/cp
[official-gcc.git] / libgcc / crtstuff.c
blob0beda5e571649d973dea8995641e7dca8a85e3b2
1 /* Specialized bits of code needed to support construction and
2 destruction of file-scope objects in C++ code.
3 Copyright (C) 1991-2013 Free Software Foundation, Inc.
4 Contributed by Ron Guilmette (rfg@monkeys.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 Under Section 7 of GPL version 3, you are granted additional
19 permissions described in the GCC Runtime Library Exception, version
20 3.1, as published by the Free Software Foundation.
22 You should have received a copy of the GNU General Public License and
23 a copy of the GCC Runtime Library Exception along with this program;
24 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25 <http://www.gnu.org/licenses/>. */
27 /* This file is a bit like libgcc2.c in that it is compiled
28 multiple times and yields multiple .o files.
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.
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.
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.)
46 This file must be compiled with gcc. */
48 /* Target machine header files require this define. */
49 #define IN_LIBGCC2
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"
55 #undef pid_t
56 #undef rlim_t
57 #undef ssize_t
58 #undef vfork
59 #include "tconfig.h"
60 #include "tsystem.h"
61 #include "coretypes.h"
62 #include "tm.h"
63 #include "libgcc_tm.h"
64 #include "unwind-dw2-fde.h"
66 #ifndef FORCE_CODE_SECTION_ALIGN
67 # define FORCE_CODE_SECTION_ALIGN
68 #endif
70 #ifndef CRT_CALL_STATIC_FUNCTION
71 # define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
72 static void __attribute__((__used__)) \
73 call_ ## FUNC (void) \
74 { \
75 asm (SECTION_OP); \
76 FUNC (); \
77 FORCE_CODE_SECTION_ALIGN \
78 asm (TEXT_SECTION_ASM_OP); \
80 #endif
82 #if defined(OBJECT_FORMAT_ELF) \
83 && !defined(OBJECT_FORMAT_FLAT) \
84 && defined(HAVE_LD_EH_FRAME_HDR) \
85 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
86 && defined(__FreeBSD__) && __FreeBSD__ >= 7
87 #include <link.h>
88 # define USE_PT_GNU_EH_FRAME
89 #endif
91 #if defined(OBJECT_FORMAT_ELF) \
92 && !defined(OBJECT_FORMAT_FLAT) \
93 && defined(HAVE_LD_EH_FRAME_HDR) && defined(TARGET_DL_ITERATE_PHDR) \
94 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
95 && defined(__sun__) && defined(__svr4__)
96 #include <link.h>
97 # define USE_PT_GNU_EH_FRAME
98 #endif
100 #if defined(OBJECT_FORMAT_ELF) \
101 && !defined(OBJECT_FORMAT_FLAT) \
102 && defined(HAVE_LD_EH_FRAME_HDR) \
103 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
104 && defined(__GLIBC__) && __GLIBC__ >= 2
105 #include <link.h>
106 /* uClibc pretends to be glibc 2.2 and DT_CONFIG is defined in its link.h.
107 But it doesn't use PT_GNU_EH_FRAME ELF segment currently. */
108 # if !defined(__UCLIBC__) \
109 && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
110 || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
111 # define USE_PT_GNU_EH_FRAME
112 # endif
113 #endif
115 #if defined(OBJECT_FORMAT_ELF) \
116 && !defined(OBJECT_FORMAT_FLAT) \
117 && defined(HAVE_LD_EH_FRAME_HDR) \
118 && !defined(CRTSTUFFT_O) \
119 && defined(inhibit_libc) \
120 && (defined(__GLIBC__) || defined(__gnu_linux__) || defined(__GNU__))
121 /* On systems using glibc, an inhibit_libc build of libgcc is only
122 part of a bootstrap process. Build the same crt*.o as would be
123 built with headers present, so that it is not necessary to build
124 glibc more than once for the bootstrap to converge. */
125 # define USE_PT_GNU_EH_FRAME
126 #endif
128 #if defined(EH_FRAME_SECTION_NAME) && !defined(USE_PT_GNU_EH_FRAME)
129 # define USE_EH_FRAME_REGISTRY
130 #endif
131 #if defined(EH_FRAME_SECTION_NAME) && EH_TABLES_CAN_BE_READ_ONLY
132 # define EH_FRAME_SECTION_CONST const
133 #else
134 # define EH_FRAME_SECTION_CONST
135 #endif
137 #if !defined(DTOR_LIST_END) && defined(OBJECT_FORMAT_ELF) \
138 && defined(HAVE_GAS_HIDDEN) && !defined(FINI_ARRAY_SECTION_ASM_OP)
139 # define HIDDEN_DTOR_LIST_END
140 #endif
142 #if !defined(USE_TM_CLONE_REGISTRY) && defined(OBJECT_FORMAT_ELF)
143 # define USE_TM_CLONE_REGISTRY 1
144 #endif
146 /* We do not want to add the weak attribute to the declarations of these
147 routines in unwind-dw2-fde.h because that will cause the definition of
148 these symbols to be weak as well.
150 This exposes a core issue, how to handle creating weak references vs
151 how to create weak definitions. Either we have to have the definition
152 of TARGET_WEAK_ATTRIBUTE be conditional in the shared header files or
153 have a second declaration if we want a function's references to be weak,
154 but not its definition.
156 Making TARGET_WEAK_ATTRIBUTE conditional seems like a good solution until
157 one thinks about scaling to larger problems -- i.e., the condition under
158 which TARGET_WEAK_ATTRIBUTE is active will eventually get far too
159 complicated.
161 So, we take an approach similar to #pragma weak -- we have a second
162 declaration for functions that we want to have weak references.
164 Neither way is particularly good. */
166 /* References to __register_frame_info and __deregister_frame_info should
167 be weak in this file if at all possible. */
168 extern void __register_frame_info (const void *, struct object *)
169 TARGET_ATTRIBUTE_WEAK;
170 extern void __register_frame_info_bases (const void *, struct object *,
171 void *, void *)
172 TARGET_ATTRIBUTE_WEAK;
173 extern void *__deregister_frame_info (const void *)
174 TARGET_ATTRIBUTE_WEAK;
175 extern void *__deregister_frame_info_bases (const void *)
176 TARGET_ATTRIBUTE_WEAK;
177 extern void __do_global_ctors_1 (void);
179 /* Likewise for _Jv_RegisterClasses. */
180 extern void _Jv_RegisterClasses (void *) TARGET_ATTRIBUTE_WEAK;
182 /* Likewise for transactional memory clone tables. */
183 extern void _ITM_registerTMCloneTable (void *, size_t) TARGET_ATTRIBUTE_WEAK;
184 extern void _ITM_deregisterTMCloneTable (void *) TARGET_ATTRIBUTE_WEAK;
186 #ifdef OBJECT_FORMAT_ELF
188 /* Declare a pointer to void function type. */
189 typedef void (*func_ptr) (void);
190 #define STATIC static
192 #else /* OBJECT_FORMAT_ELF */
194 #include "gbl-ctors.h"
196 #define STATIC
198 #endif /* OBJECT_FORMAT_ELF */
200 #ifdef CRT_BEGIN
202 /* NOTE: In order to be able to support SVR4 shared libraries, we arrange
203 to have one set of symbols { __CTOR_LIST__, __DTOR_LIST__, __CTOR_END__,
204 __DTOR_END__ } per root executable and also one set of these symbols
205 per shared library. So in any given whole process image, we may have
206 multiple definitions of each of these symbols. In order to prevent
207 these definitions from conflicting with one another, and in order to
208 ensure that the proper lists are used for the initialization/finalization
209 of each individual shared library (respectively), we give these symbols
210 only internal (i.e. `static') linkage, and we also make it a point to
211 refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__
212 symbol in crtbegin.o, where they are defined. */
214 /* No need for .ctors/.dtors section if linker can place them in
215 .init_array/.fini_array section. */
216 #ifndef USE_INITFINI_ARRAY
217 /* The -1 is a flag to __do_global_[cd]tors indicating that this table
218 does not start with a count of elements. */
219 #ifdef CTOR_LIST_BEGIN
220 CTOR_LIST_BEGIN;
221 #elif defined(CTORS_SECTION_ASM_OP)
222 /* Hack: force cc1 to switch to .data section early, so that assembling
223 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
224 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
225 asm (CTORS_SECTION_ASM_OP);
226 STATIC func_ptr __CTOR_LIST__[1]
227 __attribute__ ((__used__, aligned(sizeof(func_ptr))))
228 = { (func_ptr) (-1) };
229 #else
230 STATIC func_ptr __CTOR_LIST__[1]
231 __attribute__ ((__used__, section(".ctors"), aligned(sizeof(func_ptr))))
232 = { (func_ptr) (-1) };
233 #endif /* __CTOR_LIST__ alternatives */
235 #ifdef DTOR_LIST_BEGIN
236 DTOR_LIST_BEGIN;
237 #elif defined(DTORS_SECTION_ASM_OP)
238 asm (DTORS_SECTION_ASM_OP);
239 STATIC func_ptr __DTOR_LIST__[1]
240 __attribute__ ((aligned(sizeof(func_ptr))))
241 = { (func_ptr) (-1) };
242 #else
243 STATIC func_ptr __DTOR_LIST__[1]
244 __attribute__((section(".dtors"), aligned(sizeof(func_ptr))))
245 = { (func_ptr) (-1) };
246 #endif /* __DTOR_LIST__ alternatives */
247 #endif /* USE_INITFINI_ARRAY */
249 #ifdef USE_EH_FRAME_REGISTRY
250 /* Stick a label at the beginning of the frame unwind info so we can register
251 and deregister it with the exception handling library code. */
252 STATIC EH_FRAME_SECTION_CONST char __EH_FRAME_BEGIN__[]
253 __attribute__((section(EH_FRAME_SECTION_NAME), aligned(4)))
254 = { };
255 #endif /* USE_EH_FRAME_REGISTRY */
257 #ifdef JCR_SECTION_NAME
258 /* Stick a label at the beginning of the java class registration info
259 so we can register them properly. */
260 STATIC void *__JCR_LIST__[]
261 __attribute__ ((used, section(JCR_SECTION_NAME), aligned(sizeof(void*))))
262 = { };
263 #endif /* JCR_SECTION_NAME */
265 #if USE_TM_CLONE_REGISTRY
266 STATIC func_ptr __TMC_LIST__[]
267 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void*))))
268 = { };
269 # ifdef HAVE_GAS_HIDDEN
270 extern func_ptr __TMC_END__[] __attribute__((__visibility__ ("hidden")));
271 # endif
273 static inline void
274 deregister_tm_clones (void)
276 void (*fn) (void *);
278 #ifdef HAVE_GAS_HIDDEN
279 if (__TMC_END__ - __TMC_LIST__ == 0)
280 return;
281 #else
282 if (__TMC_LIST__[0] == NULL)
283 return;
284 #endif
286 fn = _ITM_deregisterTMCloneTable;
287 __asm ("" : "+r" (fn));
288 if (fn)
289 fn (__TMC_LIST__);
292 static inline void
293 register_tm_clones (void)
295 void (*fn) (void *, size_t);
296 size_t size;
298 #ifdef HAVE_GAS_HIDDEN
299 size = (__TMC_END__ - __TMC_LIST__) / 2;
300 #else
301 for (size = 0; __TMC_LIST__[size * 2] != NULL; size++)
302 continue;
303 #endif
304 if (size == 0)
305 return;
307 fn = _ITM_registerTMCloneTable;
308 __asm ("" : "+r" (fn));
309 if (fn)
310 fn (__TMC_LIST__, size);
312 #endif /* USE_TM_CLONE_REGISTRY */
314 #if defined(INIT_SECTION_ASM_OP) || defined(INIT_ARRAY_SECTION_ASM_OP)
316 #ifdef OBJECT_FORMAT_ELF
318 /* Declare the __dso_handle variable. It should have a unique value
319 in every shared-object; in a main program its value is zero. The
320 object should in any case be protected. This means the instance
321 in one DSO or the main program is not used in another object. The
322 dynamic linker takes care of this. */
324 #ifdef TARGET_LIBGCC_SDATA_SECTION
325 extern void *__dso_handle __attribute__ ((__section__ (TARGET_LIBGCC_SDATA_SECTION)));
326 #endif
327 #ifdef HAVE_GAS_HIDDEN
328 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
329 #endif
330 #ifdef CRTSTUFFS_O
331 void *__dso_handle = &__dso_handle;
332 #else
333 void *__dso_handle = 0;
334 #endif
336 /* The __cxa_finalize function may not be available so we use only a
337 weak declaration. */
338 extern void __cxa_finalize (void *) TARGET_ATTRIBUTE_WEAK;
340 /* Run all the global destructors on exit from the program. */
342 /* Some systems place the number of pointers in the first word of the
343 table. On SVR4 however, that word is -1. In all cases, the table is
344 null-terminated. On SVR4, we start from the beginning of the list and
345 invoke each per-compilation-unit destructor routine in order
346 until we find that null.
348 Note that this function MUST be static. There will be one of these
349 functions in each root executable and one in each shared library, but
350 although they all have the same code, each one is unique in that it
351 refers to one particular associated `__DTOR_LIST__' which belongs to the
352 same particular root executable or shared library file.
354 On some systems, this routine is run more than once from the .fini,
355 when exit is called recursively, so we arrange to remember where in
356 the list we left off processing, and we resume at that point,
357 should we be re-invoked. */
359 static void __attribute__((used))
360 __do_global_dtors_aux (void)
362 static _Bool completed;
364 if (__builtin_expect (completed, 0))
365 return;
367 #ifdef CRTSTUFFS_O
368 if (__cxa_finalize)
369 __cxa_finalize (__dso_handle);
370 #endif
372 #ifdef FINI_ARRAY_SECTION_ASM_OP
373 /* If we are using .fini_array then destructors will be run via that
374 mechanism. */
375 #elif defined(HIDDEN_DTOR_LIST_END)
377 /* Safer version that makes sure only .dtors function pointers are
378 called even if the static variable is maliciously changed. */
379 extern func_ptr __DTOR_END__[] __attribute__((visibility ("hidden")));
380 static size_t dtor_idx;
381 const size_t max_idx = __DTOR_END__ - __DTOR_LIST__ - 1;
382 func_ptr f;
384 while (dtor_idx < max_idx)
386 f = __DTOR_LIST__[++dtor_idx];
387 f ();
390 #else /* !defined (FINI_ARRAY_SECTION_ASM_OP) */
392 static func_ptr *p = __DTOR_LIST__ + 1;
393 func_ptr f;
395 while ((f = *p))
397 p++;
398 f ();
401 #endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
403 #if USE_TM_CLONE_REGISTRY
404 deregister_tm_clones ();
405 #endif /* USE_TM_CLONE_REGISTRY */
407 #ifdef USE_EH_FRAME_REGISTRY
408 #ifdef CRT_GET_RFIB_DATA
409 /* If we used the new __register_frame_info_bases interface,
410 make sure that we deregister from the same place. */
411 if (__deregister_frame_info_bases)
412 __deregister_frame_info_bases (__EH_FRAME_BEGIN__);
413 #else
414 if (__deregister_frame_info)
415 __deregister_frame_info (__EH_FRAME_BEGIN__);
416 #endif
417 #endif
419 completed = 1;
422 /* Stick a call to __do_global_dtors_aux into the .fini section. */
423 #ifdef FINI_SECTION_ASM_OP
424 CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux)
425 #elif defined (FINI_ARRAY_SECTION_ASM_OP)
426 static func_ptr __do_global_dtors_aux_fini_array_entry[]
427 __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr))))
428 = { __do_global_dtors_aux };
429 #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */
430 static void __attribute__((used))
431 __do_global_dtors_aux_1 (void)
433 atexit (__do_global_dtors_aux);
435 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_dtors_aux_1)
436 #endif
438 #if defined(USE_EH_FRAME_REGISTRY) \
439 || defined(JCR_SECTION_NAME) \
440 || defined(USE_TM_CLONE_REGISTRY)
441 /* Stick a call to __register_frame_info into the .init section. For some
442 reason calls with no arguments work more reliably in .init, so stick the
443 call in another function. */
445 static void __attribute__((used))
446 frame_dummy (void)
448 #ifdef USE_EH_FRAME_REGISTRY
449 static struct object object;
450 #ifdef CRT_GET_RFIB_DATA
451 void *tbase, *dbase;
452 tbase = 0;
453 CRT_GET_RFIB_DATA (dbase);
454 if (__register_frame_info_bases)
455 __register_frame_info_bases (__EH_FRAME_BEGIN__, &object, tbase, dbase);
456 #else
457 if (__register_frame_info)
458 __register_frame_info (__EH_FRAME_BEGIN__, &object);
459 #endif /* CRT_GET_RFIB_DATA */
460 #endif /* USE_EH_FRAME_REGISTRY */
462 #ifdef JCR_SECTION_NAME
463 if (__JCR_LIST__[0])
465 void (*register_classes) (void *) = _Jv_RegisterClasses;
466 __asm ("" : "+r" (register_classes));
467 if (register_classes)
468 register_classes (__JCR_LIST__);
470 #endif /* JCR_SECTION_NAME */
472 #if USE_TM_CLONE_REGISTRY
473 register_tm_clones ();
474 #endif /* USE_TM_CLONE_REGISTRY */
477 #ifdef INIT_SECTION_ASM_OP
478 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, frame_dummy)
479 #else /* defined(INIT_SECTION_ASM_OP) */
480 static func_ptr __frame_dummy_init_array_entry[]
481 __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr))))
482 = { frame_dummy };
483 #endif /* !defined(INIT_SECTION_ASM_OP) */
484 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
486 #else /* OBJECT_FORMAT_ELF */
488 /* The function __do_global_ctors_aux is compiled twice (once in crtbegin.o
489 and once in crtend.o). It must be declared static to avoid a link
490 error. Here, we define __do_global_ctors as an externally callable
491 function. It is externally callable so that __main can invoke it when
492 INVOKE__main is defined. This has the additional effect of forcing cc1
493 to switch to the .text section. */
495 static void __do_global_ctors_aux (void);
496 void
497 __do_global_ctors (void)
499 #ifdef INVOKE__main
500 /* If __main won't actually call __do_global_ctors then it doesn't matter
501 what's inside the function. The inside of __do_global_ctors_aux is
502 called automatically in that case. And the Alliant fx2800 linker
503 crashes on this reference. So prevent the crash. */
504 __do_global_ctors_aux ();
505 #endif
508 asm (INIT_SECTION_ASM_OP); /* cc1 doesn't know that we are switching! */
510 /* A routine to invoke all of the global constructors upon entry to the
511 program. We put this into the .init section (for systems that have
512 such a thing) so that we can properly perform the construction of
513 file-scope static-storage C++ objects within shared libraries. */
515 static void __attribute__((used))
516 __do_global_ctors_aux (void) /* prologue goes in .init section */
518 FORCE_CODE_SECTION_ALIGN /* explicit align before switch to .text */
519 asm (TEXT_SECTION_ASM_OP); /* don't put epilogue and body in .init */
520 DO_GLOBAL_CTORS_BODY;
521 atexit (__do_global_dtors);
524 #endif /* OBJECT_FORMAT_ELF */
526 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
528 extern void __do_global_dtors (void);
530 /* This case is used by the Irix 6 port, which supports named sections but
531 not an SVR4-style .fini section. __do_global_dtors can be non-static
532 in this case because we protect it with -hidden_symbol. */
534 void
535 __do_global_dtors (void)
537 func_ptr *p, f;
538 for (p = __DTOR_LIST__ + 1; (f = *p); p++)
539 f ();
541 #if USE_TM_CLONE_REGISTRY
542 deregister_tm_clones ();
543 #endif /* USE_TM_CLONE_REGISTRY */
545 #ifdef USE_EH_FRAME_REGISTRY
546 if (__deregister_frame_info)
547 __deregister_frame_info (__EH_FRAME_BEGIN__);
548 #endif
551 #if defined(USE_EH_FRAME_REGISTRY) \
552 || defined(JCR_SECTION_NAME) \
553 || defined(USE_TM_CLONE_REGISTRY)
554 /* A helper function for __do_global_ctors, which is in crtend.o. Here
555 in crtbegin.o, we can reference a couple of symbols not visible there.
556 Plus, since we're before libgcc.a, we have no problems referencing
557 functions from there. */
558 void
559 __do_global_ctors_1(void)
561 #ifdef USE_EH_FRAME_REGISTRY
562 static struct object object;
563 if (__register_frame_info)
564 __register_frame_info (__EH_FRAME_BEGIN__, &object);
565 #endif
567 #ifdef JCR_SECTION_NAME
568 if (__JCR_LIST__[0])
570 void (*register_classes) (void *) = _Jv_RegisterClasses;
571 __asm ("" : "+r" (register_classes));
572 if (register_classes)
573 register_classes (__JCR_LIST__);
575 #endif
577 #if USE_TM_CLONE_REGISTRY
578 register_tm_clones ();
579 #endif /* USE_TM_CLONE_REGISTRY */
581 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
583 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
584 #error "What are you doing with crtstuff.c, then?"
585 #endif
587 #elif defined(CRT_END) /* ! CRT_BEGIN */
589 /* No need for .ctors/.dtors section if linker can place them in
590 .init_array/.fini_array section. */
591 #ifndef USE_INITFINI_ARRAY
592 /* Put a word containing zero at the end of each of our two lists of function
593 addresses. Note that the words defined here go into the .ctors and .dtors
594 sections of the crtend.o file, and since that file is always linked in
595 last, these words naturally end up at the very ends of the two lists
596 contained in these two sections. */
598 #ifdef CTOR_LIST_END
599 CTOR_LIST_END;
600 #elif defined(CTORS_SECTION_ASM_OP)
601 /* Hack: force cc1 to switch to .data section early, so that assembling
602 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
603 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
604 asm (CTORS_SECTION_ASM_OP);
605 STATIC func_ptr __CTOR_END__[1]
606 __attribute__((aligned(sizeof(func_ptr))))
607 = { (func_ptr) 0 };
608 #else
609 STATIC func_ptr __CTOR_END__[1]
610 __attribute__((section(".ctors"), aligned(sizeof(func_ptr))))
611 = { (func_ptr) 0 };
612 #endif
614 #ifdef DTOR_LIST_END
615 DTOR_LIST_END;
616 #elif defined(HIDDEN_DTOR_LIST_END)
617 #ifdef DTORS_SECTION_ASM_OP
618 asm (DTORS_SECTION_ASM_OP);
619 #endif
620 func_ptr __DTOR_END__[1]
621 __attribute__ ((used,
622 #ifndef DTORS_SECTION_ASM_OP
623 section(".dtors"),
624 #endif
625 aligned(sizeof(func_ptr)), visibility ("hidden")))
626 = { (func_ptr) 0 };
627 #elif defined(DTORS_SECTION_ASM_OP)
628 asm (DTORS_SECTION_ASM_OP);
629 STATIC func_ptr __DTOR_END__[1]
630 __attribute__ ((used, aligned(sizeof(func_ptr))))
631 = { (func_ptr) 0 };
632 #else
633 STATIC func_ptr __DTOR_END__[1]
634 __attribute__((used, section(".dtors"), aligned(sizeof(func_ptr))))
635 = { (func_ptr) 0 };
636 #endif
637 #endif /* USE_INITFINI_ARRAY */
639 #ifdef EH_FRAME_SECTION_NAME
640 /* Terminate the frame unwind info section with a 4byte 0 as a sentinel;
641 this would be the 'length' field in a real FDE. */
642 # if __INT_MAX__ == 2147483647
643 typedef int int32;
644 # elif __LONG_MAX__ == 2147483647
645 typedef long int32;
646 # elif __SHRT_MAX__ == 2147483647
647 typedef short int32;
648 # else
649 # error "Missing a 4 byte integer"
650 # endif
651 STATIC EH_FRAME_SECTION_CONST int32 __FRAME_END__[]
652 __attribute__ ((used, section(EH_FRAME_SECTION_NAME),
653 aligned(sizeof(int32))))
654 = { 0 };
655 #endif /* EH_FRAME_SECTION_NAME */
657 #ifdef JCR_SECTION_NAME
658 /* Null terminate the .jcr section array. */
659 STATIC void *__JCR_END__[1]
660 __attribute__ ((used, section(JCR_SECTION_NAME),
661 aligned(sizeof(void *))))
662 = { 0 };
663 #endif /* JCR_SECTION_NAME */
665 #if USE_TM_CLONE_REGISTRY
666 # ifndef HAVE_GAS_HIDDEN
667 static
668 # endif
669 func_ptr __TMC_END__[]
670 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void *))))
671 # ifdef HAVE_GAS_HIDDEN
672 __attribute__((__visibility__ ("hidden"))) = { };
673 # else
674 = { 0, 0 };
675 # endif
676 #endif /* USE_TM_CLONE_REGISTRY */
678 #ifdef INIT_ARRAY_SECTION_ASM_OP
680 /* If we are using .init_array, there is nothing to do. */
682 #elif defined(INIT_SECTION_ASM_OP)
684 #ifdef OBJECT_FORMAT_ELF
685 static void __attribute__((used))
686 __do_global_ctors_aux (void)
688 func_ptr *p;
689 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
690 (*p) ();
693 /* Stick a call to __do_global_ctors_aux into the .init section. */
694 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_ctors_aux)
695 #else /* OBJECT_FORMAT_ELF */
697 /* Stick the real initialization code, followed by a normal sort of
698 function epilogue at the very end of the .init section for this
699 entire root executable file or for this entire shared library file.
701 Note that we use some tricks here to get *just* the body and just
702 a function epilogue (but no function prologue) into the .init
703 section of the crtend.o file. Specifically, we switch to the .text
704 section, start to define a function, and then we switch to the .init
705 section just before the body code.
707 Earlier on, we put the corresponding function prologue into the .init
708 section of the crtbegin.o file (which will be linked in first).
710 Note that we want to invoke all constructors for C++ file-scope static-
711 storage objects AFTER any other possible initialization actions which
712 may be performed by the code in the .init section contributions made by
713 other libraries, etc. That's because those other initializations may
714 include setup operations for very primitive things (e.g. initializing
715 the state of the floating-point coprocessor, etc.) which should be done
716 before we start to execute any of the user's code. */
718 static void
719 __do_global_ctors_aux (void) /* prologue goes in .text section */
721 asm (INIT_SECTION_ASM_OP);
722 DO_GLOBAL_CTORS_BODY;
723 atexit (__do_global_dtors);
724 } /* epilogue and body go in .init section */
726 FORCE_CODE_SECTION_ALIGN
727 asm (TEXT_SECTION_ASM_OP);
729 #endif /* OBJECT_FORMAT_ELF */
731 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
733 extern void __do_global_ctors (void);
735 /* This case is used by the Irix 6 port, which supports named sections but
736 not an SVR4-style .init section. __do_global_ctors can be non-static
737 in this case because we protect it with -hidden_symbol. */
738 void
739 __do_global_ctors (void)
741 func_ptr *p;
742 #if defined(USE_EH_FRAME_REGISTRY) \
743 || defined(JCR_SECTION_NAME) \
744 || defined(USE_TM_CLONE_REGISTRY)
745 __do_global_ctors_1();
746 #endif
747 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
748 (*p) ();
751 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
752 #error "What are you doing with crtstuff.c, then?"
753 #endif
755 #else /* ! CRT_BEGIN && ! CRT_END */
756 #error "One of CRT_BEGIN or CRT_END must be defined."
757 #endif