1 /* Specialized bits of code needed to support construction and
2 destruction of file-scope objects in C++ code.
3 Copyright (C) 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001
4 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011
5 Free Software Foundation, Inc.
6 Contributed by Ron Guilmette (rfg@monkeys.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free
12 Software Foundation; either version 3, or (at your option) any later
15 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16 WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 Under Section 7 of GPL version 3, you are granted additional
21 permissions described in the GCC Runtime Library Exception, version
22 3.1, as published by the Free Software Foundation.
24 You should have received a copy of the GNU General Public License and
25 a copy of the GCC Runtime Library Exception along with this program;
26 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
27 <http://www.gnu.org/licenses/>. */
29 /* This file is a bit like libgcc2.c in that it is compiled
30 multiple times and yields multiple .o files.
32 This file is useful on target machines where the object file format
33 supports multiple "user-defined" sections (e.g. COFF, ELF, ROSE). On
34 such systems, this file allows us to avoid running collect (or any
35 other such slow and painful kludge). Additionally, if the target
36 system supports a .init section, this file allows us to support the
37 linking of C++ code with a non-C++ main program.
39 Note that if INIT_SECTION_ASM_OP is defined in the tm.h file, then
40 this file *will* make use of the .init section. If that symbol is
41 not defined however, then the .init section will not be used.
43 Currently, only ELF and COFF are supported. It is likely however that
44 ROSE could also be supported, if someone was willing to do the work to
45 make whatever (small?) adaptations are needed. (Some work may be
46 needed on the ROSE assembler and linker also.)
48 This file must be compiled with gcc. */
50 /* Target machine header files require this define. */
53 /* FIXME: Including auto-host is incorrect, but until we have
54 identified the set of defines that need to go into auto-target.h,
55 this will have to do. */
56 #include "auto-host.h"
63 #include "coretypes.h"
65 #include "libgcc_tm.h"
66 #include "unwind-dw2-fde.h"
68 #ifndef FORCE_CODE_SECTION_ALIGN
69 # define FORCE_CODE_SECTION_ALIGN
72 #ifndef CRT_CALL_STATIC_FUNCTION
73 # define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
74 static void __attribute__((__used__)) \
75 call_ ## FUNC (void) \
79 FORCE_CODE_SECTION_ALIGN \
80 asm (TEXT_SECTION_ASM_OP); \
84 #if defined(TARGET_DL_ITERATE_PHDR) && \
85 ( defined(__FreeBSD__) \
86 || defined(__OpenBSD__) \
87 || defined(__NetBSD__) \
88 || defined(__DragonFly__))
89 #define BSD_DL_ITERATE_PHDR_AVAILABLE
92 #if defined(OBJECT_FORMAT_ELF) \
93 && !defined(OBJECT_FORMAT_FLAT) \
94 && defined(HAVE_LD_EH_FRAME_HDR) \
95 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
96 && defined(BSD_DL_ITERATE_PHDR_AVAILABLE)
98 # define USE_PT_GNU_EH_FRAME
101 #if defined(OBJECT_FORMAT_ELF) \
102 && !defined(OBJECT_FORMAT_FLAT) \
103 && defined(HAVE_LD_EH_FRAME_HDR) && defined(TARGET_DL_ITERATE_PHDR) \
104 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
105 && defined(__sun__) && defined(__svr4__)
107 # define USE_PT_GNU_EH_FRAME
110 #if defined(OBJECT_FORMAT_ELF) \
111 && !defined(OBJECT_FORMAT_FLAT) \
112 && defined(HAVE_LD_EH_FRAME_HDR) \
113 && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
114 && defined(__GLIBC__) && __GLIBC__ >= 2
116 /* uClibc pretends to be glibc 2.2 and DT_CONFIG is defined in its link.h.
117 But it doesn't use PT_GNU_EH_FRAME ELF segment currently. */
118 # if !defined(__UCLIBC__) \
119 && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
120 || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
121 # define USE_PT_GNU_EH_FRAME
124 #if defined(EH_FRAME_SECTION_NAME) && !defined(USE_PT_GNU_EH_FRAME)
125 # define USE_EH_FRAME_REGISTRY
127 #if defined(EH_FRAME_SECTION_NAME) && EH_TABLES_CAN_BE_READ_ONLY
128 # define EH_FRAME_SECTION_CONST const
130 # define EH_FRAME_SECTION_CONST
133 #if !defined(DTOR_LIST_END) && defined(OBJECT_FORMAT_ELF) \
134 && defined(HAVE_GAS_HIDDEN) && !defined(FINI_ARRAY_SECTION_ASM_OP)
135 # define HIDDEN_DTOR_LIST_END
138 #if !defined(USE_TM_CLONE_REGISTRY) && defined(OBJECT_FORMAT_ELF)
139 # define USE_TM_CLONE_REGISTRY 1
142 /* We do not want to add the weak attribute to the declarations of these
143 routines in unwind-dw2-fde.h because that will cause the definition of
144 these symbols to be weak as well.
146 This exposes a core issue, how to handle creating weak references vs
147 how to create weak definitions. Either we have to have the definition
148 of TARGET_WEAK_ATTRIBUTE be conditional in the shared header files or
149 have a second declaration if we want a function's references to be weak,
150 but not its definition.
152 Making TARGET_WEAK_ATTRIBUTE conditional seems like a good solution until
153 one thinks about scaling to larger problems -- i.e., the condition under
154 which TARGET_WEAK_ATTRIBUTE is active will eventually get far too
157 So, we take an approach similar to #pragma weak -- we have a second
158 declaration for functions that we want to have weak references.
160 Neither way is particularly good. */
162 /* References to __register_frame_info and __deregister_frame_info should
163 be weak in this file if at all possible. */
164 extern void __register_frame_info (const void *, struct object *)
165 TARGET_ATTRIBUTE_WEAK;
166 extern void __register_frame_info_bases (const void *, struct object *,
168 TARGET_ATTRIBUTE_WEAK;
169 extern void *__deregister_frame_info (const void *)
170 TARGET_ATTRIBUTE_WEAK;
171 extern void *__deregister_frame_info_bases (const void *)
172 TARGET_ATTRIBUTE_WEAK;
173 extern void __do_global_ctors_1 (void);
175 /* Likewise for _Jv_RegisterClasses. */
176 extern void _Jv_RegisterClasses (void *) TARGET_ATTRIBUTE_WEAK;
178 /* Likewise for transactional memory clone tables. */
179 extern void _ITM_registerTMCloneTable (void *, size_t) TARGET_ATTRIBUTE_WEAK;
180 extern void _ITM_deregisterTMCloneTable (void *) TARGET_ATTRIBUTE_WEAK;
182 #ifdef OBJECT_FORMAT_ELF
184 /* Declare a pointer to void function type. */
185 typedef void (*func_ptr) (void);
186 #define STATIC static
188 #else /* OBJECT_FORMAT_ELF */
190 #include "gbl-ctors.h"
194 #endif /* OBJECT_FORMAT_ELF */
198 /* NOTE: In order to be able to support SVR4 shared libraries, we arrange
199 to have one set of symbols { __CTOR_LIST__, __DTOR_LIST__, __CTOR_END__,
200 __DTOR_END__ } per root executable and also one set of these symbols
201 per shared library. So in any given whole process image, we may have
202 multiple definitions of each of these symbols. In order to prevent
203 these definitions from conflicting with one another, and in order to
204 ensure that the proper lists are used for the initialization/finalization
205 of each individual shared library (respectively), we give these symbols
206 only internal (i.e. `static') linkage, and we also make it a point to
207 refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__
208 symbol in crtbegin.o, where they are defined. */
210 /* No need for .ctors/.dtors section if linker can place them in
211 .init_array/.fini_array section. */
212 #ifndef USE_INITFINI_ARRAY
213 /* The -1 is a flag to __do_global_[cd]tors indicating that this table
214 does not start with a count of elements. */
215 #ifdef CTOR_LIST_BEGIN
217 #elif defined(CTORS_SECTION_ASM_OP)
218 /* Hack: force cc1 to switch to .data section early, so that assembling
219 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
220 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
221 asm (CTORS_SECTION_ASM_OP);
222 STATIC func_ptr __CTOR_LIST__[1]
223 __attribute__ ((__used__, aligned(sizeof(func_ptr))))
224 = { (func_ptr) (-1) };
226 STATIC func_ptr __CTOR_LIST__[1]
227 __attribute__ ((__used__, section(".ctors"), aligned(sizeof(func_ptr))))
228 = { (func_ptr) (-1) };
229 #endif /* __CTOR_LIST__ alternatives */
231 #ifdef DTOR_LIST_BEGIN
233 #elif defined(DTORS_SECTION_ASM_OP)
234 asm (DTORS_SECTION_ASM_OP);
235 STATIC func_ptr __DTOR_LIST__[1]
236 __attribute__ ((aligned(sizeof(func_ptr))))
237 = { (func_ptr) (-1) };
239 STATIC func_ptr __DTOR_LIST__[1]
240 __attribute__((section(".dtors"), aligned(sizeof(func_ptr))))
241 = { (func_ptr) (-1) };
242 #endif /* __DTOR_LIST__ alternatives */
243 #endif /* USE_INITFINI_ARRAY */
245 #ifdef USE_EH_FRAME_REGISTRY
246 /* Stick a label at the beginning of the frame unwind info so we can register
247 and deregister it with the exception handling library code. */
248 STATIC EH_FRAME_SECTION_CONST char __EH_FRAME_BEGIN__[]
249 __attribute__((section(EH_FRAME_SECTION_NAME), aligned(4)))
251 #endif /* USE_EH_FRAME_REGISTRY */
253 #ifdef JCR_SECTION_NAME
254 /* Stick a label at the beginning of the java class registration info
255 so we can register them properly. */
256 STATIC void *__JCR_LIST__[]
257 __attribute__ ((used, section(JCR_SECTION_NAME), aligned(sizeof(void*))))
259 #endif /* JCR_SECTION_NAME */
261 #if USE_TM_CLONE_REGISTRY
262 STATIC func_ptr __TMC_LIST__[]
263 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void*))))
265 # ifdef HAVE_GAS_HIDDEN
266 extern func_ptr __TMC_END__[] __attribute__((__visibility__ ("hidden")));
270 deregister_tm_clones (void)
274 #ifdef HAVE_GAS_HIDDEN
275 if (__TMC_END__ - __TMC_LIST__ == 0)
278 if (__TMC_LIST__[0] == NULL)
282 fn = _ITM_deregisterTMCloneTable;
283 __asm ("" : "+r" (fn));
289 register_tm_clones (void)
291 void (*fn) (void *, size_t);
294 #ifdef HAVE_GAS_HIDDEN
295 size = (__TMC_END__ - __TMC_LIST__) / 2;
297 for (size = 0; __TMC_LIST__[size * 2] != NULL; size++)
303 fn = _ITM_registerTMCloneTable;
304 __asm ("" : "+r" (fn));
306 fn (__TMC_LIST__, size);
308 #endif /* USE_TM_CLONE_REGISTRY */
310 #if defined(INIT_SECTION_ASM_OP) || defined(INIT_ARRAY_SECTION_ASM_OP)
312 #ifdef OBJECT_FORMAT_ELF
314 /* Declare the __dso_handle variable. It should have a unique value
315 in every shared-object; in a main program its value is zero. The
316 object should in any case be protected. This means the instance
317 in one DSO or the main program is not used in another object. The
318 dynamic linker takes care of this. */
320 #ifdef TARGET_LIBGCC_SDATA_SECTION
321 extern void *__dso_handle __attribute__ ((__section__ (TARGET_LIBGCC_SDATA_SECTION)));
323 #ifdef HAVE_GAS_HIDDEN
324 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
327 void *__dso_handle = &__dso_handle;
329 void *__dso_handle = 0;
332 /* The __cxa_finalize function may not be available so we use only a
334 extern void __cxa_finalize (void *) TARGET_ATTRIBUTE_WEAK;
336 /* Run all the global destructors on exit from the program. */
338 /* Some systems place the number of pointers in the first word of the
339 table. On SVR4 however, that word is -1. In all cases, the table is
340 null-terminated. On SVR4, we start from the beginning of the list and
341 invoke each per-compilation-unit destructor routine in order
342 until we find that null.
344 Note that this function MUST be static. There will be one of these
345 functions in each root executable and one in each shared library, but
346 although they all have the same code, each one is unique in that it
347 refers to one particular associated `__DTOR_LIST__' which belongs to the
348 same particular root executable or shared library file.
350 On some systems, this routine is run more than once from the .fini,
351 when exit is called recursively, so we arrange to remember where in
352 the list we left off processing, and we resume at that point,
353 should we be re-invoked. */
355 static void __attribute__((used))
356 __do_global_dtors_aux (void)
358 static _Bool completed;
360 if (__builtin_expect (completed, 0))
365 __cxa_finalize (__dso_handle);
368 #ifdef FINI_ARRAY_SECTION_ASM_OP
369 /* If we are using .fini_array then destructors will be run via that
371 #elif defined(HIDDEN_DTOR_LIST_END)
373 /* Safer version that makes sure only .dtors function pointers are
374 called even if the static variable is maliciously changed. */
375 extern func_ptr __DTOR_END__[] __attribute__((visibility ("hidden")));
376 static size_t dtor_idx;
377 const size_t max_idx = __DTOR_END__ - __DTOR_LIST__ - 1;
380 while (dtor_idx < max_idx)
382 f = __DTOR_LIST__[++dtor_idx];
386 #else /* !defined (FINI_ARRAY_SECTION_ASM_OP) */
388 static func_ptr *p = __DTOR_LIST__ + 1;
397 #endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
399 #if USE_TM_CLONE_REGISTRY
400 deregister_tm_clones ();
401 #endif /* USE_TM_CLONE_REGISTRY */
403 #ifdef USE_EH_FRAME_REGISTRY
404 #ifdef CRT_GET_RFIB_DATA
405 /* If we used the new __register_frame_info_bases interface,
406 make sure that we deregister from the same place. */
407 if (__deregister_frame_info_bases)
408 __deregister_frame_info_bases (__EH_FRAME_BEGIN__);
410 if (__deregister_frame_info)
411 __deregister_frame_info (__EH_FRAME_BEGIN__);
418 /* Stick a call to __do_global_dtors_aux into the .fini section. */
419 #ifdef FINI_SECTION_ASM_OP
420 CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux)
421 #elif defined (FINI_ARRAY_SECTION_ASM_OP)
422 static func_ptr __do_global_dtors_aux_fini_array_entry[]
423 __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr))))
424 = { __do_global_dtors_aux };
425 #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */
426 static void __attribute__((used))
427 __do_global_dtors_aux_1 (void)
429 atexit (__do_global_dtors_aux);
431 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_dtors_aux_1)
434 #if defined(USE_EH_FRAME_REGISTRY) \
435 || defined(JCR_SECTION_NAME) \
436 || defined(USE_TM_CLONE_REGISTRY)
437 /* Stick a call to __register_frame_info into the .init section. For some
438 reason calls with no arguments work more reliably in .init, so stick the
439 call in another function. */
441 static void __attribute__((used))
444 #ifdef USE_EH_FRAME_REGISTRY
445 static struct object object;
446 #ifdef CRT_GET_RFIB_DATA
449 CRT_GET_RFIB_DATA (dbase);
450 if (__register_frame_info_bases)
451 __register_frame_info_bases (__EH_FRAME_BEGIN__, &object, tbase, dbase);
453 if (__register_frame_info)
454 __register_frame_info (__EH_FRAME_BEGIN__, &object);
455 #endif /* CRT_GET_RFIB_DATA */
456 #endif /* USE_EH_FRAME_REGISTRY */
458 #ifdef JCR_SECTION_NAME
461 void (*register_classes) (void *) = _Jv_RegisterClasses;
462 __asm ("" : "+r" (register_classes));
463 if (register_classes)
464 register_classes (__JCR_LIST__);
466 #endif /* JCR_SECTION_NAME */
468 #if USE_TM_CLONE_REGISTRY
469 register_tm_clones ();
470 #endif /* USE_TM_CLONE_REGISTRY */
473 #ifdef INIT_SECTION_ASM_OP
474 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, frame_dummy)
475 #else /* defined(INIT_SECTION_ASM_OP) */
476 static func_ptr __frame_dummy_init_array_entry[]
477 __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr))))
479 #endif /* !defined(INIT_SECTION_ASM_OP) */
480 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
482 #else /* OBJECT_FORMAT_ELF */
484 /* The function __do_global_ctors_aux is compiled twice (once in crtbegin.o
485 and once in crtend.o). It must be declared static to avoid a link
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. */
491 static void __do_global_ctors_aux (void);
493 __do_global_ctors (void)
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. */
500 __do_global_ctors_aux ();
504 asm (INIT_SECTION_ASM_OP); /* cc1 doesn't know that we are switching! */
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
509 file-scope static-storage C++ objects within shared libraries. */
511 static void __attribute__((used))
512 __do_global_ctors_aux (void) /* prologue goes in .init section */
514 FORCE_CODE_SECTION_ALIGN /* explicit align before switch to .text */
515 asm (TEXT_SECTION_ASM_OP); /* don't put epilogue and body in .init */
516 DO_GLOBAL_CTORS_BODY;
517 atexit (__do_global_dtors);
520 #endif /* OBJECT_FORMAT_ELF */
522 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
524 extern void __do_global_dtors (void);
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
528 in this case because we protect it with -hidden_symbol. */
531 __do_global_dtors (void)
534 for (p = __DTOR_LIST__ + 1; (f = *p); p++)
537 #if USE_TM_CLONE_REGISTRY
538 deregister_tm_clones ();
539 #endif /* USE_TM_CLONE_REGISTRY */
541 #ifdef USE_EH_FRAME_REGISTRY
542 if (__deregister_frame_info)
543 __deregister_frame_info (__EH_FRAME_BEGIN__);
547 #if defined(USE_EH_FRAME_REGISTRY) \
548 || defined(JCR_SECTION_NAME) \
549 || defined(USE_TM_CLONE_REGISTRY)
550 /* A helper function for __do_global_ctors, which is in crtend.o. Here
551 in crtbegin.o, we can reference a couple of symbols not visible there.
552 Plus, since we're before libgcc.a, we have no problems referencing
553 functions from there. */
555 __do_global_ctors_1(void)
557 #ifdef USE_EH_FRAME_REGISTRY
558 static struct object object;
559 if (__register_frame_info)
560 __register_frame_info (__EH_FRAME_BEGIN__, &object);
563 #ifdef JCR_SECTION_NAME
566 void (*register_classes) (void *) = _Jv_RegisterClasses;
567 __asm ("" : "+r" (register_classes));
568 if (register_classes)
569 register_classes (__JCR_LIST__);
573 #if USE_TM_CLONE_REGISTRY
574 register_tm_clones ();
575 #endif /* USE_TM_CLONE_REGISTRY */
577 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
579 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
580 #error "What are you doing with crtstuff.c, then?"
583 #elif defined(CRT_END) /* ! CRT_BEGIN */
585 /* No need for .ctors/.dtors section if linker can place them in
586 .init_array/.fini_array section. */
587 #ifndef USE_INITFINI_ARRAY
588 /* Put a word containing zero at the end of each of our two lists of function
589 addresses. Note that the words defined here go into the .ctors and .dtors
590 sections of the crtend.o file, and since that file is always linked in
591 last, these words naturally end up at the very ends of the two lists
592 contained in these two sections. */
596 #elif defined(CTORS_SECTION_ASM_OP)
597 /* Hack: force cc1 to switch to .data section early, so that assembling
598 __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */
599 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
600 asm (CTORS_SECTION_ASM_OP);
601 STATIC func_ptr __CTOR_END__[1]
602 __attribute__((aligned(sizeof(func_ptr))))
605 STATIC func_ptr __CTOR_END__[1]
606 __attribute__((section(".ctors"), aligned(sizeof(func_ptr))))
612 #elif defined(HIDDEN_DTOR_LIST_END)
613 #ifdef DTORS_SECTION_ASM_OP
614 asm (DTORS_SECTION_ASM_OP);
616 func_ptr __DTOR_END__[1]
617 __attribute__ ((used,
618 #ifndef DTORS_SECTION_ASM_OP
621 aligned(sizeof(func_ptr)), visibility ("hidden")))
623 #elif defined(DTORS_SECTION_ASM_OP)
624 asm (DTORS_SECTION_ASM_OP);
625 STATIC func_ptr __DTOR_END__[1]
626 __attribute__ ((used, aligned(sizeof(func_ptr))))
629 STATIC func_ptr __DTOR_END__[1]
630 __attribute__((used, section(".dtors"), aligned(sizeof(func_ptr))))
633 #endif /* USE_INITFINI_ARRAY */
635 #ifdef EH_FRAME_SECTION_NAME
636 /* Terminate the frame unwind info section with a 4byte 0 as a sentinel;
637 this would be the 'length' field in a real FDE. */
638 # if __INT_MAX__ == 2147483647
640 # elif __LONG_MAX__ == 2147483647
642 # elif __SHRT_MAX__ == 2147483647
645 # error "Missing a 4 byte integer"
647 STATIC EH_FRAME_SECTION_CONST int32 __FRAME_END__[]
648 __attribute__ ((used, section(EH_FRAME_SECTION_NAME),
649 aligned(sizeof(int32))))
651 #endif /* EH_FRAME_SECTION_NAME */
653 #ifdef JCR_SECTION_NAME
654 /* Null terminate the .jcr section array. */
655 STATIC void *__JCR_END__[1]
656 __attribute__ ((used, section(JCR_SECTION_NAME),
657 aligned(sizeof(void *))))
659 #endif /* JCR_SECTION_NAME */
661 #if USE_TM_CLONE_REGISTRY
662 # ifndef HAVE_GAS_HIDDEN
665 func_ptr __TMC_END__[]
666 __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void *))))
667 # ifdef HAVE_GAS_HIDDEN
668 __attribute__((__visibility__ ("hidden"))) = { };
672 #endif /* USE_TM_CLONE_REGISTRY */
674 #ifdef INIT_ARRAY_SECTION_ASM_OP
676 /* If we are using .init_array, there is nothing to do. */
678 #elif defined(INIT_SECTION_ASM_OP)
680 #ifdef OBJECT_FORMAT_ELF
681 static void __attribute__((used))
682 __do_global_ctors_aux (void)
685 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
689 /* Stick a call to __do_global_ctors_aux into the .init section. */
690 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_ctors_aux)
691 #else /* OBJECT_FORMAT_ELF */
693 /* Stick the real initialization code, followed by a normal sort of
694 function epilogue at the very end of the .init section for this
695 entire root executable file or for this entire shared library file.
697 Note that we use some tricks here to get *just* the body and just
698 a function epilogue (but no function prologue) into the .init
699 section of the crtend.o file. Specifically, we switch to the .text
700 section, start to define a function, and then we switch to the .init
701 section just before the body code.
703 Earlier on, we put the corresponding function prologue into the .init
704 section of the crtbegin.o file (which will be linked in first).
706 Note that we want to invoke all constructors for C++ file-scope static-
707 storage objects AFTER any other possible initialization actions which
708 may be performed by the code in the .init section contributions made by
709 other libraries, etc. That's because those other initializations may
710 include setup operations for very primitive things (e.g. initializing
711 the state of the floating-point coprocessor, etc.) which should be done
712 before we start to execute any of the user's code. */
715 __do_global_ctors_aux (void) /* prologue goes in .text section */
717 asm (INIT_SECTION_ASM_OP);
718 DO_GLOBAL_CTORS_BODY;
719 atexit (__do_global_dtors);
720 } /* epilogue and body go in .init section */
722 FORCE_CODE_SECTION_ALIGN
723 asm (TEXT_SECTION_ASM_OP);
725 #endif /* OBJECT_FORMAT_ELF */
727 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
729 extern void __do_global_ctors (void);
731 /* This case is used by the Irix 6 port, which supports named sections but
732 not an SVR4-style .init section. __do_global_ctors can be non-static
733 in this case because we protect it with -hidden_symbol. */
735 __do_global_ctors (void)
738 #if defined(USE_EH_FRAME_REGISTRY) \
739 || defined(JCR_SECTION_NAME) \
740 || defined(USE_TM_CLONE_REGISTRY)
741 __do_global_ctors_1();
743 for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
747 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
748 #error "What are you doing with crtstuff.c, then?"
751 #else /* ! CRT_BEGIN && ! CRT_END */
752 #error "One of CRT_BEGIN or CRT_END must be defined."