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) 1995-2014 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, #name " is not implemented and will always fail")
 232
 233 /* Warning for linking functions calling dlopen into static binaries.  */
 234 #ifdef SHARED
 235 #define static_link_warning(name)
 236 #else
 237 #define static_link_warning(name) static_link_warning1(name)
 238 #define static_link_warning1(name) \
 239   link_warning(name, "Using '" #name "' in statically linked applications \
 240 requires at runtime the shared libraries from the glibc version used \
 241 for linking")
 242 #endif
 243
 244 /* Declare SYMBOL to be TYPE (`function' or `object') of SIZE bytes
 245    alias to ORIGINAL, when the assembler supports such declarations
 246    (such as in ELF).
 247    This is only necessary when defining something in assembly, or playing
 248    funny alias games where the size should be other than what the compiler
 249    thinks it is.  */
 250 #define declare_symbol_alias(symbol, original, type, size) \
 251   declare_symbol_alias_1 (symbol, original, type, size)
 252 #ifdef __ASSEMBLER__
 253 # define declare_symbol_alias_1(symbol, original, type, size) \
 254    strong_alias (original, symbol); \
 255    .type C_SYMBOL_NAME (symbol), %##type; \
 256    .size C_SYMBOL_NAME (symbol), size
 257 #else /* Not __ASSEMBLER__.  */
 258 # define declare_symbol_alias_1(symbol, original, type, size) \
 259    asm (".globl " __SYMBOL_PREFIX #symbol \
 260         "\n\t" declare_symbol_alias_1_alias (symbol, original) \
 261         "\n\t.type " __SYMBOL_PREFIX #symbol ", " \
 262         "%" #type \
 263         "\n\t.size " __SYMBOL_PREFIX #symbol ", " #size);
 264 # ifdef HAVE_ASM_SET_DIRECTIVE
 265 #  define declare_symbol_alias_1_alias(symbol, original) \
 266      ".set " __SYMBOL_PREFIX #symbol ", " __SYMBOL_PREFIX #original
 267 # else
 268 #  define declare_symbol_alias_1_alias(symbol, original) \
 269      __SYMBOL_PREFIX #symbol " = " __SYMBOL_PREFIX #original
 270 # endif /* HAVE_ASM_SET_DIRECTIVE */
 271 #endif /* __ASSEMBLER__ */
 272
 273
 274 /*
 275 \f
 276 */
 277
 278 /* Symbol set support macros.  */
 279
 280 /* Make SYMBOL, which is in the text segment, an element of SET.  */
 281 #define text_set_element(set, symbol)   _elf_set_element(set, symbol)
 282 /* Make SYMBOL, which is in the data segment, an element of SET.  */
 283 #define data_set_element(set, symbol)   _elf_set_element(set, symbol)
 284 /* Make SYMBOL, which is in the bss segment, an element of SET.  */
 285 #define bss_set_element(set, symbol)    _elf_set_element(set, symbol)
 286
 287 /* These are all done the same way in ELF.
 288    There is a new section created for each set.  */
 289 #ifdef SHARED
 290 /* When building a shared library, make the set section writable,
 291    because it will need to be relocated at run time anyway.  */
 292 # define _elf_set_element(set, symbol) \
 293   static const void *__elf_set_##set##_element_##symbol##__ \
 294     __attribute__ ((used, section (#set))) = &(symbol)
 295 #else
 296 # define _elf_set_element(set, symbol) \
 297   static const void *const __elf_set_##set##_element_##symbol##__ \
 298     __attribute__ ((used, section (#set))) = &(symbol)
 299 #endif
 300
 301 /* Define SET as a symbol set.  This may be required (it is in a.out) to
 302    be able to use the set's contents.  */
 303 #define symbol_set_define(set)  symbol_set_declare(set)
 304
 305 /* Declare SET for use in this module, if defined in another module.
 306    In a shared library, this is always local to that shared object.
 307    For static linking, the set might be wholly absent and so we use
 308    weak references.  */
 309 #define symbol_set_declare(set) \
 310   extern char const __start_##set[] __symbol_set_attribute; \
 311   extern char const __stop_##set[] __symbol_set_attribute;
 312 #ifdef SHARED
 313 # define __symbol_set_attribute attribute_hidden
 314 #else
 315 # define __symbol_set_attribute __attribute__ ((weak))
 316 #endif
 317
 318 /* Return a pointer (void *const *) to the first element of SET.  */
 319 #define symbol_set_first_element(set)   ((void *const *) (&__start_##set))
 320
 321 /* Return true iff PTR (a void *const *) has been incremented
 322    past the last element in SET.  */
 323 #define symbol_set_end_p(set, ptr) ((ptr) >= (void *const *) &__stop_##set)
 324
 325 #ifdef SHARED
 326 # define symbol_version(real, name, version) \
 327      _symbol_version(real, name, version)
 328 # define default_symbol_version(real, name, version) \
 329      _default_symbol_version(real, name, version)
 330 # ifdef __ASSEMBLER__
 331 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 332 #   define _symbol_version(real, name, version) \
 333      .symver real, name##@##version ASM_LINE_SEP                        \
 334      .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##version)
 335 #   define _default_symbol_version(real, name, version) \
 336      .symver real, name##@##@##version ASM_LINE_SEP                     \
 337      .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##@##version)
 338 #  else
 339 #   define _symbol_version(real, name, version) \
 340      .symver real, name##@##version
 341 #   define _default_symbol_version(real, name, version) \
 342      .symver real, name##@##@##version
 343 #  endif
 344 # else
 345 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 346 #   define _symbol_version(real, name, version) \
 347      __asm__ (".symver " #real "," #name "@" #version "\n\t"    \
 348               ".symver ." #real ",." #name "@" #version)
 349 #   define _default_symbol_version(real, name, version) \
 350      __asm__ (".symver " #real "," #name "@@" #version "\n\t"   \
 351               ".symver ." #real ",." #name "@@" #version)
 352 #  else
 353 #   define _symbol_version(real, name, version) \
 354      __asm__ (".symver " #real "," #name "@" #version)
 355 #   define _default_symbol_version(real, name, version) \
 356      __asm__ (".symver " #real "," #name "@@" #version)
 357 #  endif
 358 # endif
 359 #else
 360 # define symbol_version(real, name, version)
 361 # define default_symbol_version(real, name, version) \
 362   strong_alias(real, name)
 363 #endif
 364
 365 #if defined SHARED || defined LIBC_NONSHARED
 366 # define attribute_hidden __attribute__ ((visibility ("hidden")))
 367 #else
 368 # define attribute_hidden
 369 #endif
 370
 371 #define attribute_tls_model_ie __attribute__ ((tls_model ("initial-exec")))
 372
 373 #define attribute_relro __attribute__ ((section (".data.rel.ro")))
 374
 375 /* Handling on non-exported internal names.  We have to do this only
 376    for shared code.  */
 377 #ifdef SHARED
 378 # define INTUSE(name) name##_internal
 379 # define INTDEF(name) strong_alias (name, name##_internal)
 380 # define INTVARDEF(name) \
 381   _INTVARDEF (name, name##_internal)
 382 # define _INTVARDEF(name, aliasname) \
 383   extern __typeof (name) aliasname __attribute__ ((alias (#name), \
 384                                                    visibility ("hidden")));
 385 # define INTDEF2(name, newname) strong_alias (name, newname##_internal)
 386 # define INTVARDEF2(name, newname) _INTVARDEF (name, newname##_internal)
 387 #else
 388 # define INTUSE(name) name
 389 # define INTDEF(name)
 390 # define INTVARDEF(name)
 391 # define INTDEF2(name, newname)
 392 # define INTVARDEF2(name, newname)
 393 #endif
 394
 395 /* The following macros are used for PLT bypassing within libc.so
 396    (and if needed other libraries similarly).
 397    First of all, you need to have the function prototyped somewhere,
 398    say in foo/foo.h:
 399
 400    int foo (int __bar);
 401
 402    If calls to foo within libc.so should always go to foo defined in libc.so,
 403    then in include/foo.h you add:
 404
 405    libc_hidden_proto (foo)
 406
 407    line and after the foo function definition:
 408
 409    int foo (int __bar)
 410    {
 411      return __bar;
 412    }
 413    libc_hidden_def (foo)
 414
 415    or
 416
 417    int foo (int __bar)
 418    {
 419      return __bar;
 420    }
 421    libc_hidden_weak (foo)
 422
 423    Similarly for global data.  If references to foo within libc.so should
 424    always go to foo defined in libc.so, then in include/foo.h you add:
 425
 426    libc_hidden_proto (foo)
 427
 428    line and after foo's definition:
 429
 430    int foo = INITIAL_FOO_VALUE;
 431    libc_hidden_data_def (foo)
 432
 433    or
 434
 435    int foo = INITIAL_FOO_VALUE;
 436    libc_hidden_data_weak (foo)
 437
 438    If foo is normally just an alias (strong or weak) to some other function,
 439    you should use the normal strong_alias first, then add libc_hidden_def
 440    or libc_hidden_weak:
 441
 442    int baz (int __bar)
 443    {
 444      return __bar;
 445    }
 446    strong_alias (baz, foo)
 447    libc_hidden_weak (foo)
 448
 449    If the function should be internal to multiple objects, say ld.so and
 450    libc.so, the best way is to use:
 451
 452    #if !defined NOT_IN_libc || defined IS_IN_rtld
 453    hidden_proto (foo)
 454    #endif
 455
 456    in include/foo.h and the normal macros at all function definitions
 457    depending on what DSO they belong to.
 458
 459    If versioned_symbol macro is used to define foo,
 460    libc_hidden_ver macro should be used, as in:
 461
 462    int __real_foo (int __bar)
 463    {
 464      return __bar;
 465    }
 466    versioned_symbol (libc, __real_foo, foo, GLIBC_2_1);
 467    libc_hidden_ver (__real_foo, foo)  */
 468
 469 #if defined SHARED && !defined NO_HIDDEN
 470 # ifndef __ASSEMBLER__
 471 #  define __hidden_proto_hiddenattr(attrs...) \
 472   __attribute__ ((visibility ("hidden"), ##attrs))
 473 #  define hidden_proto(name, attrs...) \
 474   __hidden_proto (name, , __GI_##name, ##attrs)
 475 #  define hidden_tls_proto(name, attrs...) \
 476   __hidden_proto (name, __thread, __GI_##name, ##attrs)
 477 #  define __hidden_proto(name, thread, internal, attrs...)           \
 478   extern thread __typeof (name) name __asm__ (__hidden_asmname (#internal)) \
 479   __hidden_proto_hiddenattr (attrs);
 480 #  define __hidden_asmname(name) \
 481   __hidden_asmname1 (__USER_LABEL_PREFIX__, name)
 482 #  define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name)
 483 #  define __hidden_asmname2(prefix, name) #prefix name
 484 #  define __hidden_ver1(local, internal, name) \
 485   extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \
 486   extern __typeof (name) __EI_##name \
 487         __attribute__((alias (__hidden_asmname (#local))))
 488 #  define hidden_ver(local, name)       __hidden_ver1(local, __GI_##name, name);
 489 #  define hidden_data_ver(local, name)  hidden_ver(local, name)
 490 #  define hidden_def(name)              __hidden_ver1(__GI_##name, name, name);
 491 #  define hidden_data_def(name)         hidden_def(name)
 492 #  define hidden_weak(name) \
 493         __hidden_ver1(__GI_##name, name, name) __attribute__((weak));
 494 #  define hidden_data_weak(name)        hidden_weak(name)
 495 #  define hidden_nolink(name, lib, version) \
 496   __hidden_nolink1 (__GI_##name, __EI_##name, name, VERSION_##lib##_##version)
 497 #  define __hidden_nolink1(local, internal, name, version) \
 498   __hidden_nolink2 (local, internal, name, version)
 499 #  define __hidden_nolink2(local, internal, name, version) \
 500   extern __typeof (name) internal __attribute__ ((alias (#local))); \
 501   __hidden_nolink3 (local, internal, #name "@" #version)
 502 #  define __hidden_nolink3(local, internal, vername) \
 503   __asm__ (".symver " #internal ", " vername);
 504 # else
 505 /* For assembly, we need to do the opposite of what we do in C:
 506    in assembly gcc __REDIRECT stuff is not in place, so functions
 507    are defined by its normal name and we need to create the
 508    __GI_* alias to it, in C __REDIRECT causes the function definition
 509    to use __GI_* name and we need to add alias to the real name.
 510    There is no reason to use hidden_weak over hidden_def in assembly,
 511    but we provide it for consistency with the C usage.
 512    hidden_proto doesn't make sense for assembly but the equivalent
 513    is to call via the HIDDEN_JUMPTARGET macro instead of JUMPTARGET.  */
 514 #  define hidden_def(name)      strong_alias (name, __GI_##name)
 515 #  define hidden_weak(name)     hidden_def (name)
 516 #  define hidden_ver(local, name) strong_alias (local, __GI_##name)
 517 #  define hidden_data_def(name) strong_data_alias (name, __GI_##name)
 518 #  define hidden_data_weak(name)        hidden_data_def (name)
 519 #  define hidden_data_ver(local, name) strong_data_alias (local, __GI_##name)
 520 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 521 #   define HIDDEN_JUMPTARGET(name) .__GI_##name
 522 #  else
 523 #   define HIDDEN_JUMPTARGET(name) __GI_##name
 524 #  endif
 525 # endif
 526 #else
 527 # ifndef __ASSEMBLER__
 528 #  define hidden_proto(name, attrs...)
 529 #  define hidden_tls_proto(name, attrs...)
 530 # else
 531 #  define HIDDEN_JUMPTARGET(name) JUMPTARGET(name)
 532 # endif /* Not  __ASSEMBLER__ */
 533 # define hidden_weak(name)
 534 # define hidden_def(name)
 535 # define hidden_ver(local, name)
 536 # define hidden_data_weak(name)
 537 # define hidden_data_def(name)
 538 # define hidden_data_ver(local, name)
 539 # define hidden_nolink(name, lib, version)
 540 #endif
 541
 542 #if !defined NOT_IN_libc
 543 # define libc_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 544 # define libc_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs)
 545 # define libc_hidden_def(name) hidden_def (name)
 546 # define libc_hidden_weak(name) hidden_weak (name)
 547 # ifdef LINK_OBSOLETE_RPC
 548    /* libc_hidden_nolink_sunrpc should only get used in sunrpc code.  */
 549 #  define libc_hidden_nolink_sunrpc(name, version) hidden_def (name)
 550 # else
 551 #  define libc_hidden_nolink_sunrpc(name, version) hidden_nolink (name, libc, version)
 552 # endif
 553 # define libc_hidden_ver(local, name) hidden_ver (local, name)
 554 # define libc_hidden_data_def(name) hidden_data_def (name)
 555 # define libc_hidden_data_weak(name) hidden_data_weak (name)
 556 # define libc_hidden_data_ver(local, name) hidden_data_ver (local, name)
 557 #else
 558 # define libc_hidden_proto(name, attrs...)
 559 # define libc_hidden_tls_proto(name, attrs...)
 560 # define libc_hidden_def(name)
 561 # define libc_hidden_weak(name)
 562 # define libc_hidden_ver(local, name)
 563 # define libc_hidden_data_def(name)
 564 # define libc_hidden_data_weak(name)
 565 # define libc_hidden_data_ver(local, name)
 566 #endif
 567
 568 #if defined NOT_IN_libc && defined IS_IN_rtld
 569 # define rtld_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 570 # define rtld_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs)
 571 # define rtld_hidden_def(name) hidden_def (name)
 572 # define rtld_hidden_weak(name) hidden_weak (name)
 573 # define rtld_hidden_ver(local, name) hidden_ver (local, name)
 574 # define rtld_hidden_data_def(name) hidden_data_def (name)
 575 # define rtld_hidden_data_weak(name) hidden_data_weak (name)
 576 # define rtld_hidden_data_ver(local, name) hidden_data_ver (local, name)
 577 #else
 578 # define rtld_hidden_proto(name, attrs...)
 579 # define rtld_hidden_tls_proto(name, attrs...)
 580 # define rtld_hidden_def(name)
 581 # define rtld_hidden_weak(name)
 582 # define rtld_hidden_ver(local, name)
 583 # define rtld_hidden_data_def(name)
 584 # define rtld_hidden_data_weak(name)
 585 # define rtld_hidden_data_ver(local, name)
 586 #endif
 587
 588 #if defined NOT_IN_libc && defined IS_IN_libm
 589 # define libm_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 590 # define libm_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs)
 591 # define libm_hidden_def(name) hidden_def (name)
 592 # define libm_hidden_weak(name) hidden_weak (name)
 593 # define libm_hidden_ver(local, name) hidden_ver (local, name)
 594 # define libm_hidden_data_def(name) hidden_data_def (name)
 595 # define libm_hidden_data_weak(name) hidden_data_weak (name)
 596 # define libm_hidden_data_ver(local, name) hidden_data_ver (local, name)
 597 #else
 598 # define libm_hidden_proto(name, attrs...)
 599 # define libm_hidden_tls_proto(name, attrs...)
 600 # define libm_hidden_def(name)
 601 # define libm_hidden_weak(name)
 602 # define libm_hidden_ver(local, name)
 603 # define libm_hidden_data_def(name)
 604 # define libm_hidden_data_weak(name)
 605 # define libm_hidden_data_ver(local, name)
 606 #endif
 607
 608 #if defined NOT_IN_libc && defined IS_IN_libresolv
 609 # define libresolv_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 610 # define libresolv_hidden_tls_proto(name, attrs...) \
 611   hidden_tls_proto (name, ##attrs)
 612 # define libresolv_hidden_def(name) hidden_def (name)
 613 # define libresolv_hidden_weak(name) hidden_weak (name)
 614 # define libresolv_hidden_ver(local, name) hidden_ver (local, name)
 615 # define libresolv_hidden_data_def(name) hidden_data_def (name)
 616 # define libresolv_hidden_data_weak(name) hidden_data_weak (name)
 617 # define libresolv_hidden_data_ver(local, name) hidden_data_ver (local, name)
 618 #else
 619 # define libresolv_hidden_proto(name, attrs...)
 620 # define libresolv_hidden_tls_proto(name, attrs...)
 621 # define libresolv_hidden_def(name)
 622 # define libresolv_hidden_weak(name)
 623 # define libresolv_hidden_ver(local, name)
 624 # define libresolv_hidden_data_def(name)
 625 # define libresolv_hidden_data_weak(name)
 626 # define libresolv_hidden_data_ver(local, name)
 627 #endif
 628
 629 #if defined NOT_IN_libc && defined IS_IN_librt
 630 # define librt_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 631 # define librt_hidden_tls_proto(name, attrs...) \
 632   hidden_tls_proto (name, ##attrs)
 633 # define librt_hidden_def(name) hidden_def (name)
 634 # define librt_hidden_weak(name) hidden_weak (name)
 635 # define librt_hidden_ver(local, name) hidden_ver (local, name)
 636 # define librt_hidden_data_def(name) hidden_data_def (name)
 637 # define librt_hidden_data_weak(name) hidden_data_weak (name)
 638 # define librt_hidden_data_ver(local, name) hidden_data_ver (local, name)
 639 #else
 640 # define librt_hidden_proto(name, attrs...)
 641 # define librt_hidden_tls_proto(name, attrs...)
 642 # define librt_hidden_def(name)
 643 # define librt_hidden_weak(name)
 644 # define librt_hidden_ver(local, name)
 645 # define librt_hidden_data_def(name)
 646 # define librt_hidden_data_weak(name)
 647 # define librt_hidden_data_ver(local, name)
 648 #endif
 649
 650 #if defined NOT_IN_libc && defined IS_IN_libdl
 651 # define libdl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 652 # define libdl_hidden_tls_proto(name, attrs...) \
 653   hidden_tls_proto (name, ##attrs)
 654 # define libdl_hidden_def(name) hidden_def (name)
 655 # define libdl_hidden_weak(name) hidden_weak (name)
 656 # define libdl_hidden_ver(local, name) hidden_ver (local, name)
 657 # define libdl_hidden_data_def(name) hidden_data_def (name)
 658 # define libdl_hidden_data_weak(name) hidden_data_weak (name)
 659 # define libdl_hidden_data_ver(local, name) hidden_data_ver (local, name)
 660 #else
 661 # define libdl_hidden_proto(name, attrs...)
 662 # define libdl_hidden_tls_proto(name, attrs...)
 663 # define libdl_hidden_def(name)
 664 # define libdl_hidden_weak(name)
 665 # define libdl_hidden_ver(local, name)
 666 # define libdl_hidden_data_def(name)
 667 # define libdl_hidden_data_weak(name)
 668 # define libdl_hidden_data_ver(local, name)
 669 #endif
 670
 671 #if defined NOT_IN_libc && defined IS_IN_libnss_files
 672 # define libnss_files_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 673 # define libnss_files_hidden_tls_proto(name, attrs...) \
 674   hidden_tls_proto (name, ##attrs)
 675 # define libnss_files_hidden_def(name) hidden_def (name)
 676 # define libnss_files_hidden_weak(name) hidden_weak (name)
 677 # define libnss_files_hidden_ver(local, name) hidden_ver (local, name)
 678 # define libnss_files_hidden_data_def(name) hidden_data_def (name)
 679 # define libnss_files_hidden_data_weak(name) hidden_data_weak (name)
 680 # define libnss_files_hidden_data_ver(local, name) hidden_data_ver(local, name)
 681 #else
 682 # define libnss_files_hidden_proto(name, attrs...)
 683 # define libnss_files_hidden_tls_proto(name, attrs...)
 684 # define libnss_files_hidden_def(name)
 685 # define libnss_files_hidden_weak(name)
 686 # define libnss_files_hidden_ver(local, name)
 687 # define libnss_files_hidden_data_def(name)
 688 # define libnss_files_hidden_data_weak(name)
 689 # define libnss_files_hidden_data_ver(local, name)
 690 #endif
 691
 692 #if defined NOT_IN_libc && defined IS_IN_libnsl
 693 # define libnsl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 694 # define libnsl_hidden_tls_proto(name, attrs...) \
 695   hidden_tls_proto (name, ##attrs)
 696 # define libnsl_hidden_def(name) hidden_def (name)
 697 # define libnsl_hidden_weak(name) hidden_weak (name)
 698 # define libnsl_hidden_ver(local, name) hidden_ver (local, name)
 699 # define libnsl_hidden_data_def(name) hidden_data_def (name)
 700 # define libnsl_hidden_data_weak(name) hidden_data_weak (name)
 701 # define libnsl_hidden_data_ver(local, name) hidden_data_ver (local, name)
 702 #else
 703 # define libnsl_hidden_proto(name, attrs...)
 704 # define libnsl_hidden_tls_proto(name, attrs...)
 705 # define libnsl_hidden_def(name)
 706 # define libnsl_hidden_weak(name)
 707 # define libnsl_hidden_ver(local, name)
 708 # define libnsl_hidden_data_def(name)
 709 # define libnsl_hidden_data_weak(name)
 710 # define libnsl_hidden_data_ver(local, name)
 711 #endif
 712
 713 #if defined NOT_IN_libc && defined IS_IN_libnss_nisplus
 714 # define libnss_nisplus_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 715 # define libnss_nisplus_hidden_tls_proto(name, attrs...) \
 716   hidden_tls_proto (name, ##attrs)
 717 # define libnss_nisplus_hidden_def(name) hidden_def (name)
 718 # define libnss_nisplus_hidden_weak(name) hidden_weak (name)
 719 # define libnss_nisplus_hidden_ver(local, name) hidden_ver (local, name)
 720 # define libnss_nisplus_hidden_data_def(name) hidden_data_def (name)
 721 # define libnss_nisplus_hidden_data_weak(name) hidden_data_weak (name)
 722 # define libnss_nisplus_hidden_data_ver(local, name) hidden_data_ver (local, name)
 723 #else
 724 # define libnss_nisplus_hidden_proto(name, attrs...)
 725 # define libnss_nisplus_hidden_tls_proto(name, attrs...)
 726 # define libnss_nisplus_hidden_def(name)
 727 # define libnss_nisplus_hidden_weak(name)
 728 # define libnss_nisplus_hidden_ver(local, name)
 729 # define libnss_nisplus_hidden_data_def(name)
 730 # define libnss_nisplus_hidden_data_weak(name)
 731 # define libnss_nisplus_hidden_data_ver(local, name)
 732 #endif
 733
 734 #define libc_hidden_builtin_proto(name, attrs...) libc_hidden_proto (name, ##attrs)
 735 #define libc_hidden_builtin_def(name) libc_hidden_def (name)
 736 #define libc_hidden_builtin_weak(name) libc_hidden_weak (name)
 737 #define libc_hidden_builtin_ver(local, name) libc_hidden_ver (local, name)
 738 #ifdef __ASSEMBLER__
 739 # define HIDDEN_BUILTIN_JUMPTARGET(name) HIDDEN_JUMPTARGET(name)
 740 #endif
 741
 742 #if defined NOT_IN_libc && defined IS_IN_libutil
 743 # define libutil_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
 744 # define libutil_hidden_tls_proto(name, attrs...) \
 745   hidden_tls_proto (name, ##attrs)
 746 # define libutil_hidden_def(name) hidden_def (name)
 747 # define libutil_hidden_weak(name) hidden_weak (name)
 748 # define libutil_hidden_ver(local, name) hidden_ver (local, name)
 749 # define libutil_hidden_data_def(name) hidden_data_def (name)
 750 # define libutil_hidden_data_weak(name) hidden_data_weak (name)
 751 # define libutil_hidden_data_ver(local, name) hidden_data_ver (local, name)
 752 #else
 753 # define libutil_hidden_proto(name, attrs...)
 754 # define libutil_hidden_tls_proto(name, attrs...)
 755 # define libutil_hidden_def(name)
 756 # define libutil_hidden_weak(name)
 757 # define libutil_hidden_ver(local, name)
 758 # define libutil_hidden_data_def(name)
 759 # define libutil_hidden_data_weak(name)
 760 # define libutil_hidden_data_ver(local, name)
 761 #endif
 762
 763 /* Get some dirty hacks.  */
 764 #include <symbol-hacks.h>
 765
 766 /* Move compatibility symbols out of the way by placing them all in a
 767    special section.  */
 768 #ifndef __ASSEMBLER__
 769 # define attribute_compat_text_section \
 770     __attribute__ ((section (".text.compat")))
 771 # define attribute_compat_data_section \
 772     __attribute__ ((section (".data.compat")))
 773 #else
 774 # define compat_text_section .section ".text.compat", "ax";
 775 # define compat_data_section .section ".data.compat", "aw";
 776 #endif
 777
 778 /* Marker used for indirection function symbols.  */
 779 #define libc_ifunc(name, expr)                                          \
 780   extern void *name##_ifunc (void) __asm__ (#name);                     \
 781   void *name##_ifunc (void)                                             \
 782   {                                                                     \
 783     INIT_ARCH ();                                                       \
 784     __typeof (name) *res = expr;                                        \
 785     return res;                                                         \
 786   }                                                                     \
 787   __asm__ (".type " #name ", %gnu_indirect_function");
 788
 789 /* The body of the function is supposed to use __get_cpu_features
 790    which will, if necessary, initialize the data first.  */
 791 #define libm_ifunc(name, expr)                                          \
 792   extern void *name##_ifunc (void) __asm__ (#name);                     \
 793   void *name##_ifunc (void)                                             \
 794   {                                                                     \
 795     __typeof (name) *res = expr;                                        \
 796     return res;                                                         \
 797   }                                                                     \
 798   __asm__ (".type " #name ", %gnu_indirect_function");
 799
 800 #ifdef HAVE_ASM_SET_DIRECTIVE
 801 # define libc_ifunc_hidden_def1(local, name)                            \
 802     __asm__ (".globl " #local "\n\t"                                    \
 803              ".hidden " #local "\n\t"                                   \
 804              ".set " #local ", " #name);
 805 #else
 806 # define libc_ifunc_hidden_def1(local, name)                            \
 807     __asm__ (".globl " #local "\n\t"                                    \
 808              ".hidden " #local "\n\t"                                   \
 809              #local " = " #name);
 810 #endif
 811
 812 #define libc_ifunc_hidden_def(name) \
 813   libc_ifunc_hidden_def1 (__GI_##name, name)
 814
 815 /* Add the compiler optimization to inhibit loop transformation to library
 816    calls.  This is used to avoid recursive calls in memset and memmove
 817    default implementations.  */
 818 #ifdef HAVE_CC_INHIBIT_LOOP_TO_LIBCALL
 819 # define inhibit_loop_to_libcall \
 820     __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
 821 #else
 822 # define inhibit_loop_to_libcall
 823 #endif
 824
 825 #endif /* libc-symbols.h */