source: vendor/glibc/2005-05-xx/include/libc-symbols.h

Last change on this file was 2108, checked in by bird, 20 years ago

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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) 1995-1998,2000-2003,2004, 2005 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 * ASM_TYPE_DIRECTIVE_PREFIX with `@' or `#' or whatever for .type,
33 or leave it undefined if there is no .type directive.
34 * HAVE_GNU_LD if using GNU ld, with support for weak symbols in a.out,
35 and for symbol set and warning messages extensions in a.out and ELF.
36 * HAVE_ELF if using ELF, which supports weak symbols using `.weak'.
37 * HAVE_ASM_WEAK_DIRECTIVE if we have weak symbols using `.weak'.
38 * HAVE_ASM_WEAKEXT_DIRECTIVE if we have weak symbols using `.weakext'.
39
40 */
41
42/* This is defined for the compilation of all C library code. features.h
43 tests this to avoid inclusion of stubs.h while compiling the library,
44 before stubs.h has been generated. Some library code that is shared
45 with other packages also tests this symbol to see if it is being
46 compiled as part of the C library. We must define this before including
47 config.h, because it makes some definitions conditional on whether libc
48 itself is being compiled, or just some generator program. */
49#define _LIBC 1
50
51/* Enable declarations of GNU extensions, since we are compiling them. */
52#define _GNU_SOURCE 1
53/* And we also need the data for the reentrant functions. */
54#define _REENTRANT 1
55
56#include <config.h>
57
58/* The symbols in all the user (non-_) macros are C symbols.
59 HAVE_GNU_LD without HAVE_ELF implies a.out. */
60
61#if defined HAVE_ASM_WEAK_DIRECTIVE || defined HAVE_ASM_WEAKEXT_DIRECTIVE
62# define HAVE_WEAK_SYMBOLS
63#endif
64
65#ifndef __SYMBOL_PREFIX
66# ifdef NO_UNDERSCORES
67# define __SYMBOL_PREFIX
68# else
69# define __SYMBOL_PREFIX "_"
70# endif
71#endif
72
73#ifndef C_SYMBOL_NAME
74# ifdef NO_UNDERSCORES
75# define C_SYMBOL_NAME(name) name
76# else
77# define C_SYMBOL_NAME(name) _##name
78# endif
79#endif
80
81#ifndef ASM_LINE_SEP
82# define ASM_LINE_SEP ;
83#endif
84
85#ifdef HAVE_ASM_GLOBAL_DOT_NAME
86# ifndef C_SYMBOL_DOT_NAME
87# if defined __GNUC__ && defined __GNUC_MINOR__ \
88 && (__GNUC__ << 16) + __GNUC_MINOR__ >= (3 << 16) + 1
89# define C_SYMBOL_DOT_NAME(name) .name
90# else
91# define C_SYMBOL_DOT_NAME(name) .##name
92# endif
93# endif
94#endif
95
96#ifndef __ASSEMBLER__
97/* GCC understands weak symbols and aliases; use its interface where
98 possible, instead of embedded assembly language. */
99
100/* Define ALIASNAME as a strong alias for NAME. */
101# define strong_alias(name, aliasname) _strong_alias(name, aliasname)
102# define _strong_alias(name, aliasname) \
103 extern __typeof (name) aliasname __attribute__ ((alias (#name)));
104
105/* This comes between the return type and function name in
106 a function definition to make that definition weak. */
107# define weak_function __attribute__ ((weak))
108# define weak_const_function __attribute__ ((weak, __const__))
109
110# ifdef HAVE_WEAK_SYMBOLS
111
112/* Define ALIASNAME as a weak alias for NAME.
113 If weak aliases are not available, this defines a strong alias. */
114# define weak_alias(name, aliasname) _weak_alias (name, aliasname)
115# define _weak_alias(name, aliasname) \
116 extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
117
118/* Declare SYMBOL as weak undefined symbol (resolved to 0 if not defined). */
119# define weak_extern(symbol) _weak_extern (weak symbol)
120# define _weak_extern(expr) _Pragma (#expr)
121
122# else
123
124# define weak_alias(name, aliasname) strong_alias(name, aliasname)
125# define weak_extern(symbol) /* Nothing. */
126
127# endif
128
129#else /* __ASSEMBLER__ */
130
131# ifdef HAVE_ASM_SET_DIRECTIVE
132# ifdef HAVE_ASM_GLOBAL_DOT_NAME
133# define strong_alias(original, alias) \
134 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
135 .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) ASM_LINE_SEP \
136 ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \
137 .set C_SYMBOL_DOT_NAME (alias),C_SYMBOL_DOT_NAME (original)
138# define strong_data_alias(original, alias) \
139 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
140 .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original)
141# else
142# define strong_alias(original, alias) \
143 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
144 .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original)
145# define strong_data_alias(original, alias) strong_alias(original, alias)
146# endif
147# else
148# ifdef HAVE_ASM_GLOBAL_DOT_NAME
149# define strong_alias(original, alias) \
150 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
151 C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
152 ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \
153 C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
154# define strong_data_alias(original, alias) \
155 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
156 C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
157# else
158# define strong_alias(original, alias) \
159 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \
160 C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
161# define strong_data_alias(original, alias) strong_alias(original, alias)
162# endif
163# endif
164
165# ifdef HAVE_WEAK_SYMBOLS
166# ifdef HAVE_ASM_WEAKEXT_DIRECTIVE
167# ifdef HAVE_ASM_GLOBAL_DOT_NAME
168# define weak_alias(original, alias) \
169 .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) ASM_LINE_SEP \
170 .weakext C_SYMBOL_DOT_NAME (alias), C_SYMBOL_DOT_NAME (original)
171# else
172# define weak_alias(original, alias) \
173 .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original)
174# endif
175# define weak_extern(symbol) \
176 .weakext C_SYMBOL_NAME (symbol)
177
178# else /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
179
180# ifdef HAVE_ASM_GLOBAL_DOT_NAME
181# define weak_alias(original, alias) \
182 .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \
183 C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \
184 .weak C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \
185 C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original)
186# else
187# define weak_alias(original, alias) \
188 .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \
189 C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original)
190# endif
191
192# define weak_extern(symbol) \
193 .weak C_SYMBOL_NAME (symbol)
194
195# endif /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */
196
197# else /* ! HAVE_WEAK_SYMBOLS */
198
199# define weak_alias(original, alias) strong_alias(original, alias)
200# define weak_extern(symbol) /* Nothing */
201# endif /* ! HAVE_WEAK_SYMBOLS */
202
203#endif /* __ASSEMBLER__ */
204
205/* On some platforms we can make internal function calls (i.e., calls of
206 functions not exported) a bit faster by using a different calling
207 convention. */
208#ifndef internal_function
209# define internal_function /* empty */
210#endif
211
212/* Prepare for the case that `__builtin_expect' is not available. */
213#ifndef HAVE_BUILTIN_EXPECT
214# define __builtin_expect(expr, val) (expr)
215#endif
216
217/* Determine the return address. */
218#define RETURN_ADDRESS(nr) \
219 __builtin_extract_return_addr (__builtin_return_address (nr))
220
221/* When a reference to SYMBOL is encountered, the linker will emit a
222 warning message MSG. */
223#ifdef HAVE_GNU_LD
224# ifdef HAVE_ELF
225
226/* We want the .gnu.warning.SYMBOL section to be unallocated. */
227# ifdef HAVE_ASM_PREVIOUS_DIRECTIVE
228# define __make_section_unallocated(section_string) \
229 asm (".section " section_string "\n\t.previous");
230# elif defined HAVE_ASM_POPSECTION_DIRECTIVE
231# define __make_section_unallocated(section_string) \
232 asm (".pushsection " section_string "\n\t.popsection");
233# else
234# define __make_section_unallocated(section_string)
235# endif
236
237/* Tacking on "\n\t#" to the section name makes gcc put it's bogus
238 section attributes on what looks like a comment to the assembler. */
239# ifdef HAVE_SECTION_QUOTES
240# define __sec_comment "\"\n\t#\""
241# else
242# define __sec_comment "\n\t#"
243# endif
244# define link_warning(symbol, msg) \
245 __make_section_unallocated (".gnu.warning." #symbol) \
246 static const char __evoke_link_warning_##symbol[] \
247 __attribute__ ((used, section (".gnu.warning." #symbol __sec_comment))) \
248 = msg;
249# define libc_freeres_ptr(decl) \
250 __make_section_unallocated ("__libc_freeres_ptrs, \"aw\", %nobits") \
251 decl __attribute__ ((section ("__libc_freeres_ptrs" __sec_comment)))
252# define __libc_freeres_fn_section \
253 __attribute__ ((section ("__libc_freeres_fn")))
254# else /* Not ELF: a.out */
255# ifdef HAVE_XCOFF
256/* XCOFF does not support .stabs.
257 The native aix linker will remove the .stab and .stabstr sections
258 The gnu linker will have a fatal error if there is a relocation for
259 symbol in the .stab section. Silently disable this macro. */
260# define link_warning(symbol, msg)
261# else
262# define link_warning(symbol, msg) \
263 asm (".stabs \"" msg "\",30,0,0,0\n\t" \
264 ".stabs \"" __SYMBOL_PREFIX #symbol "\",1,0,0,0\n");
265# endif /* XCOFF */
266# define libc_freeres_ptr(decl) decl
267# define __libc_freeres_fn_section
268# endif
269#else
270/* We will never be heard; they will all die horribly. */
271# define link_warning(symbol, msg)
272# define libc_freeres_ptr(decl) decl
273# define __libc_freeres_fn_section
274#endif
275#define libc_freeres_fn(name) \
276 static void name (void) __attribute_used__ __libc_freeres_fn_section; \
277 text_set_element (__libc_subfreeres, name); \
278 static void name (void)
279
280/* A canned warning for sysdeps/stub functions. */
281#define stub_warning(name) \
282 __make_section_unallocated (".gnu.glibc-stub." #name) \
283 link_warning (name, \
284 "warning: " #name " is not implemented and will always fail")
285
286/* Warning for linking functions calling dlopen into static binaries. */
287#ifdef SHARED
288#define static_link_warning(name)
289#else
290#define static_link_warning(name) static_link_warning1(name)
291#define static_link_warning1(name) \
292 link_warning(name, "Using '" #name "' in statically linked applications \
293requires at runtime the shared libraries from the glibc version used \
294for linking")
295#endif
296
297/* Declare SYMBOL to be TYPE (`function' or `object') and of SIZE bytes,
298 when the assembler supports such declarations (such as in ELF).
299 This is only necessary when defining something in assembly, or playing
300 funny alias games where the size should be other than what the compiler
301 thinks it is. */
302#define declare_symbol(symbol, type, size) \
303 declare_symbol_1 (symbol, type, size)
304#ifdef ASM_TYPE_DIRECTIVE_PREFIX
305# ifdef __ASSEMBLER__
306# define declare_symbol_1(symbol, type, size) \
307 .type C_SYMBOL_NAME (symbol), \
308 declare_symbol_1_paste (ASM_TYPE_DIRECTIVE_PREFIX, type), size
309# define declare_symbol_1_paste(a, b) declare_symbol_1_paste_1 (a,b)
310# define declare_symbol_1_paste_1(a,b) a##b
311# else /* Not __ASSEMBLER__. */
312# define declare_symbol_1(symbol, type, size) \
313 asm (".type " __SYMBOL_PREFIX #symbol ", " \
314 declare_symbol_1_stringify (ASM_TYPE_DIRECTIVE_PREFIX) #type \
315 "\n\t.size " __SYMBOL_PREFIX #symbol ", " #size);
316# define declare_symbol_1_stringify(x) declare_symbol_1_stringify_1 (x)
317# define declare_symbol_1_stringify_1(x) #x
318# endif /* __ASSEMBLER__ */
319#else
320# define declare_symbol_1(symbol, type, size) /* Nothing. */
321#endif
322
323
324/*
325
326
327*/
328
329#ifdef HAVE_GNU_LD
330
331/* Symbol set support macros. */
332
333# ifdef HAVE_ELF
334
335/* Make SYMBOL, which is in the text segment, an element of SET. */
336# define text_set_element(set, symbol) _elf_set_element(set, symbol)
337/* Make SYMBOL, which is in the data segment, an element of SET. */
338# define data_set_element(set, symbol) _elf_set_element(set, symbol)
339/* Make SYMBOL, which is in the bss segment, an element of SET. */
340# define bss_set_element(set, symbol) _elf_set_element(set, symbol)
341
342/* These are all done the same way in ELF.
343 There is a new section created for each set. */
344# ifdef SHARED
345/* When building a shared library, make the set section writable,
346 because it will need to be relocated at run time anyway. */
347# define _elf_set_element(set, symbol) \
348 static const void *__elf_set_##set##_element_##symbol##__ \
349 __attribute__ ((used, section (#set))) = &(symbol)
350# else
351# define _elf_set_element(set, symbol) \
352 static const void *const __elf_set_##set##_element_##symbol##__ \
353 __attribute__ ((used, section (#set))) = &(symbol)
354# endif
355
356/* Define SET as a symbol set. This may be required (it is in a.out) to
357 be able to use the set's contents. */
358# define symbol_set_define(set) symbol_set_declare(set)
359
360/* Declare SET for use in this module, if defined in another module.
361 In a shared library, this is always local to that shared object.
362 For static linking, the set might be wholly absent and so we use
363 weak references. */
364# define symbol_set_declare(set) \
365 extern char const __start_##set[] __symbol_set_attribute; \
366 extern char const __stop_##set[] __symbol_set_attribute;
367# ifdef SHARED
368# define __symbol_set_attribute attribute_hidden
369# else
370# define __symbol_set_attribute __attribute__ ((weak))
371# endif
372
373/* Return a pointer (void *const *) to the first element of SET. */
374# define symbol_set_first_element(set) ((void *const *) (&__start_##set))
375
376/* Return true iff PTR (a void *const *) has been incremented
377 past the last element in SET. */
378# define symbol_set_end_p(set, ptr) ((ptr) >= (void *const *) &__stop_##set)
379
380# else /* Not ELF: a.out. */
381
382# ifdef HAVE_XCOFF
383/* XCOFF does not support .stabs.
384 The native aix linker will remove the .stab and .stabstr sections
385 The gnu linker will have a fatal error if there is a relocation for
386 symbol in the .stab section. Silently disable these macros. */
387# define text_set_element(set, symbol)
388# define data_set_element(set, symbol)
389# define bss_set_element(set, symbol)
390# else
391# define text_set_element(set, symbol) \
392 asm (".stabs \"" __SYMBOL_PREFIX #set "\",23,0,0," __SYMBOL_PREFIX #symbol)
393# define data_set_element(set, symbol) \
394 asm (".stabs \"" __SYMBOL_PREFIX #set "\",25,0,0," __SYMBOL_PREFIX #symbol)
395# define bss_set_element(set, symbol) ?error Must use initialized data.
396# endif /* XCOFF */
397# define symbol_set_define(set) void *const (set)[1];
398# define symbol_set_declare(set) extern void *const (set)[1];
399
400# define symbol_set_first_element(set) &(set)[1]
401# define symbol_set_end_p(set, ptr) (*(ptr) == 0)
402
403# endif /* ELF. */
404#else
405/* We cannot do anything in generial. */
406# define text_set_element(set, symbol) asm ("")
407# define data_set_element(set, symbol) asm ("")
408# define bss_set_element(set, symbol) asm ("")
409# define symbol_set_define(set) void *const (set)[1];
410# define symbol_set_declare(set) extern void *const (set)[1];
411
412# define symbol_set_first_element(set) &(set)[1]
413# define symbol_set_end_p(set, ptr) (*(ptr) == 0)
414#endif /* Have GNU ld. */
415
416#if DO_VERSIONING
417# define symbol_version(real, name, version) \
418 _symbol_version(real, name, version)
419# define default_symbol_version(real, name, version) \
420 _default_symbol_version(real, name, version)
421# ifdef __ASSEMBLER__
422# ifdef HAVE_ASM_GLOBAL_DOT_NAME
423# define _symbol_version(real, name, version) \
424 .symver real, name##@##version ASM_LINE_SEP \
425 .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##version)
426# define _default_symbol_version(real, name, version) \
427 .symver real, name##@##@##version ASM_LINE_SEP \
428 .symver C_SYMBOL_DOT_NAME(real), C_SYMBOL_DOT_NAME(name##@##@##version)
429# else
430# define _symbol_version(real, name, version) \
431 .symver real, name##@##version
432# define _default_symbol_version(real, name, version) \
433 .symver real, name##@##@##version
434# endif
435# else
436# ifdef HAVE_ASM_GLOBAL_DOT_NAME
437# define _symbol_version(real, name, version) \
438 __asm__ (".symver " #real "," #name "@" #version "\n\t" \
439 ".symver ." #real ",." #name "@" #version)
440# define _default_symbol_version(real, name, version) \
441 __asm__ (".symver " #real "," #name "@@" #version "\n\t" \
442 ".symver ." #real ",." #name "@@" #version)
443# else
444# define _symbol_version(real, name, version) \
445 __asm__ (".symver " #real "," #name "@" #version)
446# define _default_symbol_version(real, name, version) \
447 __asm__ (".symver " #real "," #name "@@" #version)
448# endif
449# endif
450#else
451# define symbol_version(real, name, version)
452# define default_symbol_version(real, name, version) \
453 strong_alias(real, name)
454#endif
455
456#if defined HAVE_VISIBILITY_ATTRIBUTE \
457 && (defined SHARED || defined LIBC_NONSHARED)
458# define attribute_hidden __attribute__ ((visibility ("hidden")))
459#else
460# define attribute_hidden
461#endif
462
463#ifdef HAVE_TLS_MODEL_ATTRIBUTE
464# define attribute_tls_model_ie __attribute__ ((tls_model ("initial-exec")))
465#else
466# define attribute_tls_model_ie
467#endif
468
469#ifdef HAVE_Z_RELRO
470# define attribute_relro __attribute__ ((section (".data.rel.ro")))
471#else
472# define attribute_relro
473#endif
474
475/* Handling on non-exported internal names. We have to do this only
476 for shared code. */
477#ifdef SHARED
478# define INTUSE(name) name##_internal
479# define INTDEF(name) strong_alias (name, name##_internal)
480# define INTVARDEF(name) \
481 _INTVARDEF (name, name##_internal)
482# if defined HAVE_VISIBILITY_ATTRIBUTE
483# define _INTVARDEF(name, aliasname) \
484 extern __typeof (name) aliasname __attribute__ ((alias (#name), \
485 visibility ("hidden")));
486# else
487# define _INTVARDEF(name, aliasname) \
488 extern __typeof (name) aliasname __attribute__ ((alias (#name)));
489# endif
490# define INTDEF2(name, newname) strong_alias (name, newname##_internal)
491# define INTVARDEF2(name, newname) _INTVARDEF (name, newname##_internal)
492#else
493# define INTUSE(name) name
494# define INTDEF(name)
495# define INTVARDEF(name)
496# define INTDEF2(name, newname)
497# define INTVARDEF2(name, newname)
498#endif
499
500/* The following macros are used for PLT bypassing within libc.so
501 (and if needed other libraries similarly).
502 First of all, you need to have the function prototyped somewhere,
503 say in foo/foo.h:
504
505 int foo (int __bar);
506
507 If calls to foo within libc.so should always go to foo defined in libc.so,
508 then in include/foo.h you add:
509
510 libc_hidden_proto (foo)
511
512 line and after the foo function definition:
513
514 int foo (int __bar)
515 {
516 return __bar;
517 }
518 libc_hidden_def (foo)
519
520 or
521
522 int foo (int __bar)
523 {
524 return __bar;
525 }
526 libc_hidden_weak (foo)
527
528 Simularly for global data. If references to foo within libc.so should
529 always go to foo defined in libc.so, then in include/foo.h you add:
530
531 libc_hidden_proto (foo)
532
533 line and after foo's definition:
534
535 int foo = INITIAL_FOO_VALUE;
536 libc_hidden_data_def (foo)
537
538 or
539
540 int foo = INITIAL_FOO_VALUE;
541 libc_hidden_data_weak (foo)
542
543 If foo is normally just an alias (strong or weak) of some other function,
544 you should use the normal strong_alias first, then add libc_hidden_def
545 or libc_hidden_weak:
546
547 int baz (int __bar)
548 {
549 return __bar;
550 }
551 strong_alias (baz, foo)
552 libc_hidden_weak (foo)
553
554 If the function should be internal to multiple objects, say ld.so and
555 libc.so, the best way is to use:
556
557 #if !defined NOT_IN_libc || defined IS_IN_rtld
558 hidden_proto (foo)
559 #endif
560
561 in include/foo.h and the normal macros at all function definitions
562 depending on what DSO they belong to.
563
564 If versioned_symbol macro is used to define foo,
565 libc_hidden_ver macro should be used, as in:
566
567 int __real_foo (int __bar)
568 {
569 return __bar;
570 }
571 versioned_symbol (libc, __real_foo, foo, GLIBC_2_1);
572 libc_hidden_ver (__real_foo, foo) */
573
574#if defined SHARED && defined DO_VERSIONING \
575 && !defined HAVE_BROKEN_ALIAS_ATTRIBUTE && !defined NO_HIDDEN
576# ifndef __ASSEMBLER__
577# if !defined HAVE_VISIBILITY_ATTRIBUTE \
578 || defined HAVE_BROKEN_VISIBILITY_ATTRIBUTE
579# define __hidden_proto_hiddenattr(attrs...)
580# else
581# define __hidden_proto_hiddenattr(attrs...) \
582 __attribute__ ((visibility ("hidden"), ##attrs))
583# endif
584# define hidden_proto(name, attrs...) \
585 __hidden_proto (name, __GI_##name, ##attrs)
586# define __hidden_proto(name, internal, attrs...) \
587 extern __typeof (name) name __asm__ (__hidden_asmname (#internal)) \
588 __hidden_proto_hiddenattr (attrs);
589# define __hidden_asmname(name) \
590 __hidden_asmname1 (__USER_LABEL_PREFIX__, name)
591# define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name)
592# define __hidden_asmname2(prefix, name) #prefix name
593# define __hidden_ver1(local, internal, name) \
594 extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \
595 extern __typeof (name) __EI_##name \
596 __attribute__((alias (__hidden_asmname (#local))))
597# define hidden_ver(local, name) __hidden_ver1(local, __GI_##name, name);
598# define hidden_data_ver(local, name) hidden_ver(local, name)
599# define hidden_def(name) __hidden_ver1(__GI_##name, name, name);
600# define hidden_data_def(name) hidden_def(name)
601# define hidden_weak(name) \
602 __hidden_ver1(__GI_##name, name, name) __attribute__((weak));
603# define hidden_data_weak(name) hidden_weak(name)
604# else
605/* For assembly, we need to do the opposite of what we do in C:
606 in assembly gcc __REDIRECT stuff is not in place, so functions
607 are defined by its normal name and we need to create the
608 __GI_* alias to it, in C __REDIRECT causes the function definition
609 to use __GI_* name and we need to add alias to the real name.
610 There is no reason to use hidden_weak over hidden_def in assembly,
611 but we provide it for consistency with the C usage.
612 hidden_proto doesn't make sense for assembly but the equivalent
613 is to call via the HIDDEN_JUMPTARGET macro instead of JUMPTARGET. */
614# define hidden_def(name) strong_alias (name, __GI_##name)
615# define hidden_weak(name) hidden_def (name)
616# define hidden_ver(local, name) strong_alias (local, __GI_##name)
617# define hidden_data_def(name) strong_data_alias (name, __GI_##name)
618# define hidden_data_weak(name) hidden_data_def (name)
619# define hidden_data_ver(local, name) strong_data_alias (local, __GI_##name)
620# ifdef HAVE_ASM_GLOBAL_DOT_NAME
621# define HIDDEN_JUMPTARGET(name) .__GI_##name
622# else
623# define HIDDEN_JUMPTARGET(name) __GI_##name
624# endif
625# endif
626#else
627# ifndef __ASSEMBLER__
628# define hidden_proto(name, attrs...)
629# else
630# define HIDDEN_JUMPTARGET(name) JUMPTARGET(name)
631# endif /* Not __ASSEMBLER__ */
632# define hidden_weak(name)
633# define hidden_def(name)
634# define hidden_ver(local, name)
635# define hidden_data_weak(name)
636# define hidden_data_def(name)
637# define hidden_data_ver(local, name)
638#endif
639
640#if !defined NOT_IN_libc
641# define libc_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
642# define libc_hidden_def(name) hidden_def (name)
643# define libc_hidden_weak(name) hidden_weak (name)
644# define libc_hidden_ver(local, name) hidden_ver (local, name)
645# define libc_hidden_data_def(name) hidden_data_def (name)
646# define libc_hidden_data_weak(name) hidden_data_weak (name)
647# define libc_hidden_data_ver(local, name) hidden_data_ver (local, name)
648#else
649# define libc_hidden_proto(name, attrs...)
650# define libc_hidden_def(name)
651# define libc_hidden_weak(name)
652# define libc_hidden_ver(local, name)
653# define libc_hidden_data_def(name)
654# define libc_hidden_data_weak(name)
655# define libc_hidden_data_ver(local, name)
656#endif
657
658#if defined NOT_IN_libc && defined IS_IN_rtld
659# define rtld_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
660# define rtld_hidden_def(name) hidden_def (name)
661# define rtld_hidden_weak(name) hidden_weak (name)
662# define rtld_hidden_ver(local, name) hidden_ver (local, name)
663# define rtld_hidden_data_def(name) hidden_data_def (name)
664# define rtld_hidden_data_weak(name) hidden_data_weak (name)
665# define rtld_hidden_data_ver(local, name) hidden_data_ver (local, name)
666#else
667# define rtld_hidden_proto(name, attrs...)
668# define rtld_hidden_def(name)
669# define rtld_hidden_weak(name)
670# define rtld_hidden_ver(local, name)
671# define rtld_hidden_data_def(name)
672# define rtld_hidden_data_weak(name)
673# define rtld_hidden_data_ver(local, name)
674#endif
675
676#if defined NOT_IN_libc && defined IS_IN_libm
677# define libm_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
678# define libm_hidden_def(name) hidden_def (name)
679# define libm_hidden_weak(name) hidden_weak (name)
680# define libm_hidden_ver(local, name) hidden_ver (local, name)
681# define libm_hidden_data_def(name) hidden_data_def (name)
682# define libm_hidden_data_weak(name) hidden_data_weak (name)
683# define libm_hidden_data_ver(local, name) hidden_data_ver (local, name)
684#else
685# define libm_hidden_proto(name, attrs...)
686# define libm_hidden_def(name)
687# define libm_hidden_weak(name)
688# define libm_hidden_ver(local, name)
689# define libm_hidden_data_def(name)
690# define libm_hidden_data_weak(name)
691# define libm_hidden_data_ver(local, name)
692#endif
693
694#if defined NOT_IN_libc && defined IS_IN_libresolv
695# define libresolv_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
696# define libresolv_hidden_def(name) hidden_def (name)
697# define libresolv_hidden_weak(name) hidden_weak (name)
698# define libresolv_hidden_ver(local, name) hidden_ver (local, name)
699# define libresolv_hidden_data_def(name) hidden_data_def (name)
700# define libresolv_hidden_data_weak(name) hidden_data_weak (name)
701# define libresolv_hidden_data_ver(local, name) hidden_data_ver (local, name)
702#else
703# define libresolv_hidden_proto(name, attrs...)
704# define libresolv_hidden_def(name)
705# define libresolv_hidden_weak(name)
706# define libresolv_hidden_ver(local, name)
707# define libresolv_hidden_data_def(name)
708# define libresolv_hidden_data_weak(name)
709# define libresolv_hidden_data_ver(local, name)
710#endif
711
712#if defined NOT_IN_libc && defined IS_IN_libdl
713# define libdl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
714# define libdl_hidden_def(name) hidden_def (name)
715# define libdl_hidden_weak(name) hidden_weak (name)
716# define libdl_hidden_ver(local, name) hidden_ver (local, name)
717# define libdl_hidden_data_def(name) hidden_data_def (name)
718# define libdl_hidden_data_weak(name) hidden_data_weak (name)
719# define libdl_hidden_data_ver(local, name) hidden_data_ver (local, name)
720#else
721# define libdl_hidden_proto(name, attrs...)
722# define libdl_hidden_def(name)
723# define libdl_hidden_weak(name)
724# define libdl_hidden_ver(local, name)
725# define libdl_hidden_data_def(name)
726# define libdl_hidden_data_weak(name)
727# define libdl_hidden_data_ver(local, name)
728#endif
729
730#if defined NOT_IN_libc && defined IS_IN_libnss_files
731# define libnss_files_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
732# define libnss_files_hidden_def(name) hidden_def (name)
733# define libnss_files_hidden_weak(name) hidden_weak (name)
734# define libnss_files_hidden_ver(local, name) hidden_ver (local, name)
735# define libnss_files_hidden_data_def(name) hidden_data_def (name)
736# define libnss_files_hidden_data_weak(name) hidden_data_weak (name)
737# define libnss_files_hidden_data_ver(local, name) hidden_data_ver(local, name)
738#else
739# define libnss_files_hidden_proto(name, attrs...)
740# define libnss_files_hidden_def(name)
741# define libnss_files_hidden_weak(name)
742# define libnss_files_hidden_ver(local, name)
743# define libnss_files_hidden_data_def(name)
744# define libnss_files_hidden_data_weak(name)
745# define libnss_files_hidden_data_ver(local, name)
746#endif
747
748#if defined NOT_IN_libc && defined IS_IN_libnsl
749# define libnsl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
750# define libnsl_hidden_def(name) hidden_def (name)
751# define libnsl_hidden_weak(name) hidden_weak (name)
752# define libnsl_hidden_ver(local, name) hidden_ver (local, name)
753# define libnsl_hidden_data_def(name) hidden_data_def (name)
754# define libnsl_hidden_data_weak(name) hidden_data_weak (name)
755# define libnsl_hidden_data_ver(local, name) hidden_data_ver (local, name)
756#else
757# define libnsl_hidden_proto(name, attrs...)
758# define libnsl_hidden_def(name)
759# define libnsl_hidden_weak(name)
760# define libnsl_hidden_ver(local, name)
761# define libnsl_hidden_data_def(name)
762# define libnsl_hidden_data_weak(name)
763# define libnsl_hidden_data_ver(local, name)
764#endif
765
766#if defined NOT_IN_libc && defined IS_IN_libnss_nisplus
767# define libnss_nisplus_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
768# define libnss_nisplus_hidden_def(name) hidden_def (name)
769# define libnss_nisplus_hidden_weak(name) hidden_weak (name)
770# define libnss_nisplus_hidden_ver(local, name) hidden_ver (local, name)
771# define libnss_nisplus_hidden_data_def(name) hidden_data_def (name)
772# define libnss_nisplus_hidden_data_weak(name) hidden_data_weak (name)
773# define libnss_nisplus_hidden_data_ver(local, name) hidden_data_ver (local, name)
774#else
775# define libnss_nisplus_hidden_proto(name, attrs...)
776# define libnss_nisplus_hidden_def(name)
777# define libnss_nisplus_hidden_weak(name)
778# define libnss_nisplus_hidden_ver(local, name)
779# define libnss_nisplus_hidden_data_def(name)
780# define libnss_nisplus_hidden_data_weak(name)
781# define libnss_nisplus_hidden_data_ver(local, name)
782#endif
783
784#ifdef HAVE_BUILTIN_REDIRECTION
785# define libc_hidden_builtin_proto(name, attrs...) libc_hidden_proto (name, ##attrs)
786# define libc_hidden_builtin_def(name) libc_hidden_def (name)
787# define libc_hidden_builtin_weak(name) libc_hidden_weak (name)
788# define libc_hidden_builtin_ver(local, name) libc_hidden_ver (local, name)
789# ifdef __ASSEMBLER__
790# define HIDDEN_BUILTIN_JUMPTARGET(name) HIDDEN_JUMPTARGET(name)
791# endif
792#else
793# define libc_hidden_builtin_proto(name, attrs...)
794# define libc_hidden_builtin_def(name)
795# define libc_hidden_builtin_weak(name)
796# define libc_hidden_builtin_ver(local, name)
797# ifdef __ASSEMBLER__
798# define HIDDEN_BUILTIN_JUMPTARGET(name) JUMPTARGET(name)
799# endif
800#endif
801
802#if defined NOT_IN_libc && defined IS_IN_libutil
803# define libutil_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
804# define libutil_hidden_def(name) hidden_def (name)
805# define libutil_hidden_weak(name) hidden_weak (name)
806# define libutil_hidden_ver(local, name) hidden_ver (local, name)
807# define libutil_hidden_data_def(name) hidden_data_def (name)
808# define libutil_hidden_data_weak(name) hidden_data_weak (name)
809# define libutil_hidden_data_ver(local, name) hidden_data_ver (local, name)
810#else
811# define libutil_hidden_proto(name, attrs...)
812# define libutil_hidden_def(name)
813# define libutil_hidden_weak(name)
814# define libutil_hidden_ver(local, name)
815# define libutil_hidden_data_def(name)
816# define libutil_hidden_data_weak(name)
817# define libutil_hidden_data_ver(local, name)
818#endif
819
820/* Get some dirty hacks. */
821#include <symbol-hacks.h>
822
823/* Move compatibility symbols out of the way by placing them all in a
824 special section. */
825#ifndef __ASSEMBLER__
826# define attribute_compat_text_section \
827 __attribute__ ((section (".text.compat")))
828# define attribute_compat_data_section \
829 __attribute__ ((section (".data.compat")))
830#else
831# define compat_text_section .section ".text.compat", "ax";
832# define compat_data_section .section ".data.compat", "aw";
833#endif
834
835#endif /* libc-symbols.h */
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