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) 1995-1998,2000,2001,2002 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, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #ifndef _LIBC_SYMBOLS_H
  22 #define _LIBC_SYMBOLS_H 1
  23
  24 /* This file's macros are included implicitly in the compilation of every
  25    file in the C library by -imacros.
  26
  27    We include config.h which is generated by configure.
  28    It should define for us the following symbols:
  29
  30    * HAVE_ASM_SET_DIRECTIVE if we have `.set B, A' instead of `A = B'.
  31    * ASM_GLOBAL_DIRECTIVE with `.globl' or `.global'.
  32    * HAVE_GNU_LD if using GNU ld, with support for weak symbols in a.out,
  33    and for symbol set and warning messages extensions in a.out and ELF.
  34    * HAVE_ELF if using ELF, which supports weak symbols using `.weak'.
  35    * HAVE_ASM_WEAK_DIRECTIVE if we have weak symbols using `.weak'.
  36    * HAVE_ASM_WEAKEXT_DIRECTIVE if we have weak symbols using `.weakext'.
  37
  38    */
  39
  40 /* This is defined for the compilation of all C library code.  features.h
  41    tests this to avoid inclusion of stubs.h while compiling the library,
  42    before stubs.h has been generated.  Some library code that is shared
  43    with other packages also tests this symbol to see if it is being
  44    compiled as part of the C library.  We must define this before including
  45    config.h, because it makes some definitions conditional on whether libc
  46    itself is being compiled, or just some generator program.  */
  47 #define _LIBC   1
  48
  49 /* Enable declarations of GNU extensions, since we are compiling them.  */
  50 #define _GNU_SOURCE     1
  51 /* And we also need the data for the reentrant functions.  */
  52 #define _REENTRANT      1
  53
  54 #include <config.h>
  55
  56 /* The symbols in all the user (non-_) macros are C symbols.
  57    HAVE_GNU_LD without HAVE_ELF implies a.out.  */
  58
  59 #if defined HAVE_ASM_WEAK_DIRECTIVE || defined HAVE_ASM_WEAKEXT_DIRECTIVE
  60 # define HAVE_WEAK_SYMBOLS
  61 #endif
  62
  63 #ifndef __SYMBOL_PREFIX
  64 # ifdef NO_UNDERSCORES
  65 #  define __SYMBOL_PREFIX
  66 # else
  67 #  define __SYMBOL_PREFIX "_"
  68 # endif
  69 #endif
  70
  71 #ifndef C_SYMBOL_NAME
  72 # ifdef NO_UNDERSCORES
  73 #  define C_SYMBOL_NAME(name) name
  74 # else
  75 #  define C_SYMBOL_NAME(name) _##name
  76 # endif
  77 #endif
  78
  79 #ifndef ASM_LINE_SEP
  80 # define ASM_LINE_SEP ;
  81 #endif
  82
  83 #ifndef C_SYMBOL_DOT_NAME
  84 # define C_SYMBOL_DOT_NAME(name) .##name
  85 #endif
  86
  87 #ifndef __ASSEMBLER__
  88 /* GCC understands weak symbols and aliases; use its interface where
  89    possible, instead of embedded assembly language.  */
  90
  91 /* Define ALIASNAME as a strong alias for NAME.  */
  92 # define strong_alias(name, aliasname) _strong_alias(name, aliasname)
  93 # define _strong_alias(name, aliasname) \
  94   extern __typeof (name) aliasname __attribute__ ((alias (#name)));
  95
  96 /* This comes between the return type and function name in
  97    a function definition to make that definition weak.  */
  98 # define weak_function __attribute__ ((weak))
  99 # define weak_const_function __attribute__ ((weak, __const__))
 100
 101 # ifdef HAVE_WEAK_SYMBOLS
 102
 103 /* Define ALIASNAME as a weak alias for NAME.
 104    If weak aliases are not available, this defines a strong alias.  */
 105 #  define weak_alias(name, aliasname) _weak_alias (name, aliasname)
 106 #  define _weak_alias(name, aliasname) \
 107   extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
 108
 109 /* Declare SYMBOL as weak undefined symbol (resolved to 0 if not defined).  */
 110 #  define weak_extern(symbol) _weak_extern (symbol)
 111 #  ifdef HAVE_ASM_WEAKEXT_DIRECTIVE
 112 #   define _weak_extern(symbol) asm (".weakext " __SYMBOL_PREFIX #symbol);
 113 #  else
 114 #   define _weak_extern(symbol)    asm (".weak " __SYMBOL_PREFIX #symbol);
 115 #  endif
 116
 117 # else
 118
 119 #  define weak_alias(name, aliasname) strong_alias(name, aliasname)
 120 #  define weak_extern(symbol) /* Nothing. */
 121
 122 # endif
 123
 124 #else /* __ASSEMBLER__ */
 125
 126 # ifdef HAVE_ASM_SET_DIRECTIVE
 127 #  define strong_alias(original, alias)         \
 128   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 129   .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original)
 130 # else
 131 #  ifdef HAVE_ASM_GLOBAL_DOT_NAME
 132 #   define strong_alias(original, alias)        \
 133   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 134   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
 135   ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP   \
 136   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 137 #  else
 138 #   define strong_alias(original, alias)        \
 139   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 140   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 141 #  endif
 142 # endif
 143
 144 # ifdef HAVE_WEAK_SYMBOLS
 145 #  ifdef HAVE_ASM_WEAKEXT_DIRECTIVE
 146 #   define weak_alias(original, alias)  \
 147   .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original)
 148 #   define weak_extern(symbol)  \
 149   .weakext C_SYMBOL_NAME (symbol)
 150
 151 #  else /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
 152
 153 #   ifdef HAVE_ASM_GLOBAL_DOT_NAME
 154 #    define weak_alias(original, alias) \
 155   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP                      \
 156   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
 157   ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP   \
 158   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 159 #   else
 160 #    define weak_alias(original, alias) \
 161   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP      \
 162   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 163 #   endif
 164
 165 #   define weak_extern(symbol)  \
 166   .weak C_SYMBOL_NAME (symbol)
 167
 168 #  endif /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
 169
 170 # else /* ! HAVE_WEAK_SYMBOLS */
 171
 172 #  define weak_alias(original, alias) strong_alias(original, alias)
 173 #  define weak_extern(symbol) /* Nothing */
 174 # endif /* ! HAVE_WEAK_SYMBOLS */
 175
 176 #endif /* __ASSEMBLER__ */
 177
 178 /* On some platforms we can make internal function calls (i.e., calls of
 179    functions not exported) a bit faster by using a different calling
 180    convention.  */
 181 #ifndef internal_function
 182 # define internal_function      /* empty */
 183 #endif
 184
 185 /* Prepare for the case that `__builtin_expect' is not available.  */
 186 #ifndef HAVE_BUILTIN_EXPECT
 187 # define __builtin_expect(expr, val) (expr)
 188 #endif
 189
 190 /* Determine the return address.  */
 191 #define RETURN_ADDRESS(nr) \
 192   __builtin_extract_return_addr (__builtin_return_address (nr))
 193
 194 /* When a reference to SYMBOL is encountered, the linker will emit a
 195    warning message MSG.  */
 196 #ifdef HAVE_GNU_LD
 197 # ifdef HAVE_ELF
 198
 199 /* We want the .gnu.warning.SYMBOL section to be unallocated.  */
 200 #  ifdef HAVE_ASM_PREVIOUS_DIRECTIVE
 201 #   define __make_section_unallocated(section_string)   \
 202   asm (".section " section_string "\n\t.previous");
 203 #  elif defined HAVE_ASM_POPSECTION_DIRECTIVE
 204 #   define __make_section_unallocated(section_string)   \
 205   asm (".pushsection " section_string "\n\t.popsection");
 206 #  else
 207 #   define __make_section_unallocated(section_string)
 208 #  endif
 209
 210 /* Tacking on "\n\t#" to the section name makes gcc put it's bogus
 211    section attributes on what looks like a comment to the assembler.  */
 212 #  ifdef HAVE_SECTION_QUOTES
 213 #   define link_warning(symbol, msg) \
 214   __make_section_unallocated (".gnu.warning." #symbol) \
 215   static const char __evoke_link_warning_##symbol[]     \
 216     __attribute__ ((unused, section (".gnu.warning." #symbol "\"\n\t#\""))) \
 217     = msg;
 218 #  else
 219 #   define link_warning(symbol, msg) \
 220   __make_section_unallocated (".gnu.warning." #symbol) \
 221   static const char __evoke_link_warning_##symbol[]     \
 222     __attribute__ ((unused, section (".gnu.warning." #symbol "\n\t#"))) = msg;
 223 #  endif
 224 # else /* Not ELF: a.out */
 225 #  ifdef HAVE_XCOFF
 226 /* XCOFF does not support .stabs.
 227    The native aix linker will remove the .stab and .stabstr sections
 228    The gnu linker will have a fatal error if there is a relocation for
 229    symbol in the .stab section.  Silently disable this macro.  */
 230 #   define link_warning(symbol, msg)
 231 #  else
 232 #   define link_warning(symbol, msg)            \
 233      asm (".stabs \"" msg "\",30,0,0,0\n\t"     \
 234           ".stabs \"" __SYMBOL_PREFIX #symbol "\",1,0,0,0\n");
 235 #  endif /* XCOFF */
 236 # endif
 237 #else
 238 /* We will never be heard; they will all die horribly.  */
 239 # define link_warning(symbol, msg)
 240 #endif
 241
 242 /* A canned warning for sysdeps/stub functions.  */
 243 #define stub_warning(name) \
 244   link_warning (name, \
 245                 "warning: " #name " is not implemented and will always fail")
 246
 247 /*
 248 \f
 249 */
 250
 251 #ifdef HAVE_GNU_LD
 252
 253 /* Symbol set support macros.  */
 254
 255 # ifdef HAVE_ELF
 256
 257 /* Make SYMBOL, which is in the text segment, an element of SET.  */
 258 #  define text_set_element(set, symbol) _elf_set_element(set, symbol)
 259 /* Make SYMBOL, which is in the data segment, an element of SET.  */
 260 #  define data_set_element(set, symbol) _elf_set_element(set, symbol)
 261 /* Make SYMBOL, which is in the bss segment, an element of SET.  */
 262 #  define bss_set_element(set, symbol)  _elf_set_element(set, symbol)
 263
 264 /* These are all done the same way in ELF.
 265    There is a new section created for each set.  */
 266 #  ifdef SHARED
 267 /* When building a shared library, make the set section writable,
 268    because it will need to be relocated at run time anyway.  */
 269 #   define _elf_set_element(set, symbol) \
 270   static const void *__elf_set_##set##_element_##symbol##__ \
 271     __attribute__ ((unused, section (#set))) = &(symbol)
 272 #  else
 273 #   define _elf_set_element(set, symbol) \
 274   static const void *const __elf_set_##set##_element_##symbol##__ \
 275     __attribute__ ((unused, section (#set))) = &(symbol)
 276 #  endif
 277
 278 /* Define SET as a symbol set.  This may be required (it is in a.out) to
 279    be able to use the set's contents.  */
 280 #  define symbol_set_define(set)        symbol_set_declare(set)
 281
 282 /* Declare SET for use in this module, if defined in another module.  */
 283 #  define symbol_set_declare(set) \
 284   extern void *const __start_##set __attribute__ ((__weak__));          \
 285   extern void *const __stop_##set __attribute__ ((__weak__));           \
 286   weak_extern (__start_##set) weak_extern (__stop_##set)
 287
 288 /* Return a pointer (void *const *) to the first element of SET.  */
 289 #  define symbol_set_first_element(set) (&__start_##set)
 290
 291 /* Return true iff PTR (a void *const *) has been incremented
 292    past the last element in SET.  */
 293 #  define symbol_set_end_p(set, ptr)    ((ptr) >= &__stop_##set)
 294
 295 # else  /* Not ELF: a.out.  */
 296
 297 #  ifdef HAVE_XCOFF
 298 /* XCOFF does not support .stabs.
 299    The native aix linker will remove the .stab and .stabstr sections
 300    The gnu linker will have a fatal error if there is a relocation for
 301    symbol in the .stab section.  Silently disable these macros.  */
 302 #   define text_set_element(set, symbol)
 303 #   define data_set_element(set, symbol)
 304 #   define bss_set_element(set, symbol)
 305 #  else
 306 #   define text_set_element(set, symbol)        \
 307     asm (".stabs \"" __SYMBOL_PREFIX #set "\",23,0,0," __SYMBOL_PREFIX #symbol)
 308 #   define data_set_element(set, symbol)        \
 309     asm (".stabs \"" __SYMBOL_PREFIX #set "\",25,0,0," __SYMBOL_PREFIX #symbol)
 310 #   define bss_set_element(set, symbol) ?error Must use initialized data.
 311 #  endif /* XCOFF */
 312 #  define symbol_set_define(set)        void *const (set)[1];
 313 #  define symbol_set_declare(set)       extern void *const (set)[1];
 314
 315 #  define symbol_set_first_element(set) &(set)[1]
 316 #  define symbol_set_end_p(set, ptr)    (*(ptr) == 0)
 317
 318 # endif /* ELF.  */
 319 #else
 320 /* We cannot do anything in generial.  */
 321 # define text_set_element(set, symbol) asm ("")
 322 # define data_set_element(set, symbol) asm ("")
 323 # define bss_set_element(set, symbol) asm ("")
 324 # define symbol_set_define(set)         void *const (set)[1];
 325 # define symbol_set_declare(set)        extern void *const (set)[1];
 326
 327 # define symbol_set_first_element(set)  &(set)[1]
 328 # define symbol_set_end_p(set, ptr)     (*(ptr) == 0)
 329 #endif  /* Have GNU ld.  */
 330
 331 #if DO_VERSIONING
 332 # define symbol_version(real, name, version) \
 333      _symbol_version(real, name, version)
 334 # define default_symbol_version(real, name, version) \
 335      _default_symbol_version(real, name, version)
 336 # ifdef __ASSEMBLER__
 337 #  define _symbol_version(real, name, version) \
 338      .symver real, name##@##version
 339 #  define _default_symbol_version(real, name, version) \
 340      .symver real, name##@##@##version
 341 # else
 342 #  define _symbol_version(real, name, version) \
 343      __asm__ (".symver " #real "," #name "@" #version)
 344 #  define _default_symbol_version(real, name, version) \
 345      __asm__ (".symver " #real "," #name "@@" #version)
 346 # endif
 347 #else
 348 # define symbol_version(real, name, version)
 349 # define default_symbol_version(real, name, version) \
 350   strong_alias(real, name)
 351 #endif
 352
 353 #if defined HAVE_VISIBILITY_ATTRIBUTE && defined SHARED
 354 # define attribute_hidden __attribute__ ((visibility ("hidden")))
 355 #else
 356 # define attribute_hidden
 357 #endif
 358
 359 /* Handling on non-exported internal names.  We have to do this only
 360    for shared code.  */
 361 #ifdef SHARED
 362 # define INTUSE(name) name##_internal
 363 # define INTDEF(name) strong_alias (name, name##_internal)
 364 # define INTVARDEF(name) \
 365   _INTVARDEF (name, name##_internal)
 366 # if defined HAVE_VISIBILITY_ATTRIBUTE
 367 #  define _INTVARDEF(name, aliasname) \
 368   extern __typeof (name) aliasname __attribute__ ((alias (#name), \
 369                                                    visibility ("hidden")));
 370 # else
 371 #  define _INTVARDEF(name, aliasname) \
 372   extern __typeof (name) aliasname __attribute__ ((alias (#name)));
 373 # endif
 374 # define INTDEF2(name, newname) strong_alias (name, newname##_internal)
 375 # define INTVARDEF2(name, newname) _INTVARDEF (name, newname##_internal)
 376 #else
 377 # define INTUSE(name) name
 378 # define INTDEF(name)
 379 # define INTVARDEF(name)
 380 # define INTDEF2(name, newname)
 381 # define INTVARDEF2(name, newname)
 382 #endif
 383
 384 /* The following macros are used for PLT bypassing within libc.so
 385    (and if needed other libraries similarly).
 386    First of all, you need to have the function prototyped somewhere,
 387    say in foo/foo.h:
 388
 389    int foo (int __bar);
 390
 391    If calls to foo within libc.so should always go to foo defined in libc.so,
 392    then in include/foo.h you add:
 393
 394    libc_hidden_proto (foo)
 395
 396    line and after the foo function definition:
 397
 398    int foo (int __bar)
 399    {
 400      return __bar;
 401    }
 402    libc_hidden_def (foo)
 403
 404    or
 405
 406    int foo (int __bar)
 407    {
 408      return __bar;
 409    }
 410    libc_hidden_weak (foo)
 411
 412    If foo is normally just an alias (strong or weak) of some other function,
 413    you should use the normal strong_alias first, then add libc_hidden_def
 414    or libc_hidden_weak:
 415
 416    int baz (int __bar)
 417    {
 418      return __bar;
 419    }
 420    strong_alias (baz, foo)
 421    libc_hidden_weak (foo)
 422
 423    If the function should be internal to multiple objects, say ld.so and
 424    libc.so, the best way is to use:
 425
 426    #if !defined NOT_IN_libc || defined IS_IN_rtld
 427    hidden_proto (foo)
 428    #endif
 429
 430    in include/foo.h and the normal macros at all function definitions
 431    depending on what DSO they belong to.
 432
 433    If versioned_symbol macro is used to define foo,
 434    libc_hidden_ver macro should be used, as in:
 435
 436    int __real_foo (int __bar)
 437    {
 438      return __bar;
 439    }
 440    versioned_symbol (libc, __real_foo, foo, GLIBC_2_1);
 441    libc_hidden_ver (__real_foo, foo)  */
 442
 443 #if defined SHARED && defined DO_VERSIONING
 444 # ifndef __ASSEMBLER__
 445 #  ifdef HAVE_BROKEN_VISIBILITY_ATTRIBUTE
 446 #   define __hidden_proto_hiddenattr
 447 #  else
 448 #   define __hidden_proto_hiddenattr attribute_hidden
 449 #  endif
 450 #  ifndef HAVE_BROKEN_ALIAS_ATTRIBUTE
 451 #   define hidden_proto(name) __hidden_proto (name, __GI_##name)
 452 #  else
 453 #   define hidden_proto(name)
 454 #  endif
 455 #  define __hidden_proto(name, internal) \
 456   __typeof (name) internal; \
 457   __typeof (name) name __asm__ (__hidden_asmname (#internal)) \
 458   __hidden_proto_hiddenattr;
 459 #  define __hidden_asmname(name) \
 460   __hidden_asmname1 (__USER_LABEL_PREFIX__, name)
 461 #  define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name)
 462 #  define __hidden_asmname2(prefix, name) #prefix name
 463 #  ifdef HAVE_ASM_SET_DIRECTIVE
 464 #   define __hidden_def1(original, alias)                       \
 465   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 466   .set C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original)
 467 #  else
 468 #   ifdef HAVE_ASM_GLOBAL_DOT_NAME
 469 #    define __hidden_def1(original, alias)                      \
 470   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 471   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
 472   ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP   \
 473   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 474 #   else
 475 #    define __hidden_def1(original, alias)                      \
 476   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP       \
 477   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 478 #   endif
 479 #  endif
 480 #  define __hidden_def2(...) #__VA_ARGS__
 481 #  define __hidden_def3(...) __hidden_def2 (__VA_ARGS__)
 482 #  define hidden_def(name)                                      \
 483   __asm__ (__hidden_def3 (__hidden_def1 (__GI_##name, name)));
 484 #  define hidden_ver(local, name)                               \
 485   __asm__ (__hidden_def3 (__hidden_def1 (local, __GI_##name)));
 486 #  ifdef HAVE_WEAK_SYMBOLS
 487 #   ifdef HAVE_ASM_WEAKEXT_DIRECTIVE
 488 #    define __hidden_weak1(original, alias)                     \
 489   .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original)
 490 #   else /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
 491 #    ifdef HAVE_ASM_GLOBAL_DOT_NAME
 492 #     define __hidden_weak1(original, alias)                    \
 493   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP                      \
 494   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
 495   ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP   \
 496   C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
 497 #    else
 498 #     define __hidden_weak1(original, alias)                    \
 499   .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP                      \
 500   C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
 501 #    endif
 502 #   endif
 503 #   define hidden_weak(name)                                    \
 504   __asm__ (__hidden_def3 (__hidden_weak1 (__GI_##name, name)));
 505 #  else
 506 #   define hidden_weak(name) hidden_def (name)
 507 #  endif
 508 # else
 509 /* For assembly, we need to do the opposite of what we do in C:
 510    in assembly gcc __REDIRECT stuff is not in place, so functions
 511    are defined by its normal name and we need to create the
 512    __GI_* alias to it, in C __REDIRECT causes the function definition
 513    to use __GI_* name and we need to add alias to the real name.
 514    hidden_proto and hidden_weak don't make sense for assembly.  */
 515 #  define hidden_def(name) strong_alias (name, __GI_##name)
 516 #  define hidden_weak(name) weak_alias (name, __GI_##name)
 517 #  define hidden_ver(local, name) strong_alias (local, __GI_##name)
 518 # endif
 519 #else
 520 # ifndef __ASSEMBLY__
 521 #  define hidden_proto(name)
 522 #  define hidden_weak(name)
 523 # endif
 524 # define hidden_def(name)
 525 # define hidden_ver(local, name)
 526 #endif
 527
 528 #if !defined NOT_IN_libc
 529 # define libc_hidden_proto(name) hidden_proto (name)
 530 # define libc_hidden_def(name) hidden_def (name)
 531 # define libc_hidden_weak(name) hidden_weak (name)
 532 # define libc_hidden_ver(local, name) hidden_ver (local, name)
 533 #else
 534 # define libc_hidden_proto(name)
 535 # define libc_hidden_def(name)
 536 # define libc_hidden_weak(name)
 537 # define libc_hidden_ver(local, name)
 538 #endif
 539
 540 #if defined NOT_IN_libc && defined IS_IN_rtld
 541 # define rtld_hidden_proto(name) hidden_proto (name)
 542 # define rtld_hidden_def(name) hidden_def (name)
 543 # define rtld_hidden_weak(name) hidden_weak (name)
 544 # define rtld_hidden_ver(local, name) hidden_ver (local, name)
 545 #else
 546 # define rtld_hidden_proto(name)
 547 # define rtld_hidden_def(name)
 548 # define rtld_hidden_weak(name)
 549 # define rtld_hidden_ver(local, name)
 550 #endif
 551
 552 #if defined NOT_IN_libc && defined IS_IN_libm
 553 # define libm_hidden_proto(name) hidden_proto (name)
 554 # define libm_hidden_def(name) hidden_def (name)
 555 # define libm_hidden_weak(name) hidden_weak (name)
 556 # define libm_hidden_ver(local, name) hidden_ver (local, name)
 557 #else
 558 # define libm_hidden_proto(name)
 559 # define libm_hidden_def(name)
 560 # define libm_hidden_weak(name)
 561 # define libm_hidden_ver(local, name)
 562 #endif
 563
 564 #endif /* libc-symbols.h */