]> git.ipfire.org Git - thirdparty/gcc.git/blame - libgcc/crtstuff.c
2019-06-13 Richard Biener <rguenther@suse.de>
[thirdparty/gcc.git] / libgcc / crtstuff.c
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9d13f5c4 1/* Specialized bits of code needed to support construction and
2 destruction of file-scope objects in C++ code.
fbd26352 3 Copyright (C) 1991-2019 Free Software Foundation, Inc.
31dcf09a 4 Contributed by Ron Guilmette (rfg@monkeys.com).
9d13f5c4 5
f12b58b3 6This file is part of GCC.
9d13f5c4 7
f12b58b3 8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
6bc9506f 10Software Foundation; either version 3, or (at your option) any later
f12b58b3 11version.
9d13f5c4 12
f12b58b3 13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
9d13f5c4 17
6bc9506f 18Under Section 7 of GPL version 3, you are granted additional
19permissions described in the GCC Runtime Library Exception, version
203.1, as published by the Free Software Foundation.
21
22You should have received a copy of the GNU General Public License and
23a copy of the GCC Runtime Library Exception along with this program;
24see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25<http://www.gnu.org/licenses/>. */
9d13f5c4 26
23573244 27/* This file is a bit like libgcc2.c in that it is compiled
9d13f5c4 28 multiple times and yields multiple .o files.
29
30 This file is useful on target machines where the object file format
31 supports multiple "user-defined" sections (e.g. COFF, ELF, ROSE). On
32 such systems, this file allows us to avoid running collect (or any
33 other such slow and painful kludge). Additionally, if the target
34 system supports a .init section, this file allows us to support the
35 linking of C++ code with a non-C++ main program.
36
37 Note that if INIT_SECTION_ASM_OP is defined in the tm.h file, then
38 this file *will* make use of the .init section. If that symbol is
39 not defined however, then the .init section will not be used.
40
5dd605c6 41 Currently, only ELF and COFF are supported. It is likely however that
42 ROSE could also be supported, if someone was willing to do the work to
43 make whatever (small?) adaptations are needed. (Some work may be
44 needed on the ROSE assembler and linker also.)
9d13f5c4 45
46 This file must be compiled with gcc. */
47
fece7655 48/* Target machine header files require this define. */
49#define IN_LIBGCC2
50
dd41a27b 51/* FIXME: Including auto-host is incorrect, but until we have
52 identified the set of defines that need to go into auto-target.h,
53 this will have to do. */
54#include "auto-host.h"
e3108d46 55#undef caddr_t
9ed5ef25 56#undef pid_t
57#undef rlim_t
58#undef ssize_t
9ed5ef25 59#undef vfork
d826737c 60#include "tconfig.h"
069631e1 61#include "tsystem.h"
805e22b2 62#include "coretypes.h"
63#include "tm.h"
022a2799 64#include "libgcc_tm.h"
df4b504c 65#include "unwind-dw2-fde.h"
9d13f5c4 66
e1ff7102 67#ifndef FORCE_CODE_SECTION_ALIGN
68# define FORCE_CODE_SECTION_ALIGN
69#endif
70
a815e00c 71#ifndef CRT_CALL_STATIC_FUNCTION
e1ff7102 72# define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
73static void __attribute__((__used__)) \
74call_ ## FUNC (void) \
75{ \
76 asm (SECTION_OP); \
77 FUNC (); \
78 FORCE_CODE_SECTION_ALIGN \
325b8c3c 79 asm (__LIBGCC_TEXT_SECTION_ASM_OP__); \
e1ff7102 80}
a815e00c 81#endif
82
463553db 83#if defined(TARGET_DL_ITERATE_PHDR) && \
9834d450 84 (defined(__DragonFly__) || defined(__FreeBSD__) || defined(__NetBSD__))
463553db 85#define BSD_DL_ITERATE_PHDR_AVAILABLE
86#endif
87
fb4bac8b 88#if defined(OBJECT_FORMAT_ELF) \
89 && !defined(OBJECT_FORMAT_FLAT) \
90 && defined(HAVE_LD_EH_FRAME_HDR) \
91 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
463553db 92 && defined(BSD_DL_ITERATE_PHDR_AVAILABLE)
fb4bac8b 93#include <link.h>
94# define USE_PT_GNU_EH_FRAME
95#endif
96
bdd793b2 97#if defined(OBJECT_FORMAT_ELF) \
98 && !defined(OBJECT_FORMAT_FLAT) \
99 && defined(HAVE_LD_EH_FRAME_HDR) && defined(TARGET_DL_ITERATE_PHDR) \
100 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
101 && defined(__sun__) && defined(__svr4__)
102#include <link.h>
103# define USE_PT_GNU_EH_FRAME
104#endif
105
f8200b2a 106#if defined(OBJECT_FORMAT_ELF) \
107 && !defined(OBJECT_FORMAT_FLAT) \
108 && defined(HAVE_LD_EH_FRAME_HDR) \
3cfa3aba 109 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
0d6378a9 110 && defined(__GLIBC__) && __GLIBC__ >= 2
111#include <link.h>
b0c091c8 112/* uClibc pretends to be glibc 2.2 and DT_CONFIG is defined in its link.h.
113 But it doesn't use PT_GNU_EH_FRAME ELF segment currently. */
114# if !defined(__UCLIBC__) \
115 && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
0d6378a9 116 || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
117# define USE_PT_GNU_EH_FRAME
118# endif
119#endif
93547515 120
121#if defined(OBJECT_FORMAT_ELF) \
122 && !defined(OBJECT_FORMAT_FLAT) \
123 && defined(HAVE_LD_EH_FRAME_HDR) \
124 && !defined(CRTSTUFFT_O) \
125 && defined(inhibit_libc) \
126 && (defined(__GLIBC__) || defined(__gnu_linux__) || defined(__GNU__))
127/* On systems using glibc, an inhibit_libc build of libgcc is only
128 part of a bootstrap process. Build the same crt*.o as would be
129 built with headers present, so that it is not necessary to build
130 glibc more than once for the bootstrap to converge. */
131# define USE_PT_GNU_EH_FRAME
132#endif
133
d0eb4a95 134#ifdef USE_EH_FRAME_REGISTRY_ALWAYS
135# ifndef __LIBGCC_EH_FRAME_SECTION_NAME__
136# error "Can't use explicit exception-frame-registration without __LIBGCC_EH_FRAME_SECTION_NAME__"
137# endif
138#endif
139#if defined(__LIBGCC_EH_FRAME_SECTION_NAME__) && (!defined(USE_PT_GNU_EH_FRAME) || defined(USE_EH_FRAME_REGISTRY_ALWAYS))
0d6378a9 140# define USE_EH_FRAME_REGISTRY
141#endif
325b8c3c 142#if defined(__LIBGCC_EH_FRAME_SECTION_NAME__) \
143 && __LIBGCC_EH_TABLES_CAN_BE_READ_ONLY__
d5720b0c 144# define EH_FRAME_SECTION_CONST const
145#else
146# define EH_FRAME_SECTION_CONST
147#endif
0d6378a9 148
f9e6c0d4 149#if !defined(DTOR_LIST_END) && defined(OBJECT_FORMAT_ELF) \
150 && defined(HAVE_GAS_HIDDEN) && !defined(FINI_ARRAY_SECTION_ASM_OP)
151# define HIDDEN_DTOR_LIST_END
152#endif
153
2d171408 154#if !defined(USE_TM_CLONE_REGISTRY) && defined(OBJECT_FORMAT_ELF)
155# define USE_TM_CLONE_REGISTRY 1
156#endif
157
ee055d40 158/* We do not want to add the weak attribute to the declarations of these
df4b504c 159 routines in unwind-dw2-fde.h because that will cause the definition of
160 these symbols to be weak as well.
ee055d40 161
162 This exposes a core issue, how to handle creating weak references vs
163 how to create weak definitions. Either we have to have the definition
164 of TARGET_WEAK_ATTRIBUTE be conditional in the shared header files or
165 have a second declaration if we want a function's references to be weak,
166 but not its definition.
167
168 Making TARGET_WEAK_ATTRIBUTE conditional seems like a good solution until
0c6d8c36 169 one thinks about scaling to larger problems -- i.e., the condition under
ee055d40 170 which TARGET_WEAK_ATTRIBUTE is active will eventually get far too
171 complicated.
172
173 So, we take an approach similar to #pragma weak -- we have a second
174 declaration for functions that we want to have weak references.
175
176 Neither way is particularly good. */
48e1416a 177
ee055d40 178/* References to __register_frame_info and __deregister_frame_info should
179 be weak in this file if at all possible. */
49856054 180extern void __register_frame_info (const void *, struct object *)
ee055d40 181 TARGET_ATTRIBUTE_WEAK;
49856054 182extern void __register_frame_info_bases (const void *, struct object *,
f6338f42 183 void *, void *)
184 TARGET_ATTRIBUTE_WEAK;
49856054 185extern void *__deregister_frame_info (const void *)
ee055d40 186 TARGET_ATTRIBUTE_WEAK;
49856054 187extern void *__deregister_frame_info_bases (const void *)
ce32d35f 188 TARGET_ATTRIBUTE_WEAK;
db0f4f32 189extern void __do_global_ctors_1 (void);
ee055d40 190
2d171408 191/* Likewise for transactional memory clone tables. */
192extern void _ITM_registerTMCloneTable (void *, size_t) TARGET_ATTRIBUTE_WEAK;
193extern void _ITM_deregisterTMCloneTable (void *) TARGET_ATTRIBUTE_WEAK;
194
b7c87ff2 195#ifdef OBJECT_FORMAT_ELF
196
197/* Declare a pointer to void function type. */
198typedef void (*func_ptr) (void);
199#define STATIC static
200
201#else /* OBJECT_FORMAT_ELF */
202
9d13f5c4 203#include "gbl-ctors.h"
204
b7c87ff2 205#define STATIC
206
207#endif /* OBJECT_FORMAT_ELF */
9d13f5c4 208
209#ifdef CRT_BEGIN
210
f313c0e1 211/* NOTE: In order to be able to support SVR4 shared libraries, we arrange
212 to have one set of symbols { __CTOR_LIST__, __DTOR_LIST__, __CTOR_END__,
213 __DTOR_END__ } per root executable and also one set of these symbols
214 per shared library. So in any given whole process image, we may have
215 multiple definitions of each of these symbols. In order to prevent
216 these definitions from conflicting with one another, and in order to
217 ensure that the proper lists are used for the initialization/finalization
218 of each individual shared library (respectively), we give these symbols
219 only internal (i.e. `static') linkage, and we also make it a point to
220 refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__
221 symbol in crtbegin.o, where they are defined. */
222
ef1da805 223/* No need for .ctors/.dtors section if linker can place them in
224 .init_array/.fini_array section. */
225#ifndef USE_INITFINI_ARRAY
f313c0e1 226/* The -1 is a flag to __do_global_[cd]tors indicating that this table
227 does not start with a count of elements. */
228#ifdef CTOR_LIST_BEGIN
229CTOR_LIST_BEGIN;
325b8c3c 230#elif defined(__LIBGCC_CTORS_SECTION_ASM_OP__)
f313c0e1 231/* Hack: force cc1 to switch to .data section early, so that assembling
232 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
796535a3 233static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
325b8c3c 234asm (__LIBGCC_CTORS_SECTION_ASM_OP__);
f313c0e1 235STATIC func_ptr __CTOR_LIST__[1]
796535a3 236 __attribute__ ((__used__, aligned(sizeof(func_ptr))))
f313c0e1 237 = { (func_ptr) (-1) };
238#else
239STATIC func_ptr __CTOR_LIST__[1]
796535a3 240 __attribute__ ((__used__, section(".ctors"), aligned(sizeof(func_ptr))))
f313c0e1 241 = { (func_ptr) (-1) };
242#endif /* __CTOR_LIST__ alternatives */
243
244#ifdef DTOR_LIST_BEGIN
245DTOR_LIST_BEGIN;
325b8c3c 246#elif defined(__LIBGCC_DTORS_SECTION_ASM_OP__)
247asm (__LIBGCC_DTORS_SECTION_ASM_OP__);
f313c0e1 248STATIC func_ptr __DTOR_LIST__[1]
249 __attribute__ ((aligned(sizeof(func_ptr))))
250 = { (func_ptr) (-1) };
251#else
252STATIC func_ptr __DTOR_LIST__[1]
253 __attribute__((section(".dtors"), aligned(sizeof(func_ptr))))
254 = { (func_ptr) (-1) };
255#endif /* __DTOR_LIST__ alternatives */
ef1da805 256#endif /* USE_INITFINI_ARRAY */
f313c0e1 257
fabbeb08 258#ifdef USE_EH_FRAME_REGISTRY
f313c0e1 259/* Stick a label at the beginning of the frame unwind info so we can register
260 and deregister it with the exception handling library code. */
d5720b0c 261STATIC EH_FRAME_SECTION_CONST char __EH_FRAME_BEGIN__[]
325b8c3c 262 __attribute__((section(__LIBGCC_EH_FRAME_SECTION_NAME__), aligned(4)))
f313c0e1 263 = { };
fabbeb08 264#endif /* USE_EH_FRAME_REGISTRY */
f313c0e1 265
2d171408 266#if USE_TM_CLONE_REGISTRY
267STATIC func_ptr __TMC_LIST__[]
d9ca835b 268 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void*))))
2d171408 269 = { };
d9ca835b 270# ifdef HAVE_GAS_HIDDEN
2d171408 271extern func_ptr __TMC_END__[] __attribute__((__visibility__ ("hidden")));
d9ca835b 272# endif
273
274static inline void
275deregister_tm_clones (void)
276{
277 void (*fn) (void *);
278
279#ifdef HAVE_GAS_HIDDEN
7dbfd9e6 280 func_ptr *end = __TMC_END__;
281 // Do not optimize the comparison to false.
282 __asm ("" : "+g" (end));
283 if (__TMC_LIST__ == end)
d9ca835b 284 return;
285#else
286 if (__TMC_LIST__[0] == NULL)
287 return;
288#endif
289
290 fn = _ITM_deregisterTMCloneTable;
291 __asm ("" : "+r" (fn));
292 if (fn)
293 fn (__TMC_LIST__);
294}
295
296static inline void
297register_tm_clones (void)
298{
299 void (*fn) (void *, size_t);
300 size_t size;
301
302#ifdef HAVE_GAS_HIDDEN
7dbfd9e6 303 func_ptr *end = __TMC_END__;
304 // Do not optimize the comparison to false.
305 __asm ("" : "+g" (end));
306 size = (end - __TMC_LIST__) / 2;
d9ca835b 307#else
308 for (size = 0; __TMC_LIST__[size * 2] != NULL; size++)
309 continue;
310#endif
311 if (size == 0)
312 return;
313
314 fn = _ITM_registerTMCloneTable;
315 __asm ("" : "+r" (fn));
316 if (fn)
317 fn (__TMC_LIST__, size);
318}
2d171408 319#endif /* USE_TM_CLONE_REGISTRY */
320
325b8c3c 321#if defined(__LIBGCC_INIT_SECTION_ASM_OP__) \
322 || defined(__LIBGCC_INIT_ARRAY_SECTION_ASM_OP__)
584907e7 323
b7c87ff2 324#ifdef OBJECT_FORMAT_ELF
325
39b6af4b 326/* Declare the __dso_handle variable. It should have a unique value
5be729c9 327 in every shared-object; in a main program its value is zero. The
328 object should in any case be protected. This means the instance
329 in one DSO or the main program is not used in another object. The
330 dynamic linker takes care of this. */
331
91e8ab5c 332#ifdef TARGET_LIBGCC_SDATA_SECTION
333extern void *__dso_handle __attribute__ ((__section__ (TARGET_LIBGCC_SDATA_SECTION)));
334#endif
5be729c9 335#ifdef HAVE_GAS_HIDDEN
b4cf9ec1 336extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
5be729c9 337#endif
39b6af4b 338#ifdef CRTSTUFFS_O
339void *__dso_handle = &__dso_handle;
340#else
341void *__dso_handle = 0;
342#endif
343
344/* The __cxa_finalize function may not be available so we use only a
345 weak declaration. */
346extern void __cxa_finalize (void *) TARGET_ATTRIBUTE_WEAK;
347
b7c87ff2 348/* Run all the global destructors on exit from the program. */
48e1416a 349
b7c87ff2 350/* Some systems place the number of pointers in the first word of the
351 table. On SVR4 however, that word is -1. In all cases, the table is
352 null-terminated. On SVR4, we start from the beginning of the list and
353 invoke each per-compilation-unit destructor routine in order
354 until we find that null.
355
356 Note that this function MUST be static. There will be one of these
357 functions in each root executable and one in each shared library, but
358 although they all have the same code, each one is unique in that it
359 refers to one particular associated `__DTOR_LIST__' which belongs to the
113f9ca7 360 same particular root executable or shared library file.
361
362 On some systems, this routine is run more than once from the .fini,
363 when exit is called recursively, so we arrange to remember where in
364 the list we left off processing, and we resume at that point,
365 should we be re-invoked. */
b7c87ff2 366
e1ff7102 367static void __attribute__((used))
aedb00bf 368__do_global_dtors_aux (void)
b7c87ff2 369{
d24bc145 370 static _Bool completed;
dade0711 371
f6338f42 372 if (__builtin_expect (completed, 0))
dade0711 373 return;
374
f4513b3d 375#ifdef CRTSTUFFS_O
376 if (__cxa_finalize)
39b6af4b 377 __cxa_finalize (__dso_handle);
f4513b3d 378#endif
39b6af4b 379
d24bc145 380#ifdef FINI_ARRAY_SECTION_ASM_OP
381 /* If we are using .fini_array then destructors will be run via that
382 mechanism. */
f9e6c0d4 383#elif defined(HIDDEN_DTOR_LIST_END)
384 {
385 /* Safer version that makes sure only .dtors function pointers are
386 called even if the static variable is maliciously changed. */
387 extern func_ptr __DTOR_END__[] __attribute__((visibility ("hidden")));
388 static size_t dtor_idx;
389 const size_t max_idx = __DTOR_END__ - __DTOR_LIST__ - 1;
06f29f53 390 func_ptr *dtor_list;
f9e6c0d4 391
06f29f53 392 __asm ("" : "=g" (dtor_list) : "0" (__DTOR_LIST__));
f9e6c0d4 393 while (dtor_idx < max_idx)
06f29f53 394 dtor_list[++dtor_idx] ();
f9e6c0d4 395 }
d24bc145 396#else /* !defined (FINI_ARRAY_SECTION_ASM_OP) */
f9e6c0d4 397 {
398 static func_ptr *p = __DTOR_LIST__ + 1;
399 func_ptr f;
400
401 while ((f = *p))
402 {
403 p++;
404 f ();
405 }
406 }
d24bc145 407#endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
d757b8c9 408
2d171408 409#if USE_TM_CLONE_REGISTRY
d9ca835b 410 deregister_tm_clones ();
2d171408 411#endif /* USE_TM_CLONE_REGISTRY */
412
0d6378a9 413#ifdef USE_EH_FRAME_REGISTRY
6fa2a5a8 414#ifdef CRT_GET_RFIB_DATA
ce32d35f 415 /* If we used the new __register_frame_info_bases interface,
416 make sure that we deregister from the same place. */
417 if (__deregister_frame_info_bases)
418 __deregister_frame_info_bases (__EH_FRAME_BEGIN__);
419#else
ee055d40 420 if (__deregister_frame_info)
421 __deregister_frame_info (__EH_FRAME_BEGIN__);
d757b8c9 422#endif
ce32d35f 423#endif
424
dade0711 425 completed = 1;
b7c87ff2 426}
427
428/* Stick a call to __do_global_dtors_aux into the .fini section. */
d24bc145 429#ifdef FINI_SECTION_ASM_OP
e1ff7102 430CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux)
a9a8ff12 431#elif defined (FINI_ARRAY_SECTION_ASM_OP)
d24bc145 432static func_ptr __do_global_dtors_aux_fini_array_entry[]
a41e0f2d 433 __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr))))
d24bc145 434 = { __do_global_dtors_aux };
a9a8ff12 435#else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */
436static void __attribute__((used))
437__do_global_dtors_aux_1 (void)
438{
439 atexit (__do_global_dtors_aux);
440}
325b8c3c 441CRT_CALL_STATIC_FUNCTION (__LIBGCC_INIT_SECTION_ASM_OP__,
442 __do_global_dtors_aux_1)
a9a8ff12 443#endif
b7c87ff2 444
2d171408 445#if defined(USE_EH_FRAME_REGISTRY) \
2d171408 446 || defined(USE_TM_CLONE_REGISTRY)
c4fa4c4d 447/* Stick a call to __register_frame_info into the .init section. For some
448 reason calls with no arguments work more reliably in .init, so stick the
449 call in another function. */
d757b8c9 450
e1ff7102 451static void __attribute__((used))
aedb00bf 452frame_dummy (void)
d757b8c9 453{
0d6378a9 454#ifdef USE_EH_FRAME_REGISTRY
ad87de1e 455 static struct object object;
6fa2a5a8 456#ifdef CRT_GET_RFIB_DATA
f6338f42 457 void *tbase, *dbase;
f6338f42 458 tbase = 0;
f6338f42 459 CRT_GET_RFIB_DATA (dbase);
f6338f42 460 if (__register_frame_info_bases)
461 __register_frame_info_bases (__EH_FRAME_BEGIN__, &object, tbase, dbase);
462#else
ee055d40 463 if (__register_frame_info)
464 __register_frame_info (__EH_FRAME_BEGIN__, &object);
6fa2a5a8 465#endif /* CRT_GET_RFIB_DATA */
71fcebb2 466#endif /* USE_EH_FRAME_REGISTRY */
2d171408 467
2d171408 468#if USE_TM_CLONE_REGISTRY
d9ca835b 469 register_tm_clones ();
2d171408 470#endif /* USE_TM_CLONE_REGISTRY */
d757b8c9 471}
472
325b8c3c 473#ifdef __LIBGCC_INIT_SECTION_ASM_OP__
474CRT_CALL_STATIC_FUNCTION (__LIBGCC_INIT_SECTION_ASM_OP__, frame_dummy)
475#else /* defined(__LIBGCC_INIT_SECTION_ASM_OP__) */
d24bc145 476static func_ptr __frame_dummy_init_array_entry[]
a41e0f2d 477 __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr))))
d24bc145 478 = { frame_dummy };
325b8c3c 479#endif /* !defined(__LIBGCC_INIT_SECTION_ASM_OP__) */
bc6b11a7 480#endif /* USE_EH_FRAME_REGISTRY || USE_TM_CLONE_REGISTRY */
d757b8c9 481
b7c87ff2 482#else /* OBJECT_FORMAT_ELF */
483
b13ae905 484/* The function __do_global_ctors_aux is compiled twice (once in crtbegin.o
d8fa92ab 485 and once in crtend.o). It must be declared static to avoid a link
b13ae905 486 error. Here, we define __do_global_ctors as an externally callable
487 function. It is externally callable so that __main can invoke it when
488 INVOKE__main is defined. This has the additional effect of forcing cc1
489 to switch to the .text section. */
a92771b8 490
205b5771 491static void __do_global_ctors_aux (void);
aedb00bf 492void
493__do_global_ctors (void)
84b64a19 494{
584907e7 495#ifdef INVOKE__main
496 /* If __main won't actually call __do_global_ctors then it doesn't matter
497 what's inside the function. The inside of __do_global_ctors_aux is
498 called automatically in that case. And the Alliant fx2800 linker
499 crashes on this reference. So prevent the crash. */
84b64a19 500 __do_global_ctors_aux ();
501#endif
502}
9d13f5c4 503
325b8c3c 504asm (__LIBGCC_INIT_SECTION_ASM_OP__); /* cc1 doesn't know that we are switching! */
9d13f5c4 505
506/* A routine to invoke all of the global constructors upon entry to the
507 program. We put this into the .init section (for systems that have
508 such a thing) so that we can properly perform the construction of
1e625a2e 509 file-scope static-storage C++ objects within shared libraries. */
9d13f5c4 510
e1ff7102 511static void __attribute__((used))
aedb00bf 512__do_global_ctors_aux (void) /* prologue goes in .init section */
9d13f5c4 513{
e1ff7102 514 FORCE_CODE_SECTION_ALIGN /* explicit align before switch to .text */
325b8c3c 515 asm (__LIBGCC_TEXT_SECTION_ASM_OP__); /* don't put epilogue and body in .init */
9d13f5c4 516 DO_GLOBAL_CTORS_BODY;
75d3a87b 517 atexit (__do_global_dtors);
9d13f5c4 518}
519
b7c87ff2 520#endif /* OBJECT_FORMAT_ELF */
8313a782 521
325b8c3c 522#elif defined(HAS_INIT_SECTION) /* ! __LIBGCC_INIT_SECTION_ASM_OP__ */
8313a782 523
eb7ed20c 524extern void __do_global_dtors (void);
525
8313a782 526/* This case is used by the Irix 6 port, which supports named sections but
527 not an SVR4-style .fini section. __do_global_dtors can be non-static
d757b8c9 528 in this case because we protect it with -hidden_symbol. */
529
8313a782 530void
aedb00bf 531__do_global_dtors (void)
8313a782 532{
f6338f42 533 func_ptr *p, f;
534 for (p = __DTOR_LIST__ + 1; (f = *p); p++)
535 f ();
d757b8c9 536
2d171408 537#if USE_TM_CLONE_REGISTRY
d9ca835b 538 deregister_tm_clones ();
2d171408 539#endif /* USE_TM_CLONE_REGISTRY */
540
0d6378a9 541#ifdef USE_EH_FRAME_REGISTRY
ee055d40 542 if (__deregister_frame_info)
543 __deregister_frame_info (__EH_FRAME_BEGIN__);
d757b8c9 544#endif
8313a782 545}
72ac783d 546
2d171408 547#if defined(USE_EH_FRAME_REGISTRY) \
2d171408 548 || defined(USE_TM_CLONE_REGISTRY)
584907e7 549/* A helper function for __do_global_ctors, which is in crtend.o. Here
550 in crtbegin.o, we can reference a couple of symbols not visible there.
551 Plus, since we're before libgcc.a, we have no problems referencing
552 functions from there. */
72ac783d 553void
584907e7 554__do_global_ctors_1(void)
72ac783d 555{
0d6378a9 556#ifdef USE_EH_FRAME_REGISTRY
72ac783d 557 static struct object object;
ee055d40 558 if (__register_frame_info)
559 __register_frame_info (__EH_FRAME_BEGIN__, &object);
b13ae905 560#endif
2d171408 561
2d171408 562#if USE_TM_CLONE_REGISTRY
d9ca835b 563 register_tm_clones ();
2d171408 564#endif /* USE_TM_CLONE_REGISTRY */
f313c0e1 565}
bc6b11a7 566#endif /* USE_EH_FRAME_REGISTRY || USE_TM_CLONE_REGISTRY */
2cee371f 567
325b8c3c 568#else /* ! __LIBGCC_INIT_SECTION_ASM_OP__ && ! HAS_INIT_SECTION */
584907e7 569#error "What are you doing with crtstuff.c, then?"
570#endif
571
572#elif defined(CRT_END) /* ! CRT_BEGIN */
573
ef1da805 574/* No need for .ctors/.dtors section if linker can place them in
575 .init_array/.fini_array section. */
576#ifndef USE_INITFINI_ARRAY
584907e7 577/* Put a word containing zero at the end of each of our two lists of function
578 addresses. Note that the words defined here go into the .ctors and .dtors
579 sections of the crtend.o file, and since that file is always linked in
580 last, these words naturally end up at the very ends of the two lists
581 contained in these two sections. */
582
583#ifdef CTOR_LIST_END
584CTOR_LIST_END;
325b8c3c 585#elif defined(__LIBGCC_CTORS_SECTION_ASM_OP__)
584907e7 586/* Hack: force cc1 to switch to .data section early, so that assembling
587 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
796535a3 588static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
325b8c3c 589asm (__LIBGCC_CTORS_SECTION_ASM_OP__);
584907e7 590STATIC func_ptr __CTOR_END__[1]
591 __attribute__((aligned(sizeof(func_ptr))))
592 = { (func_ptr) 0 };
593#else
594STATIC func_ptr __CTOR_END__[1]
595 __attribute__((section(".ctors"), aligned(sizeof(func_ptr))))
596 = { (func_ptr) 0 };
597#endif
598
599#ifdef DTOR_LIST_END
600DTOR_LIST_END;
f9e6c0d4 601#elif defined(HIDDEN_DTOR_LIST_END)
325b8c3c 602#ifdef __LIBGCC_DTORS_SECTION_ASM_OP__
603asm (__LIBGCC_DTORS_SECTION_ASM_OP__);
f9e6c0d4 604#endif
605func_ptr __DTOR_END__[1]
bc200246 606 __attribute__ ((used,
325b8c3c 607#ifndef __LIBGCC_DTORS_SECTION_ASM_OP__
f9e6c0d4 608 section(".dtors"),
609#endif
610 aligned(sizeof(func_ptr)), visibility ("hidden")))
611 = { (func_ptr) 0 };
325b8c3c 612#elif defined(__LIBGCC_DTORS_SECTION_ASM_OP__)
613asm (__LIBGCC_DTORS_SECTION_ASM_OP__);
584907e7 614STATIC func_ptr __DTOR_END__[1]
bc200246 615 __attribute__ ((used, aligned(sizeof(func_ptr))))
584907e7 616 = { (func_ptr) 0 };
617#else
618STATIC func_ptr __DTOR_END__[1]
bc200246 619 __attribute__((used, section(".dtors"), aligned(sizeof(func_ptr))))
584907e7 620 = { (func_ptr) 0 };
621#endif
ef1da805 622#endif /* USE_INITFINI_ARRAY */
9d13f5c4 623
325b8c3c 624#ifdef __LIBGCC_EH_FRAME_SECTION_NAME__
584907e7 625/* Terminate the frame unwind info section with a 4byte 0 as a sentinel;
626 this would be the 'length' field in a real FDE. */
743a6f47 627# if __INT_MAX__ == 2147483647
628typedef int int32;
629# elif __LONG_MAX__ == 2147483647
630typedef long int32;
631# elif __SHRT_MAX__ == 2147483647
632typedef short int32;
633# else
634# error "Missing a 4 byte integer"
635# endif
636STATIC EH_FRAME_SECTION_CONST int32 __FRAME_END__[]
325b8c3c 637 __attribute__ ((used, section(__LIBGCC_EH_FRAME_SECTION_NAME__),
743a6f47 638 aligned(sizeof(int32))))
584907e7 639 = { 0 };
325b8c3c 640#endif /* __LIBGCC_EH_FRAME_SECTION_NAME__ */
584907e7 641
2d171408 642#if USE_TM_CLONE_REGISTRY
d9ca835b 643# ifndef HAVE_GAS_HIDDEN
644static
645# endif
2d171408 646func_ptr __TMC_END__[]
d9ca835b 647 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void *))))
648# ifdef HAVE_GAS_HIDDEN
649 __attribute__((__visibility__ ("hidden"))) = { };
650# else
651 = { 0, 0 };
652# endif
2d171408 653#endif /* USE_TM_CLONE_REGISTRY */
654
325b8c3c 655#ifdef __LIBGCC_INIT_ARRAY_SECTION_ASM_OP__
d24bc145 656
657/* If we are using .init_array, there is nothing to do. */
658
325b8c3c 659#elif defined(__LIBGCC_INIT_SECTION_ASM_OP__)
9d13f5c4 660
b7c87ff2 661#ifdef OBJECT_FORMAT_ELF
e1ff7102 662static void __attribute__((used))
aedb00bf 663__do_global_ctors_aux (void)
b7c87ff2 664{
665 func_ptr *p;
666 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
667 (*p) ();
668}
669
670/* Stick a call to __do_global_ctors_aux into the .init section. */
325b8c3c 671CRT_CALL_STATIC_FUNCTION (__LIBGCC_INIT_SECTION_ASM_OP__, __do_global_ctors_aux)
b7c87ff2 672#else /* OBJECT_FORMAT_ELF */
673
674/* Stick the real initialization code, followed by a normal sort of
675 function epilogue at the very end of the .init section for this
676 entire root executable file or for this entire shared library file.
677
678 Note that we use some tricks here to get *just* the body and just
679 a function epilogue (but no function prologue) into the .init
c3418f42 680 section of the crtend.o file. Specifically, we switch to the .text
b7c87ff2 681 section, start to define a function, and then we switch to the .init
682 section just before the body code.
683
684 Earlier on, we put the corresponding function prologue into the .init
685 section of the crtbegin.o file (which will be linked in first).
686
687 Note that we want to invoke all constructors for C++ file-scope static-
688 storage objects AFTER any other possible initialization actions which
689 may be performed by the code in the .init section contributions made by
690 other libraries, etc. That's because those other initializations may
691 include setup operations for very primitive things (e.g. initializing
692 the state of the floating-point coprocessor, etc.) which should be done
a92771b8 693 before we start to execute any of the user's code. */
9d13f5c4 694
695static void
aedb00bf 696__do_global_ctors_aux (void) /* prologue goes in .text section */
9d13f5c4 697{
325b8c3c 698 asm (__LIBGCC_INIT_SECTION_ASM_OP__);
9d13f5c4 699 DO_GLOBAL_CTORS_BODY;
75d3a87b 700 atexit (__do_global_dtors);
997d68fe 701} /* epilogue and body go in .init section */
702
e1ff7102 703FORCE_CODE_SECTION_ALIGN
325b8c3c 704asm (__LIBGCC_TEXT_SECTION_ASM_OP__);
9d13f5c4 705
b7c87ff2 706#endif /* OBJECT_FORMAT_ELF */
707
325b8c3c 708#elif defined(HAS_INIT_SECTION) /* ! __LIBGCC_INIT_SECTION_ASM_OP__ */
8313a782 709
eb7ed20c 710extern void __do_global_ctors (void);
711
8313a782 712/* This case is used by the Irix 6 port, which supports named sections but
713 not an SVR4-style .init section. __do_global_ctors can be non-static
d757b8c9 714 in this case because we protect it with -hidden_symbol. */
8313a782 715void
aedb00bf 716__do_global_ctors (void)
8313a782 717{
718 func_ptr *p;
2d171408 719#if defined(USE_EH_FRAME_REGISTRY) \
2d171408 720 || defined(USE_TM_CLONE_REGISTRY)
584907e7 721 __do_global_ctors_1();
d757b8c9 722#endif
8313a782 723 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
724 (*p) ();
725}
b7c87ff2 726
325b8c3c 727#else /* ! __LIBGCC_INIT_SECTION_ASM_OP__ && ! HAS_INIT_SECTION */
584907e7 728#error "What are you doing with crtstuff.c, then?"
b13ae905 729#endif
9d13f5c4 730
584907e7 731#else /* ! CRT_BEGIN && ! CRT_END */
732#error "One of CRT_BEGIN or CRT_END must be defined."
b13ae905 733#endif