include/libc-symbols.h

   1 /* Support macros for making weak and strong aliases for symbols,
   2    and for using symbol sets and linker warnings with GNU ld.
   3    Copyright (C) 1995-2012 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _LIBC_SYMBOLS_H
  21 #define _LIBC_SYMBOLS_H 1
  22
  23 /* This file's macros are included implicitly in the compilation of every
  24    file in the C library by -imacros.
  25
  26    We include config.h which is generated by configure.
  27    It should define for us the following symbols:
  28
  29    * HAVE_ASM_SET_DIRECTIVE if we have `.set B, A' instead of `A = B'.
  30    * HAVE_ASM_WEAK_DIRECTIVE if we have weak symbols using `.weak'.
  31    * HAVE_ASM_WEAKEXT_DIRECTIVE if we have weak symbols using `.weakext'.
  32
  33    */
  34
  35 /* This is defined for the compilation of all C library code.  features.h
  36    tests this to avoid inclusion of stubs.h while compiling the library,
  37    before stubs.h has been generated.  Some library code that is shared
  38    with other packages also tests this symbol to see if it is being
  39    compiled as part of the C library.  We must define this before including
  40    config.h, because it makes some definitions conditional on whether libc
  41    itself is being compiled, or just some generator program.  */
  42 #define _LIBC   1
  43
  44 /* Enable declarations of GNU extensions, since we are compiling them.  */
  45 #define _GNU_SOURCE     1
  46 /* And we also need the data for the reentrant functions.  */
  47 #define _REENTRANT      1
  48
  49 #include <config.h>
  50
  51 /* The symbols in all the user (non-_) macros are C symbols.  */
  52
  53 #if !defined HAVE_ASM_WEAK_DIRECTIVE && !defined HAVE_ASM_WEAKEXT_DIRECTIVE
  54 # error "weak symbol support needed"
  55 #endif
  56
  57 #ifndef __SYMBOL_PREFIX
  58 # define __SYMBOL_PREFIX
  59 #endif
  60
  61 #ifndef C_SYMBOL_NAME
  62 # define C_SYMBOL_NAME(name) name
  63 #endif
  64
  65 #ifndef ASM_LINE_SEP
  66 # define ASM_LINE_SEP ;
  67 #endif
  68
  69 #ifdef HAVE_ASM_GLOBAL_DOT_NAME
  70 # ifndef C_SYMBOL_DOT_NAME
  71 #  if defined __GNUC__ && defined __GNUC_MINOR__ \
  72       && (__GNUC__ << 16) + __GNUC_MINOR__ >= (3 << 16) + 1
  73 #   define C_SYMBOL_DOT_NAME(name) .name
  74 #  else
  75 #   define C_SYMBOL_DOT_NAME(name) .##name
  76 #  endif
  77 # endif
  78 #endif
  79
  80 #ifndef __ASSEMBLER__
  81 /* GCC understands weak symbols and aliases; use its interface where
  82    possible, instead of embedded assembly language.  */
  83
  84 /* Define ALIASNAME as a strong alias for NAME.  */
  85 # define strong_alias(name, aliasname) _strong_alias(name, aliasname)
  86 # define _strong_alias(name, aliasname) \
  87   extern __typeof (name) aliasname __attribute__ ((alias (#name)));
  88
  89 /* This comes between the return type and function name in
  90    a function definition to make that definition weak.  */
  91 # define weak_function __attribute__ ((weak))
  92 # define weak_const_function __attribute__ ((weak, __const__))
  93
  94 /* Define ALIASNAME as a weak alias for NAME.
  95    If weak aliases are not available, this defines a strong alias.  */
  96 # define weak_alias(name, aliasname) _weak_alias (name, aliasname)
  97 # define _weak_alias(name, aliasname) \
  98   extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
  99
 100 /* Same as WEAK_ALIAS, but mark symbol as hidden.  */
 101 # define weak_hidden_alias(name, aliasname) \
 102   _weak_hidden_alias (name, aliasname)
 103 # define _weak_hidden_alias(name, aliasname) \
 104   extern __typeof (name) aliasname \
 105     __attribute__ ((weak, alias (#name), __visibility__ ("hidden")));
 106
 107 /* Declare SYMBOL as weak undefined symbol (resolved to 0 if not defined).  */
 108 # define weak_extern(symbol) _weak_extern (weak symbol)
 109 # define _weak_extern(expr) _Pragma (#expr)
 110
 111
 112 #else /* __ASSEMBLER__ */
 113
 114 # ifdef HAVE_ASM_SET_DIRECTIVE
 115 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 116 #   define strong_alias(original, alias)                                \
 117   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 118   .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) ASM_LINE_SEP      \
 119   .globl C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP         \
 120   .set C_SYMBOL_DOT_NAME (alias),C_SYMBOL_DOT_NAME (original)
 121 #   define strong_data_alias(original, alias)                           \
 122   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 123   .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original)
 124 #  else
 125 #   define strong_alias(original, alias)                                \
 126   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 127   .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original)
 128 #   define strong_data_alias(original, alias) strong_alias(original, alias)
 129 #  endif
 130 # else
 131 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 132 #   define strong_alias(original, alias)                                \
 133   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 134   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP         \
 135   .globl C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP         \
 136   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 137 #   define strong_data_alias(original, alias)                           \
 138   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 139   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 140 #  else
 141 #   define strong_alias(original, alias)                                \
 142   .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP             \
 143   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 144 #   define strong_data_alias(original, alias) strong_alias(original, alias)
 145 #  endif
 146 # endif
 147
 148 # ifdef HAVE_ASM_WEAKEXT_DIRECTIVE
 149 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 150 #   define weak_alias(original, alias)                                  \
 151   .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) ASM_LINE_SEP \
 152   .weakext C_SYMBOL_DOT_NAME (alias), C_SYMBOL_DOT_NAME (original)
 153 #  else
 154 #   define weak_alias(original, alias)                                  \
 155   .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original)
 156 #  endif
 157 #  define weak_extern(symbol)                                           \
 158   .weakext C_SYMBOL_NAME (symbol)
 159
 160 # else /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
 161
 162 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 163 #   define weak_alias(original, alias)                                  \
 164   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP                              \
 165   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP         \
 166   .weak C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP                          \
 167   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 168 #  else
 169 #   define weak_alias(original, alias)                                  \
 170   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP                              \
 171   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 172 #  endif
 173
 174 #  define weak_extern(symbol)                                           \
 175   .weak C_SYMBOL_NAME (symbol)
 176
 177 # endif /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
 178
 179 #endif /* __ASSEMBLER__ */
 180
 181 /* On some platforms we can make internal function calls (i.e., calls of
 182    functions not exported) a bit faster by using a different calling
 183    convention.  */
 184 #ifndef internal_function
 185 # define internal_function      /* empty */
 186 #endif
 187
 188 /* Determine the return address.  */
 189 #define RETURN_ADDRESS(nr) \
 190   __builtin_extract_return_addr (__builtin_return_address (nr))
 191
 192 /* When a reference to SYMBOL is encountered, the linker will emit a
 193    warning message MSG.  */
 194 /* We want the .gnu.warning.SYMBOL section to be unallocated.  */
 195 #ifdef HAVE_ASM_PREVIOUS_DIRECTIVE
 196 # define __make_section_unallocated(section_string)     \
 197   asm (".section " section_string "\n\t.previous");
 198 #elif defined HAVE_ASM_POPSECTION_DIRECTIVE
 199 # define __make_section_unallocated(section_string)     \
 200   asm (".pushsection " section_string "\n\t.popsection");
 201 #else
 202 # define __make_section_unallocated(section_string)
 203 #endif
 204
 205 /* Tacking on "\n\t#" to the section name makes gcc put it's bogus
 206    section attributes on what looks like a comment to the assembler.  */
 207 #ifdef HAVE_SECTION_QUOTES
 208 # define __sec_comment "\"\n\t#\""
 209 #else
 210 # define __sec_comment "\n\t#"
 211 #endif
 212 #define link_warning(symbol, msg) \
 213   __make_section_unallocated (".gnu.warning." #symbol) \
 214   static const char __evoke_link_warning_##symbol[]     \
 215     __attribute__ ((used, section (".gnu.warning." #symbol __sec_comment))) \
 216     = msg;
 217 #define libc_freeres_ptr(decl) \
 218   __make_section_unallocated ("__libc_freeres_ptrs, \"aw\", %nobits") \
 219   decl __attribute__ ((section ("__libc_freeres_ptrs" __sec_comment)))
 220 #define __libc_freeres_fn_section \
 221   __attribute__ ((section ("__libc_freeres_fn")))
 222
 223 #define libc_freeres_fn(name)   \
 224   static void name (void) __attribute_used__ __libc_freeres_fn_section; \
 225   text_set_element (__libc_subfreeres, name);                           \
 226   static void name (void)
 227
 228 /* A canned warning for sysdeps/stub functions.  */
 229 #define stub_warning(name) \
 230   __make_section_unallocated (".gnu.glibc-stub." #name) \
 231   link_warning (name, \
 232                 "warning: " #name " is not implemented and will always fail")
 233
 234 /* Warning for linking functions calling dlopen into static binaries.  */
 235 #ifdef SHARED
 236 #define static_link_warning(name)
 237 #else
 238 #define static_link_warning(name) static_link_warning1(name)
 239 #define static_link_warning1(name) \
 240   link_warning(name, "Using '" #name "' in statically linked applications \
 241 requires at runtime the shared libraries from the glibc version used \
 242 for linking")
 243 #endif
 244
 245 /* Declare SYMBOL to be TYPE (`function' or `object') of SIZE bytes
 246    alias to ORIGINAL, when the assembler supports such declarations
 247    (such as in ELF).
 248    This is only necessary when defining something in assembly, or playing
 249    funny alias games where the size should be other than what the compiler
 250    thinks it is.  */
 251 #define declare_symbol_alias(symbol, original, type, size) \
 252   declare_symbol_alias_1 (symbol, original, type, size)
 253 #ifdef __ASSEMBLER__
 254 # define declare_symbol_alias_1(symbol, original, type, size) \
 255    strong_alias (original, symbol); \
 256    .type C_SYMBOL_NAME (symbol), %##type; \
 257    .size C_SYMBOL_NAME (symbol), size
 258 #else /* Not __ASSEMBLER__.  */
 259 # define declare_symbol_alias_1(symbol, original, type, size) \
 260    asm (".globl " __SYMBOL_PREFIX #symbol \
 261         "\n\t" declare_symbol_alias_1_alias (symbol, original) \
 262         "\n\t.type " __SYMBOL_PREFIX #symbol ", " \
 263         "%" #type \
 264         "\n\t.size " __SYMBOL_PREFIX #symbol ", " #size);
 265 # ifdef HAVE_ASM_SET_DIRECTIVE
 266 #  define declare_symbol_alias_1_alias(symbol, original) \
 267      ".set " __SYMBOL_PREFIX #symbol ", " __SYMBOL_PREFIX #original
 268 # else
 269 #  define declare_symbol_alias_1_alias(symbol, original) \
 270      __SYMBOL_PREFIX #symbol " = " __SYMBOL_PREFIX #original
 271 # endif /* HAVE_ASM_SET_DIRECTIVE */
 272 #endif /* __ASSEMBLER__ */
 273
 274
 275 /*
 276 \f
 277 */
 278
 279 /* Symbol set support macros.  */
 280
 281 /* Make SYMBOL, which is in the text segment, an element of SET.  */
 282 #define text_set_element(set, symbol)   _elf_set_element(set, symbol)
 283 /* Make SYMBOL, which is in the data segment, an element of SET.  */
 284 #define data_set_element(set, symbol)   _elf_set_element(set, symbol)
 285 /* Make SYMBOL, which is in the bss segment, an element of SET.  */
 286 #define bss_set_element(set, symbol)    _elf_set_element(set, symbol)
 287
 288 /* These are all done the same way in ELF.
 289    There is a new section created for each set.  */
 290 #ifdef SHARED
 291 /* When building a shared library, make the set section writable,
 292    because it will need to be relocated at run time anyway.  */
 293 # define _elf_set_element(set, symbol) \
 294   static const void *__elf_set_##set##_element_##symbol##__ \
 295     __attribute__ ((used, section (#set))) = &(symbol)
 296 #else
 297 # define _elf_set_element(set, symbol) \
 298   static const void *const __elf_set_##set##_element_##symbol##__ \
 299     __attribute__ ((used, section (#set))) = &(symbol)
 300 #endif
 301
 302 /* Define SET as a symbol set.  This may be required (it is in a.out) to
 303    be able to use the set's contents.  */
 304 #define symbol_set_define(set)  symbol_set_declare(set)
 305
 306 /* Declare SET for use in this module, if defined in another module.
 307    In a shared library, this is always local to that shared object.
 308    For static linking, the set might be wholly absent and so we use
 309    weak references.  */
 310 #define symbol_set_declare(set) \
 311   extern char const __start_##set[] __symbol_set_attribute; \
 312   extern char const __stop_##set[] __symbol_set_attribute;
 313 #ifdef SHARED
 314 # define __symbol_set_attribute attribute_hidden
 315 #else
 316 # define __symbol_set_attribute __attribute__ ((weak))
 317 #endif
 318
 319 /* Return a pointer (void *const *) to the first element of SET.  */
 320 #define symbol_set_first_element(set)   ((void *const *) (&__start_##set))
 321
 322 /* Return true iff PTR (a void *const *) has been incremented
 323    past the last element in SET.  */
 324 #define symbol_set_end_p(set, ptr) ((ptr) >= (void *const *) &__stop_##set)
 325
 326 #if DO_VERSIONING
 327 # define symbol_version(real, name, version) \
 328      _symbol_version(real, name, version)
 329 # define default_symbol_version(real, name, version) \
 330      _default_symbol_version(real, name, version)
 331 # ifdef __ASSEMBLER__
 332 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 333 #   define _symbol_version(real, name, version) \
 334      .symver real, name##@##version ASM_LINE_SEP                        \
 335      .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##version)
 336 #   define _default_symbol_version(real, name, version) \
 337      .symver real, name##@##@##version ASM_LINE_SEP                     \
 338      .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##@##version)
 339 #  else
 340 #   define _symbol_version(real, name, version) \
 341      .symver real, name##@##version
 342 #   define _default_symbol_version(real, name, version) \
 343      .symver real, name##@##@##version
 344 #  endif
 345 # else
 346 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 347 #   define _symbol_version(real, name, version) \
 348      __asm__ (".symver " #real "," #name "@" #version "\n\t"    \
 349               ".symver ." #real ",." #name "@" #version)
 350 #   define _default_symbol_version(real, name, version) \
 351      __asm__ (".symver " #real "," #name "@@" #version "\n\t"   \
 352               ".symver ." #real ",." #name "@@" #version)
 353 #  else
 354 #   define _symbol_version(real, name, version) \
 355      __asm__ (".symver " #real "," #name "@" #version)
 356 #   define _default_symbol_version(real, name, version) \
 357      __asm__ (".symver " #real "," #name "@@" #version)
 358 #  endif
 359 # endif
 360 #else
 361 # define symbol_version(real, name, version)
 362 # define default_symbol_version(real, name, version) \
 363   strong_alias(real, name)
 364 #endif
 365
 366 #if defined SHARED || defined LIBC_NONSHARED
 367 # define attribute_hidden __attribute__ ((visibility ("hidden")))
 368 #else
 369 # define attribute_hidden
 370 #endif
 371
 372 #define attribute_tls_model_ie __attribute__ ((tls_model ("initial-exec")))
 373
 374 #define attribute_relro __attribute__ ((section (".data.rel.ro")))
 375
 376 /* Handling on non-exported internal names.  We have to do this only
 377    for shared code.  */
 378 #ifdef SHARED
 379 # define INTUSE(name) name##_internal
 380 # define INTDEF(name) strong_alias (name, name##_internal)
 381 # define INTVARDEF(name) \
 382   _INTVARDEF (name, name##_internal)
 383 # define _INTVARDEF(name, aliasname) \
 384   extern __typeof (name) aliasname __attribute__ ((alias (#name), \
 385                                                    visibility ("hidden")));
 386 # define INTDEF2(name, newname) strong_alias (name, newname##_internal)
 387 # define INTVARDEF2(name, newname) _INTVARDEF (name, newname##_internal)
 388 #else
 389 # define INTUSE(name) name
 390 # define INTDEF(name)
 391 # define INTVARDEF(name)
 392 # define INTDEF2(name, newname)
 393 # define INTVARDEF2(name, newname)
 394 #endif
 395
 396 /* The following macros are used for PLT bypassing within libc.so
 397    (and if needed other libraries similarly).
 398    First of all, you need to have the function prototyped somewhere,
 399    say in foo/foo.h:
 400
 401    int foo (int __bar);
 402
 403    If calls to foo within libc.so should always go to foo defined in libc.so,
 404    then in include/foo.h you add:
 405
 406    libc_hidden_proto (foo)
 407
 408    line and after the foo function definition:
 409
 410    int foo (int __bar)
 411    {
 412      return __bar;
 413    }
 414    libc_hidden_def (foo)
 415
 416    or
 417
 418    int foo (int __bar)
 419    {
 420      return __bar;
 421    }
 422    libc_hidden_weak (foo)
 423
 424    Similarly for global data.  If references to foo within libc.so should
 425    always go to foo defined in libc.so, then in include/foo.h you add:
 426
 427    libc_hidden_proto (foo)
 428
 429    line and after foo's definition:
 430
 431    int foo = INITIAL_FOO_VALUE;
 432    libc_hidden_data_def (foo)
 433
 434    or
 435
 436    int foo = INITIAL_FOO_VALUE;
 437    libc_hidden_data_weak (foo)
 438
 439    If foo is normally just an alias (strong or weak) to some other function,
 440    you should use the normal strong_alias first, then add libc_hidden_def
 441    or libc_hidden_weak:
 442
 443    int baz (int __bar)
 444    {
 445      return __bar;
 446    }
 447    strong_alias (baz, foo)
 448    libc_hidden_weak (foo)
 449
 450    If the function should be internal to multiple objects, say ld.so and
 451    libc.so, the best way is to use:
 452
 453    #if !defined NOT_IN_libc || defined IS_IN_rtld
 454    hidden_proto (foo)
 455    #endif
 456
 457    in include/foo.h and the normal macros at all function definitions
 458    depending on what DSO they belong to.
 459
 460    If versioned_symbol macro is used to define foo,
 461    libc_hidden_ver macro should be used, as in:
 462
 463    int __real_foo (int __bar)
 464    {
 465      return __bar;
 466    }
 467    versioned_symbol (libc, __real_foo, foo, GLIBC_2_1);
 468    libc_hidden_ver (__real_foo, foo)  */
 469
 470 #if defined SHARED && defined DO_VERSIONING && !defined NO_HIDDEN
 471 # ifndef __ASSEMBLER__
 472 #  define __hidden_proto_hiddenattr(attrs...) \
 473   __attribute__ ((visibility ("hidden"), ##attrs))
 474 #  define hidden_proto(name, attrs...) \
 475   __hidden_proto (name, __GI_##name, ##attrs)
 476 #  define __hidden_proto(name, internal, attrs...) \
 477   extern __typeof (name) name __asm__ (__hidden_asmname (#internal)) \
 478   __hidden_proto_hiddenattr (attrs);
 479 #  define __hidden_asmname(name) \
 480   __hidden_asmname1 (__USER_LABEL_PREFIX__, name)
 481 #  define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name)
 482 #  define __hidden_asmname2(prefix, name) #prefix name
 483 #  define __hidden_ver1(local, internal, name) \
 484   extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \
 485   extern __typeof (name) __EI_##name \
 486         __attribute__((alias (__hidden_asmname (#local))))
 487 #  define hidden_ver(local, name)       __hidden_ver1(local, __GI_##name, name);
 488 #  define hidden_data_ver(local, name)  hidden_ver(local, name)
 489 #  define hidden_def(name)              __hidden_ver1(__GI_##name, name, name);
 490 #  define hidden_data_def(name)         hidden_def(name)
 491 #  define hidden_weak(name) \
 492         __hidden_ver1(__GI_##name, name, name) __attribute__((weak));
 493 #  define hidden_data_weak(name)        hidden_weak(name)
 494 #  define hidden_nolink(name, lib, version) \
 495   __hidden_nolink1 (__GI_##name, __EI_##name, name, VERSION_##lib##_##version)
 496 #  define __hidden_nolink1(local, internal, name, version) \
 497   __hidden_nolink2 (local, internal, name, version)
 498 #  define __hidden_nolink2(local, internal, name, version) \
 499   extern __typeof (name) internal __attribute__ ((alias (#local))); \
 500   __hidden_nolink3 (local, internal, #name "@" #version)
 501 #  define __hidden_nolink3(local, internal, vername) \
 502   __asm__ (".symver " #internal ", " vername);
 503 # else
 504 /* For assembly, we need to do the opposite of what we do in C:
 505    in assembly gcc __REDIRECT stuff is not in place, so functions
 506    are defined by its normal name and we need to create the
 507    __GI_* alias to it, in C __REDIRECT causes the function definition
 508    to use __GI_* name and we need to add alias to the real name.
 509    There is no reason to use hidden_weak over hidden_def in assembly,
 510    but we provide it for consistency with the C usage.
 511    hidden_proto doesn't make sense for assembly but the equivalent
 512    is to call via the HIDDEN_JUMPTARGET macro instead of JUMPTARGET.  */
 513 #  define hidden_def(name)      strong_alias (name, __GI_##name)
 514 #  define hidden_weak(name)     hidden_def (name)
 515 #  define hidden_ver(local, name) strong_alias (local, __GI_##name)
 516 #  define hidden_data_def(name) strong_data_alias (name, __GI_##name)
 517 #  define hidden_data_weak(name)        hidden_data_def (name)
 518 #  define hidden_data_ver(local, name) strong_data_alias (local, __GI_##name)
 519 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 520 #   define HIDDEN_JUMPTARGET(name) .__GI_##name
 521 #  else
 522 #   define HIDDEN_JUMPTARGET(name) __GI_##name
 523 #  endif
 524 # endif
 525 #else
 526 # ifndef __ASSEMBLER__
 527 #  define hidden_proto(name, attrs...)
 528 # else
 529 #  define HIDDEN_JUMPTARGET(name) JUMPTARGET(name)
 530 # endif /* Not  __ASSEMBLER__ */
 531 # define hidden_weak(name)
 532 # define hidden_def(name)
 533 # define hidden_ver(local, name)
 534 # define hidden_data_weak(name)
 535 # define hidden_data_def(name)
 536 # define hidden_data_ver(local, name)
 537 # define hidden_nolink(name, lib, version)
 538 #endif
 539
 540 #if !defined NOT_IN_libc
 541 # define libc_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 542 # define libc_hidden_def(name) hidden_def (name)
 543 # define libc_hidden_weak(name) hidden_weak (name)
 544 # ifdef LINK_OBSOLETE_RPC
 545    /* libc_hidden_nolink_sunrpc should only get used in sunrpc code.  */
 546 #  define libc_hidden_nolink_sunrpc(name, version) hidden_def (name)
 547 # else
 548 #  define libc_hidden_nolink_sunrpc(name, version) hidden_nolink (name, libc, version)
 549 # endif
 550 # define libc_hidden_ver(local, name) hidden_ver (local, name)
 551 # define libc_hidden_data_def(name) hidden_data_def (name)
 552 # define libc_hidden_data_weak(name) hidden_data_weak (name)
 553 # define libc_hidden_data_ver(local, name) hidden_data_ver (local, name)
 554 #else
 555 # define libc_hidden_proto(name, attrs...)
 556 # define libc_hidden_def(name)
 557 # define libc_hidden_weak(name)
 558 # define libc_hidden_ver(local, name)
 559 # define libc_hidden_data_def(name)
 560 # define libc_hidden_data_weak(name)
 561 # define libc_hidden_data_ver(local, name)
 562 #endif
 563
 564 #if defined NOT_IN_libc && defined IS_IN_rtld
 565 # define rtld_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 566 # define rtld_hidden_def(name) hidden_def (name)
 567 # define rtld_hidden_weak(name) hidden_weak (name)
 568 # define rtld_hidden_ver(local, name) hidden_ver (local, name)
 569 # define rtld_hidden_data_def(name) hidden_data_def (name)
 570 # define rtld_hidden_data_weak(name) hidden_data_weak (name)
 571 # define rtld_hidden_data_ver(local, name) hidden_data_ver (local, name)
 572 #else
 573 # define rtld_hidden_proto(name, attrs...)
 574 # define rtld_hidden_def(name)
 575 # define rtld_hidden_weak(name)
 576 # define rtld_hidden_ver(local, name)
 577 # define rtld_hidden_data_def(name)
 578 # define rtld_hidden_data_weak(name)
 579 # define rtld_hidden_data_ver(local, name)
 580 #endif
 581
 582 #if defined NOT_IN_libc && defined IS_IN_libm
 583 # define libm_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 584 # define libm_hidden_def(name) hidden_def (name)
 585 # define libm_hidden_weak(name) hidden_weak (name)
 586 # define libm_hidden_ver(local, name) hidden_ver (local, name)
 587 # define libm_hidden_data_def(name) hidden_data_def (name)
 588 # define libm_hidden_data_weak(name) hidden_data_weak (name)
 589 # define libm_hidden_data_ver(local, name) hidden_data_ver (local, name)
 590 #else
 591 # define libm_hidden_proto(name, attrs...)
 592 # define libm_hidden_def(name)
 593 # define libm_hidden_weak(name)
 594 # define libm_hidden_ver(local, name)
 595 # define libm_hidden_data_def(name)
 596 # define libm_hidden_data_weak(name)
 597 # define libm_hidden_data_ver(local, name)
 598 #endif
 599
 600 #if defined NOT_IN_libc && defined IS_IN_libresolv
 601 # define libresolv_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 602 # define libresolv_hidden_def(name) hidden_def (name)
 603 # define libresolv_hidden_weak(name) hidden_weak (name)
 604 # define libresolv_hidden_ver(local, name) hidden_ver (local, name)
 605 # define libresolv_hidden_data_def(name) hidden_data_def (name)
 606 # define libresolv_hidden_data_weak(name) hidden_data_weak (name)
 607 # define libresolv_hidden_data_ver(local, name) hidden_data_ver (local, name)
 608 #else
 609 # define libresolv_hidden_proto(name, attrs...)
 610 # define libresolv_hidden_def(name)
 611 # define libresolv_hidden_weak(name)
 612 # define libresolv_hidden_ver(local, name)
 613 # define libresolv_hidden_data_def(name)
 614 # define libresolv_hidden_data_weak(name)
 615 # define libresolv_hidden_data_ver(local, name)
 616 #endif
 617
 618 #if defined NOT_IN_libc && defined IS_IN_librt
 619 # define librt_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 620 # define librt_hidden_def(name) hidden_def (name)
 621 # define librt_hidden_weak(name) hidden_weak (name)
 622 # define librt_hidden_ver(local, name) hidden_ver (local, name)
 623 # define librt_hidden_data_def(name) hidden_data_def (name)
 624 # define librt_hidden_data_weak(name) hidden_data_weak (name)
 625 # define librt_hidden_data_ver(local, name) hidden_data_ver (local, name)
 626 #else
 627 # define librt_hidden_proto(name, attrs...)
 628 # define librt_hidden_def(name)
 629 # define librt_hidden_weak(name)
 630 # define librt_hidden_ver(local, name)
 631 # define librt_hidden_data_def(name)
 632 # define librt_hidden_data_weak(name)
 633 # define librt_hidden_data_ver(local, name)
 634 #endif
 635
 636 #if defined NOT_IN_libc && defined IS_IN_libdl
 637 # define libdl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 638 # define libdl_hidden_def(name) hidden_def (name)
 639 # define libdl_hidden_weak(name) hidden_weak (name)
 640 # define libdl_hidden_ver(local, name) hidden_ver (local, name)
 641 # define libdl_hidden_data_def(name) hidden_data_def (name)
 642 # define libdl_hidden_data_weak(name) hidden_data_weak (name)
 643 # define libdl_hidden_data_ver(local, name) hidden_data_ver (local, name)
 644 #else
 645 # define libdl_hidden_proto(name, attrs...)
 646 # define libdl_hidden_def(name)
 647 # define libdl_hidden_weak(name)
 648 # define libdl_hidden_ver(local, name)
 649 # define libdl_hidden_data_def(name)
 650 # define libdl_hidden_data_weak(name)
 651 # define libdl_hidden_data_ver(local, name)
 652 #endif
 653
 654 #if defined NOT_IN_libc && defined IS_IN_libnss_files
 655 # define libnss_files_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 656 # define libnss_files_hidden_def(name) hidden_def (name)
 657 # define libnss_files_hidden_weak(name) hidden_weak (name)
 658 # define libnss_files_hidden_ver(local, name) hidden_ver (local, name)
 659 # define libnss_files_hidden_data_def(name) hidden_data_def (name)
 660 # define libnss_files_hidden_data_weak(name) hidden_data_weak (name)
 661 # define libnss_files_hidden_data_ver(local, name) hidden_data_ver(local, name)
 662 #else
 663 # define libnss_files_hidden_proto(name, attrs...)
 664 # define libnss_files_hidden_def(name)
 665 # define libnss_files_hidden_weak(name)
 666 # define libnss_files_hidden_ver(local, name)
 667 # define libnss_files_hidden_data_def(name)
 668 # define libnss_files_hidden_data_weak(name)
 669 # define libnss_files_hidden_data_ver(local, name)
 670 #endif
 671
 672 #if defined NOT_IN_libc && defined IS_IN_libnsl
 673 # define libnsl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 674 # define libnsl_hidden_def(name) hidden_def (name)
 675 # define libnsl_hidden_weak(name) hidden_weak (name)
 676 # define libnsl_hidden_ver(local, name) hidden_ver (local, name)
 677 # define libnsl_hidden_data_def(name) hidden_data_def (name)
 678 # define libnsl_hidden_data_weak(name) hidden_data_weak (name)
 679 # define libnsl_hidden_data_ver(local, name) hidden_data_ver (local, name)
 680 #else
 681 # define libnsl_hidden_proto(name, attrs...)
 682 # define libnsl_hidden_def(name)
 683 # define libnsl_hidden_weak(name)
 684 # define libnsl_hidden_ver(local, name)
 685 # define libnsl_hidden_data_def(name)
 686 # define libnsl_hidden_data_weak(name)
 687 # define libnsl_hidden_data_ver(local, name)
 688 #endif
 689
 690 #if defined NOT_IN_libc && defined IS_IN_libnss_nisplus
 691 # define libnss_nisplus_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 692 # define libnss_nisplus_hidden_def(name) hidden_def (name)
 693 # define libnss_nisplus_hidden_weak(name) hidden_weak (name)
 694 # define libnss_nisplus_hidden_ver(local, name) hidden_ver (local, name)
 695 # define libnss_nisplus_hidden_data_def(name) hidden_data_def (name)
 696 # define libnss_nisplus_hidden_data_weak(name) hidden_data_weak (name)
 697 # define libnss_nisplus_hidden_data_ver(local, name) hidden_data_ver (local, name)
 698 #else
 699 # define libnss_nisplus_hidden_proto(name, attrs...)
 700 # define libnss_nisplus_hidden_def(name)
 701 # define libnss_nisplus_hidden_weak(name)
 702 # define libnss_nisplus_hidden_ver(local, name)
 703 # define libnss_nisplus_hidden_data_def(name)
 704 # define libnss_nisplus_hidden_data_weak(name)
 705 # define libnss_nisplus_hidden_data_ver(local, name)
 706 #endif
 707
 708 #define libc_hidden_builtin_proto(name, attrs...) libc_hidden_proto (name, ##attrs)
 709 #define libc_hidden_builtin_def(name) libc_hidden_def (name)
 710 #define libc_hidden_builtin_weak(name) libc_hidden_weak (name)
 711 #define libc_hidden_builtin_ver(local, name) libc_hidden_ver (local, name)
 712 #ifdef __ASSEMBLER__
 713 # define HIDDEN_BUILTIN_JUMPTARGET(name) HIDDEN_JUMPTARGET(name)
 714 #endif
 715
 716 #if defined NOT_IN_libc && defined IS_IN_libutil
 717 # define libutil_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 718 # define libutil_hidden_def(name) hidden_def (name)
 719 # define libutil_hidden_weak(name) hidden_weak (name)
 720 # define libutil_hidden_ver(local, name) hidden_ver (local, name)
 721 # define libutil_hidden_data_def(name) hidden_data_def (name)
 722 # define libutil_hidden_data_weak(name) hidden_data_weak (name)
 723 # define libutil_hidden_data_ver(local, name) hidden_data_ver (local, name)
 724 #else
 725 # define libutil_hidden_proto(name, attrs...)
 726 # define libutil_hidden_def(name)
 727 # define libutil_hidden_weak(name)
 728 # define libutil_hidden_ver(local, name)
 729 # define libutil_hidden_data_def(name)
 730 # define libutil_hidden_data_weak(name)
 731 # define libutil_hidden_data_ver(local, name)
 732 #endif
 733
 734 /* Get some dirty hacks.  */
 735 #include <symbol-hacks.h>
 736
 737 /* Move compatibility symbols out of the way by placing them all in a
 738    special section.  */
 739 #ifndef __ASSEMBLER__
 740 # define attribute_compat_text_section \
 741     __attribute__ ((section (".text.compat")))
 742 # define attribute_compat_data_section \
 743     __attribute__ ((section (".data.compat")))
 744 #else
 745 # define compat_text_section .section ".text.compat", "ax";
 746 # define compat_data_section .section ".data.compat", "aw";
 747 #endif
 748
 749 /* Marker used for indirection function symbols.  */
 750 #define libc_ifunc(name, expr)                                          \
 751   extern void *name##_ifunc (void) __asm__ (#name);                     \
 752   void *name##_ifunc (void)                                             \
 753   {                                                                     \
 754     INIT_ARCH ();                                                       \
 755     __typeof (name) *res = expr;                                        \
 756     return res;                                                         \
 757   }                                                                     \
 758   __asm__ (".type " #name ", %gnu_indirect_function");
 759
 760 /* The body of the function is supposed to use __get_cpu_features
 761    which will, if necessary, initialize the data first.  */
 762 #define libm_ifunc(name, expr)                                          \
 763   extern void *name##_ifunc (void) __asm__ (#name);                     \
 764   void *name##_ifunc (void)                                             \
 765   {                                                                     \
 766     __typeof (name) *res = expr;                                        \
 767     return res;                                                         \
 768   }                                                                     \
 769   __asm__ (".type " #name ", %gnu_indirect_function");
 770
 771 #ifdef HAVE_ASM_SET_DIRECTIVE
 772 # define libc_ifunc_hidden_def1(local, name)                            \
 773     __asm__ (".globl " #local "\n\t"                                    \
 774              ".hidden " #local "\n\t"                                   \
 775              ".set " #local ", " #name);
 776 #else
 777 # define libc_ifunc_hidden_def1(local, name)                            \
 778     __asm__ (".globl " #local "\n\t"                                    \
 779              ".hidden " #local "\n\t"                                   \
 780              #local " = " #name);
 781 #endif
 782
 783 #define libc_ifunc_hidden_def(name) \
 784   libc_ifunc_hidden_def1 (__GI_##name, name)
 785
 786 #endif /* libc-symbols.h */