * A few notes about usage: |
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458 | * |
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459 | * * Generally, __predict_false() error condition checks (unless |
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460 | * you have some _strong_ reason to do otherwise, in which case |
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461 | * document it), and/or __predict_true() `no-error' condition |
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462 | * checks, assuming you want to optimize for the no-error case. |
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463 | * |
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464 | * * Other than that, if you don't know the likelihood of a test |
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465 | * succeeding from empirical or other `hard' evidence, don't |
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466 | * make predictions. |
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467 | * |
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468 | * * These are meant to be used in places that are run `a lot'. |
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469 | * It is wasteful to make predictions in code that is run |
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470 | * seldomly (e.g. at subsystem initialization time) as the |
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471 | * basic block reordering that this affects can often generate |
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472 | * larger code. |
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473 | */ |
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474 | #if __GNUC_PREREQ__(2, 96) |
---|
475 | #define __predict_true(exp) __builtin_expect((exp), 1) |
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476 | #define __predict_false(exp) __builtin_expect((exp), 0) |
---|
477 | #else |
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478 | #define __predict_true(exp) (exp) |
---|
479 | #define __predict_false(exp) (exp) |
---|
480 | #endif |
---|
481 | |
---|
482 | #if __GNUC_PREREQ__(4, 0) |
---|
483 | #define __null_sentinel __attribute__((__sentinel__)) |
---|
484 | #define __exported __attribute__((__visibility__("default"))) |
---|
485 | /* Only default visibility is supported on PE/COFF targets. */ |
---|
486 | #ifndef __CYGWIN__ |
---|
487 | #define __hidden __attribute__((__visibility__("hidden"))) |
---|
488 | #else |
---|
489 | #define __hidden |
---|
490 | #endif |
---|
491 | #else |
---|
492 | #define __null_sentinel |
---|
493 | #define __exported |
---|
494 | #define __hidden |
---|
495 | #endif |
---|
496 | |
---|
497 | #define __offsetof(type, field) offsetof(type, field) |
---|
498 | #define __rangeof(type, start, end) \ |
---|
499 | (__offsetof(type, end) - __offsetof(type, start)) |
---|
500 | |
---|
501 | /* |
---|
502 | * Given the pointer x to the member m of the struct s, return |
---|
503 | * a pointer to the containing structure. When using GCC, we first |
---|
504 | * assign pointer x to a local variable, to check that its type is |
---|
505 | * compatible with member m. |
---|
506 | */ |
---|
507 | #if __GNUC_PREREQ__(3, 1) |
---|
508 | #define __containerof(x, s, m) ({ \ |
---|
509 | const volatile __typeof(((s *)0)->m) *__x = (x); \ |
---|
510 | __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\ |
---|
511 | }) |
---|
512 | #else |
---|
513 | #define __containerof(x, s, m) \ |
---|
514 | __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m)) |
---|
515 | #endif |
---|
516 | |
---|
517 | /* |
---|
518 | * Compiler-dependent macros to declare that functions take printf-like |
---|
519 | * or scanf-like arguments. They are null except for versions of gcc |
---|
520 | * that are known to support the features properly (old versions of gcc-2 |
---|
521 | * didn't permit keeping the keywords out of the application namespace). |
---|
522 | */ |
---|
523 | #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER) |
---|
524 | #define __printflike(fmtarg, firstvararg) |
---|
525 | #define __scanflike(fmtarg, firstvararg) |
---|
526 | #define __format_arg(fmtarg) |
---|
527 | #define __strfmonlike(fmtarg, firstvararg) |
---|
528 | #define __strftimelike(fmtarg, firstvararg) |
---|
529 | #else |
---|
530 | #define __printflike(fmtarg, firstvararg) \ |
---|
531 | __attribute__((__format__ (__printf__, fmtarg, firstvararg))) |
---|
532 | #define __scanflike(fmtarg, firstvararg) \ |
---|
533 | __attribute__((__format__ (__scanf__, fmtarg, firstvararg))) |
---|
534 | #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg))) |
---|
535 | #define __strfmonlike(fmtarg, firstvararg) \ |
---|
536 | __attribute__((__format__ (__strfmon__, fmtarg, firstvararg))) |
---|
537 | #define __strftimelike(fmtarg, firstvararg) \ |
---|
538 | __attribute__((__format__ (__strftime__, fmtarg, firstvararg))) |
---|
539 | #endif |
---|
540 | |
---|
541 | /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */ |
---|
542 | #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \ |
---|
543 | defined(__GNUC__) && !defined(__INTEL_COMPILER) |
---|
544 | #define __printf0like(fmtarg, firstvararg) \ |
---|
545 | __attribute__((__format__ (__printf0__, fmtarg, firstvararg))) |
---|
546 | #else |
---|
547 | #define __printf0like(fmtarg, firstvararg) |
---|
548 | #endif |
---|
549 | |
---|
550 | #if defined(__GNUC__) || defined(__INTEL_COMPILER) |
---|
551 | #ifndef __INTEL_COMPILER |
---|
552 | #define __strong_reference(sym,aliassym) \ |
---|
553 | extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym))) |
---|
554 | #endif |
---|
555 | #ifdef __ELF__ |
---|
556 | #ifdef __STDC__ |
---|
557 | #define __weak_reference(sym,alias) \ |
---|
558 | __asm__(".weak " #alias); \ |
---|
559 | __asm__(".equ " #alias ", " #sym) |
---|
560 | #define __warn_references(sym,msg) \ |
---|
561 | __asm__(".section .gnu.warning." #sym); \ |
---|
562 | __asm__(".asciz \"" msg "\""); \ |
---|
563 | __asm__(".previous") |
---|
564 | #define __sym_compat(sym,impl,verid) \ |
---|
565 | __asm__(".symver " #impl ", " #sym "@" #verid) |
---|
566 | #define __sym_default(sym,impl,verid) \ |
---|
567 | __asm__(".symver " #impl ", " #sym "@@" #verid) |
---|
568 | #else |
---|
569 | #define __weak_reference(sym,alias) \ |
---|
570 | __asm__(".weak alias"); \ |
---|
571 | __asm__(".equ alias, sym") |
---|
572 | #define __warn_references(sym,msg) \ |
---|
573 | __asm__(".section .gnu.warning.sym"); \ |
---|
574 | __asm__(".asciz \"msg\""); \ |
---|
575 | __asm__(".previous") |
---|
576 | #define __sym_compat(sym,impl,verid) \ |
---|
577 | __asm__(".symver impl, sym@verid") |
---|
578 | #define __sym_default(impl,sym,verid) \ |
---|
579 | __asm__(".symver impl, sym@@verid") |
---|
580 | #endif /* __STDC__ */ |
---|
581 | #else /* !__ELF__ */ |
---|
582 | #ifdef __STDC__ |
---|
583 | #define __weak_reference(sym,alias) \ |
---|
584 | __asm__(".stabs \"_" #alias "\",11,0,0,0"); \ |
---|
585 | __asm__(".stabs \"_" #sym "\",1,0,0,0") |
---|
586 | #define __warn_references(sym,msg) \ |
---|
587 | __asm__(".stabs \"" msg "\",30,0,0,0"); \ |
---|
588 | __asm__(".stabs \"_" #sym "\",1,0,0,0") |
---|
589 | #else |
---|
590 | #define __weak_reference(sym,alias) \ |
---|
591 | __asm__(".stabs \"_/**/alias\",11,0,0,0"); \ |
---|
592 | __asm__(".stabs \"_/**/sym\",1,0,0,0") |
---|
593 | #define __warn_references(sym,msg) \ |
---|
594 | __asm__(".stabs msg,30,0,0,0"); \ |
---|
595 | __asm__(".stabs \"_/**/sym\",1,0,0,0") |
---|
596 | #endif /* __STDC__ */ |
---|
597 | #endif /* __ELF__ */ |
---|
598 | #endif /* __GNUC__ || __INTEL_COMPILER */ |
---|
599 | |
---|
600 | #ifndef __FBSDID |
---|
601 | #define __FBSDID(s) struct __hack |
---|
602 | #endif |
---|
603 | |
---|
604 | #ifndef __RCSID |
---|
605 | #define __RCSID(s) struct __hack |
---|
606 | #endif |
---|
607 | |
---|
608 | #ifndef __RCSID_SOURCE |
---|
609 | #define __RCSID_SOURCE(s) struct __hack |
---|
610 | #endif |
---|
611 | |
---|
612 | #ifndef __SCCSID |
---|
613 | #define __SCCSID(s) struct __hack |
---|
614 | #endif |
---|
615 | |
---|
616 | #ifndef __COPYRIGHT |
---|
617 | #define __COPYRIGHT(s) struct __hack |
---|
618 | #endif |
---|
619 | |
---|
620 | #ifndef __DECONST |
---|
621 | #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var)) |
---|
622 | #endif |
---|
623 | |
---|
624 | #ifndef __DEVOLATILE |
---|
625 | #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var)) |
---|
626 | #endif |
---|
627 | |
---|
628 | #ifndef __DEQUALIFY |
---|
629 | #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var)) |
---|
630 | #endif |
---|
631 | |
---|
632 | /* |
---|
633 | * Nullability qualifiers: currently only supported by Clang. |
---|
634 | */ |
---|
635 | #if !(defined(__clang__) && __has_feature(nullability)) |
---|
636 | #define _Nonnull |
---|
637 | #define _Nullable |
---|
638 | #define _Null_unspecified |
---|
639 | #define __NULLABILITY_PRAGMA_PUSH |
---|
640 | #define __NULLABILITY_PRAGMA_POP |
---|
641 | #else |
---|
642 | #define __NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push") \ |
---|
643 | _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"") |
---|
644 | #define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop") |
---|
645 | #endif |
---|
646 | |
---|
647 | /* |
---|
648 | * Type Safety Checking |
---|
649 | * |
---|
650 | * Clang provides additional attributes to enable checking type safety |
---|
651 | * properties that cannot be enforced by the C type system. |
---|
652 | */ |
---|
653 | |
---|
654 | #if __has_attribute(__argument_with_type_tag__) && \ |
---|
655 | __has_attribute(__type_tag_for_datatype__) && !defined(lint) |
---|
656 | #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \ |
---|
657 | __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx))) |
---|
658 | #define __datatype_type_tag(kind, type) \ |
---|
659 | __attribute__((__type_tag_for_datatype__(kind, type))) |
---|
660 | #else |
---|
661 | #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) |
---|
662 | #define __datatype_type_tag(kind, type) |
---|
663 | #endif |
---|
664 | |
---|
665 | /* |
---|
666 | * Lock annotations. |
---|
667 | * |
---|
668 | * Clang provides support for doing basic thread-safety tests at |
---|
669 | * compile-time, by marking which locks will/should be held when |
---|
670 | * entering/leaving a functions. |
---|
671 | * |
---|
672 | * Furthermore, it is also possible to annotate variables and structure |
---|
673 | * members to enforce that they are only accessed when certain locks are |
---|
674 | * held. |
---|
675 | */ |
---|
676 | |
---|
677 | #if __has_extension(c_thread_safety_attributes) |
---|
678 | #define __lock_annotate(x) __attribute__((x)) |
---|
679 | #else |
---|
680 | #define __lock_annotate(x) |
---|
681 | #endif |
---|
682 | |
---|
683 | /* Structure implements a lock. */ |
---|
684 | /* FIXME: Use __lockable__, etc. to avoid colliding with user namespace macros, |
---|
685 | * once clang is fixed: https://bugs.llvm.org/show_bug.cgi?id=34319 */ |
---|
686 | #define __lockable __lock_annotate(lockable) |
---|
687 | |
---|
688 | /* Function acquires an exclusive or shared lock. */ |
---|
689 | #define __locks_exclusive(...) \ |
---|
690 | __lock_annotate(exclusive_lock_function(__VA_ARGS__)) |
---|
691 | #define __locks_shared(...) \ |
---|
692 | __lock_annotate(shared_lock_function(__VA_ARGS__)) |
---|
693 | |
---|
694 | /* Function attempts to acquire an exclusive or shared lock. */ |
---|
695 | #define __trylocks_exclusive(...) \ |
---|
696 | __lock_annotate(exclusive_trylock_function(__VA_ARGS__)) |
---|
697 | #define __trylocks_shared(...) \ |
---|
698 | __lock_annotate(shared_trylock_function(__VA_ARGS__)) |
---|
699 | |
---|
700 | /* Function releases a lock. */ |
---|
701 | #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__)) |
---|
702 | |
---|
703 | /* Function asserts that an exclusive or shared lock is held. */ |
---|
704 | #define __asserts_exclusive(...) \ |
---|
705 | __lock_annotate(assert_exclusive_lock(__VA_ARGS__)) |
---|
706 | #define __asserts_shared(...) \ |
---|
707 | __lock_annotate(assert_shared_lock(__VA_ARGS__)) |
---|
708 | |
---|
709 | /* Function requires that an exclusive or shared lock is or is not held. */ |
---|
710 | #define __requires_exclusive(...) \ |
---|
711 | __lock_annotate(exclusive_locks_required(__VA_ARGS__)) |
---|
712 | #define __requires_shared(...) \ |
---|
713 | __lock_annotate(shared_locks_required(__VA_ARGS__)) |
---|
714 | #define __requires_unlocked(...) \ |
---|
715 | __lock_annotate(locks_excluded(__VA_ARGS__)) |
---|
716 | |
---|
717 | /* Function should not be analyzed. */ |
---|
718 | #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis) |
---|
719 | |
---|
720 | /* Guard variables and structure members by lock. */ |
---|
721 | #define __guarded_by(x) __lock_annotate(guarded_by(x)) |
---|
722 | #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x)) |
---|
723 | |
---|
724 | #endif /* !_SYS_CDEFS_H_ */ |
---|