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9d13f5c4 | 1 | /* Specialized bits of code needed to support construction and |
2 | destruction of file-scope objects in C++ code. | |
00059bc7 | 3 | Copyright (C) 1991, 1994, 1995, 1996, 1997, 1998, |
ad565c04 | 4 | 1999, 2000, 2001 Free Software Foundation, Inc. |
31dcf09a | 5 | Contributed by Ron Guilmette (rfg@monkeys.com). |
9d13f5c4 | 6 | |
f12b58b3 | 7 | This file is part of GCC. |
9d13f5c4 | 8 | |
f12b58b3 | 9 | GCC is free software; you can redistribute it and/or modify it under |
10 | the terms of the GNU General Public License as published by the Free | |
11 | Software Foundation; either version 2, or (at your option) any later | |
12 | version. | |
9d13f5c4 | 13 | |
4c9b6e71 | 14 | In addition to the permissions in the GNU General Public License, the |
15 | Free Software Foundation gives you unlimited permission to link the | |
16 | compiled version of this file into combinations with other programs, | |
17 | and to distribute those combinations without any restriction coming | |
18 | from the use of this file. (The General Public License restrictions | |
19 | do apply in other respects; for example, they cover modification of | |
20 | the file, and distribution when not linked into a combine | |
21 | executable.) | |
22 | ||
f12b58b3 | 23 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
24 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
25 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
26 | for more details. | |
9d13f5c4 | 27 | |
28 | You should have received a copy of the GNU General Public License | |
f12b58b3 | 29 | along with GCC; see the file COPYING. If not, write to the Free |
30 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
31 | 02111-1307, USA. */ | |
9d13f5c4 | 32 | |
23573244 | 33 | /* This file is a bit like libgcc2.c in that it is compiled |
9d13f5c4 | 34 | multiple times and yields multiple .o files. |
35 | ||
36 | This file is useful on target machines where the object file format | |
37 | supports multiple "user-defined" sections (e.g. COFF, ELF, ROSE). On | |
38 | such systems, this file allows us to avoid running collect (or any | |
39 | other such slow and painful kludge). Additionally, if the target | |
40 | system supports a .init section, this file allows us to support the | |
41 | linking of C++ code with a non-C++ main program. | |
42 | ||
43 | Note that if INIT_SECTION_ASM_OP is defined in the tm.h file, then | |
44 | this file *will* make use of the .init section. If that symbol is | |
45 | not defined however, then the .init section will not be used. | |
46 | ||
5dd605c6 | 47 | Currently, only ELF and COFF are supported. It is likely however that |
48 | ROSE could also be supported, if someone was willing to do the work to | |
49 | make whatever (small?) adaptations are needed. (Some work may be | |
50 | needed on the ROSE assembler and linker also.) | |
9d13f5c4 | 51 | |
52 | This file must be compiled with gcc. */ | |
53 | ||
54 | /* It is incorrect to include config.h here, because this file is being | |
55 | compiled for the target, and hence definitions concerning only the host | |
56 | do not apply. */ | |
57 | ||
d07e08fa | 58 | /* We include auto-host.h here to get HAVE_GAS_HIDDEN. This is |
59 | supposedly valid even though this is a "target" file. */ | |
60 | #include "auto-host.h" | |
d826737c | 61 | #include "tconfig.h" |
069631e1 | 62 | #include "tsystem.h" |
df4b504c | 63 | #include "unwind-dw2-fde.h" |
9d13f5c4 | 64 | |
a815e00c | 65 | #ifndef CRT_CALL_STATIC_FUNCTION |
66 | # define CRT_CALL_STATIC_FUNCTION(func) func () | |
67 | #endif | |
68 | ||
ee055d40 | 69 | /* We do not want to add the weak attribute to the declarations of these |
df4b504c | 70 | routines in unwind-dw2-fde.h because that will cause the definition of |
71 | these symbols to be weak as well. | |
ee055d40 | 72 | |
73 | This exposes a core issue, how to handle creating weak references vs | |
74 | how to create weak definitions. Either we have to have the definition | |
75 | of TARGET_WEAK_ATTRIBUTE be conditional in the shared header files or | |
76 | have a second declaration if we want a function's references to be weak, | |
77 | but not its definition. | |
78 | ||
79 | Making TARGET_WEAK_ATTRIBUTE conditional seems like a good solution until | |
80 | one thinks about scaling to larger problems -- ie, the condition under | |
81 | which TARGET_WEAK_ATTRIBUTE is active will eventually get far too | |
82 | complicated. | |
83 | ||
84 | So, we take an approach similar to #pragma weak -- we have a second | |
85 | declaration for functions that we want to have weak references. | |
86 | ||
87 | Neither way is particularly good. */ | |
88 | ||
89 | /* References to __register_frame_info and __deregister_frame_info should | |
90 | be weak in this file if at all possible. */ | |
91 | extern void __register_frame_info (void *, struct object *) | |
92 | TARGET_ATTRIBUTE_WEAK; | |
f6338f42 | 93 | extern void __register_frame_info_bases (void *, struct object *, |
94 | void *, void *) | |
95 | TARGET_ATTRIBUTE_WEAK; | |
ee055d40 | 96 | extern void *__deregister_frame_info (void *) |
97 | TARGET_ATTRIBUTE_WEAK; | |
ce32d35f | 98 | extern void *__deregister_frame_info_bases (void *) |
99 | TARGET_ATTRIBUTE_WEAK; | |
ee055d40 | 100 | |
f313c0e1 | 101 | /* Likewise for _Jv_RegisterClasses. */ |
102 | extern void _Jv_RegisterClasses (void *) TARGET_ATTRIBUTE_WEAK; | |
103 | ||
5c61dffd | 104 | #ifndef OBJECT_FORMAT_MACHO |
105 | ||
b7c87ff2 | 106 | #ifdef OBJECT_FORMAT_ELF |
107 | ||
108 | /* Declare a pointer to void function type. */ | |
109 | typedef void (*func_ptr) (void); | |
110 | #define STATIC static | |
111 | ||
112 | #else /* OBJECT_FORMAT_ELF */ | |
113 | ||
9d13f5c4 | 114 | #include "gbl-ctors.h" |
115 | ||
b7c87ff2 | 116 | #define STATIC |
117 | ||
118 | #endif /* OBJECT_FORMAT_ELF */ | |
9d13f5c4 | 119 | |
120 | #ifdef CRT_BEGIN | |
121 | ||
f313c0e1 | 122 | /* NOTE: In order to be able to support SVR4 shared libraries, we arrange |
123 | to have one set of symbols { __CTOR_LIST__, __DTOR_LIST__, __CTOR_END__, | |
124 | __DTOR_END__ } per root executable and also one set of these symbols | |
125 | per shared library. So in any given whole process image, we may have | |
126 | multiple definitions of each of these symbols. In order to prevent | |
127 | these definitions from conflicting with one another, and in order to | |
128 | ensure that the proper lists are used for the initialization/finalization | |
129 | of each individual shared library (respectively), we give these symbols | |
130 | only internal (i.e. `static') linkage, and we also make it a point to | |
131 | refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__ | |
132 | symbol in crtbegin.o, where they are defined. */ | |
133 | ||
134 | /* The -1 is a flag to __do_global_[cd]tors indicating that this table | |
135 | does not start with a count of elements. */ | |
136 | #ifdef CTOR_LIST_BEGIN | |
137 | CTOR_LIST_BEGIN; | |
138 | #elif defined(CTORS_SECTION_ASM_OP) | |
139 | /* Hack: force cc1 to switch to .data section early, so that assembling | |
140 | __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */ | |
141 | static func_ptr force_to_data[1] __attribute__ ((__unused__)) = { }; | |
142 | asm (CTORS_SECTION_ASM_OP); | |
143 | STATIC func_ptr __CTOR_LIST__[1] | |
144 | __attribute__ ((__unused__, aligned(sizeof(func_ptr)))) | |
145 | = { (func_ptr) (-1) }; | |
146 | #else | |
147 | STATIC func_ptr __CTOR_LIST__[1] | |
148 | __attribute__ ((__unused__, section(".ctors"), aligned(sizeof(func_ptr)))) | |
149 | = { (func_ptr) (-1) }; | |
150 | #endif /* __CTOR_LIST__ alternatives */ | |
151 | ||
152 | #ifdef DTOR_LIST_BEGIN | |
153 | DTOR_LIST_BEGIN; | |
154 | #elif defined(DTORS_SECTION_ASM_OP) | |
155 | asm (DTORS_SECTION_ASM_OP); | |
156 | STATIC func_ptr __DTOR_LIST__[1] | |
157 | __attribute__ ((aligned(sizeof(func_ptr)))) | |
158 | = { (func_ptr) (-1) }; | |
159 | #else | |
160 | STATIC func_ptr __DTOR_LIST__[1] | |
161 | __attribute__((section(".dtors"), aligned(sizeof(func_ptr)))) | |
162 | = { (func_ptr) (-1) }; | |
163 | #endif /* __DTOR_LIST__ alternatives */ | |
164 | ||
165 | #ifdef EH_FRAME_SECTION_NAME | |
166 | /* Stick a label at the beginning of the frame unwind info so we can register | |
167 | and deregister it with the exception handling library code. */ | |
584907e7 | 168 | STATIC char __EH_FRAME_BEGIN__[] |
f313c0e1 | 169 | __attribute__((section(EH_FRAME_SECTION_NAME), aligned(4))) |
170 | = { }; | |
171 | #endif /* EH_FRAME_SECTION_NAME */ | |
172 | ||
173 | #ifdef JCR_SECTION_NAME | |
174 | /* Stick a label at the beginning of the java class registration info | |
175 | so we can register them properly. */ | |
f313c0e1 | 176 | STATIC void *__JCR_LIST__[] |
177 | __attribute__ ((unused, section(JCR_SECTION_NAME), aligned(sizeof(void*)))) | |
178 | = { }; | |
179 | #endif /* JCR_SECTION_NAME */ | |
180 | ||
584907e7 | 181 | #ifdef INIT_SECTION_ASM_OP |
182 | ||
b7c87ff2 | 183 | #ifdef OBJECT_FORMAT_ELF |
184 | ||
39b6af4b | 185 | /* Declare the __dso_handle variable. It should have a unique value |
5be729c9 | 186 | in every shared-object; in a main program its value is zero. The |
187 | object should in any case be protected. This means the instance | |
188 | in one DSO or the main program is not used in another object. The | |
189 | dynamic linker takes care of this. */ | |
190 | ||
191 | /* XXX Ideally the following should be implemented using | |
192 | __attribute__ ((__visibility__ ("hidden"))) | |
193 | but the __attribute__ support is not yet there. */ | |
194 | #ifdef HAVE_GAS_HIDDEN | |
195 | asm (".hidden\t__dso_handle"); | |
196 | #endif | |
39b6af4b | 197 | |
198 | #ifdef CRTSTUFFS_O | |
199 | void *__dso_handle = &__dso_handle; | |
200 | #else | |
201 | void *__dso_handle = 0; | |
202 | #endif | |
203 | ||
204 | /* The __cxa_finalize function may not be available so we use only a | |
205 | weak declaration. */ | |
206 | extern void __cxa_finalize (void *) TARGET_ATTRIBUTE_WEAK; | |
207 | ||
b7c87ff2 | 208 | /* Run all the global destructors on exit from the program. */ |
209 | ||
210 | /* Some systems place the number of pointers in the first word of the | |
211 | table. On SVR4 however, that word is -1. In all cases, the table is | |
212 | null-terminated. On SVR4, we start from the beginning of the list and | |
213 | invoke each per-compilation-unit destructor routine in order | |
214 | until we find that null. | |
215 | ||
216 | Note that this function MUST be static. There will be one of these | |
217 | functions in each root executable and one in each shared library, but | |
218 | although they all have the same code, each one is unique in that it | |
219 | refers to one particular associated `__DTOR_LIST__' which belongs to the | |
113f9ca7 | 220 | same particular root executable or shared library file. |
221 | ||
222 | On some systems, this routine is run more than once from the .fini, | |
223 | when exit is called recursively, so we arrange to remember where in | |
224 | the list we left off processing, and we resume at that point, | |
225 | should we be re-invoked. */ | |
b7c87ff2 | 226 | |
b7c87ff2 | 227 | static void |
aedb00bf | 228 | __do_global_dtors_aux (void) |
b7c87ff2 | 229 | { |
113f9ca7 | 230 | static func_ptr *p = __DTOR_LIST__ + 1; |
f6338f42 | 231 | static int completed; |
232 | func_ptr f; | |
dade0711 | 233 | |
f6338f42 | 234 | if (__builtin_expect (completed, 0)) |
dade0711 | 235 | return; |
236 | ||
f4513b3d | 237 | #ifdef CRTSTUFFS_O |
238 | if (__cxa_finalize) | |
39b6af4b | 239 | __cxa_finalize (__dso_handle); |
f4513b3d | 240 | #endif |
39b6af4b | 241 | |
f6338f42 | 242 | while ((f = *p)) |
113f9ca7 | 243 | { |
244 | p++; | |
f6338f42 | 245 | f (); |
113f9ca7 | 246 | } |
d757b8c9 | 247 | |
2cb4ac60 | 248 | #ifdef EH_FRAME_SECTION_NAME |
ce32d35f | 249 | #if defined(CRT_GET_RFIB_TEXT) || defined(CRT_GET_RFIB_DATA) |
250 | /* If we used the new __register_frame_info_bases interface, | |
251 | make sure that we deregister from the same place. */ | |
252 | if (__deregister_frame_info_bases) | |
253 | __deregister_frame_info_bases (__EH_FRAME_BEGIN__); | |
254 | #else | |
ee055d40 | 255 | if (__deregister_frame_info) |
256 | __deregister_frame_info (__EH_FRAME_BEGIN__); | |
d757b8c9 | 257 | #endif |
ce32d35f | 258 | #endif |
259 | ||
dade0711 | 260 | completed = 1; |
b7c87ff2 | 261 | } |
262 | ||
dade0711 | 263 | |
b7c87ff2 | 264 | /* Stick a call to __do_global_dtors_aux into the .fini section. */ |
a92771b8 | 265 | |
ebd9163c | 266 | static void __attribute__ ((__unused__)) |
aedb00bf | 267 | fini_dummy (void) |
b7c87ff2 | 268 | { |
269 | asm (FINI_SECTION_ASM_OP); | |
a815e00c | 270 | CRT_CALL_STATIC_FUNCTION (__do_global_dtors_aux); |
b7c87ff2 | 271 | #ifdef FORCE_FINI_SECTION_ALIGN |
272 | FORCE_FINI_SECTION_ALIGN; | |
273 | #endif | |
274 | asm (TEXT_SECTION_ASM_OP); | |
275 | } | |
276 | ||
f313c0e1 | 277 | #if defined(EH_FRAME_SECTION_NAME) || defined(JCR_SECTION_NAME) |
c4fa4c4d | 278 | /* Stick a call to __register_frame_info into the .init section. For some |
279 | reason calls with no arguments work more reliably in .init, so stick the | |
280 | call in another function. */ | |
d757b8c9 | 281 | |
282 | static void | |
aedb00bf | 283 | frame_dummy (void) |
d757b8c9 | 284 | { |
f313c0e1 | 285 | #ifdef EH_FRAME_SECTION_NAME |
ad87de1e | 286 | static struct object object; |
f6338f42 | 287 | #if defined(CRT_GET_RFIB_TEXT) || defined(CRT_GET_RFIB_DATA) |
288 | void *tbase, *dbase; | |
289 | #ifdef CRT_GET_RFIB_TEXT | |
290 | CRT_GET_RFIB_TEXT (tbase); | |
291 | #else | |
292 | tbase = 0; | |
293 | #endif | |
294 | #ifdef CRT_GET_RFIB_DATA | |
295 | CRT_GET_RFIB_DATA (dbase); | |
296 | #else | |
297 | dbase = 0; | |
298 | #endif | |
299 | if (__register_frame_info_bases) | |
300 | __register_frame_info_bases (__EH_FRAME_BEGIN__, &object, tbase, dbase); | |
301 | #else | |
ee055d40 | 302 | if (__register_frame_info) |
303 | __register_frame_info (__EH_FRAME_BEGIN__, &object); | |
f6338f42 | 304 | #endif |
f313c0e1 | 305 | #endif /* EH_FRAME_SECTION_NAME */ |
306 | #ifdef JCR_SECTION_NAME | |
307 | if (__JCR_LIST__[0] && _Jv_RegisterClasses) | |
308 | _Jv_RegisterClasses (__JCR_LIST__); | |
309 | #endif /* JCR_SECTION_NAME */ | |
d757b8c9 | 310 | } |
311 | ||
ebd9163c | 312 | static void __attribute__ ((__unused__)) |
aedb00bf | 313 | init_dummy (void) |
d757b8c9 | 314 | { |
315 | asm (INIT_SECTION_ASM_OP); | |
a815e00c | 316 | CRT_CALL_STATIC_FUNCTION (frame_dummy); |
d757b8c9 | 317 | #ifdef FORCE_INIT_SECTION_ALIGN |
318 | FORCE_INIT_SECTION_ALIGN; | |
319 | #endif | |
320 | asm (TEXT_SECTION_ASM_OP); | |
321 | } | |
f313c0e1 | 322 | #endif /* EH_FRAME_SECTION_NAME || JCR_SECTION_NAME */ |
d757b8c9 | 323 | |
b7c87ff2 | 324 | #else /* OBJECT_FORMAT_ELF */ |
325 | ||
b13ae905 | 326 | /* The function __do_global_ctors_aux is compiled twice (once in crtbegin.o |
d8fa92ab | 327 | and once in crtend.o). It must be declared static to avoid a link |
b13ae905 | 328 | error. Here, we define __do_global_ctors as an externally callable |
329 | function. It is externally callable so that __main can invoke it when | |
330 | INVOKE__main is defined. This has the additional effect of forcing cc1 | |
331 | to switch to the .text section. */ | |
a92771b8 | 332 | |
205b5771 | 333 | static void __do_global_ctors_aux (void); |
aedb00bf | 334 | void |
335 | __do_global_ctors (void) | |
84b64a19 | 336 | { |
584907e7 | 337 | #ifdef INVOKE__main |
338 | /* If __main won't actually call __do_global_ctors then it doesn't matter | |
339 | what's inside the function. The inside of __do_global_ctors_aux is | |
340 | called automatically in that case. And the Alliant fx2800 linker | |
341 | crashes on this reference. So prevent the crash. */ | |
84b64a19 | 342 | __do_global_ctors_aux (); |
343 | #endif | |
344 | } | |
9d13f5c4 | 345 | |
346 | asm (INIT_SECTION_ASM_OP); /* cc1 doesn't know that we are switching! */ | |
347 | ||
3c67709e | 348 | /* On some svr4 systems, the initial .init section preamble code provided in |
349 | crti.o may do something, such as bump the stack, which we have to | |
350 | undo before we reach the function prologue code for __do_global_ctors | |
351 | (directly below). For such systems, define the macro INIT_SECTION_PREAMBLE | |
a92771b8 | 352 | to expand into the code needed to undo the actions of the crti.o file. */ |
3c67709e | 353 | |
354 | #ifdef INIT_SECTION_PREAMBLE | |
355 | INIT_SECTION_PREAMBLE; | |
356 | #endif | |
357 | ||
9d13f5c4 | 358 | /* A routine to invoke all of the global constructors upon entry to the |
359 | program. We put this into the .init section (for systems that have | |
360 | such a thing) so that we can properly perform the construction of | |
361 | file-scope static-storage C++ objects within shared libraries. */ | |
362 | ||
363 | static void | |
aedb00bf | 364 | __do_global_ctors_aux (void) /* prologue goes in .init section */ |
9d13f5c4 | 365 | { |
635d52b7 | 366 | #ifdef FORCE_INIT_SECTION_ALIGN |
367 | FORCE_INIT_SECTION_ALIGN; /* Explicit align before switch to .text */ | |
368 | #endif | |
9d13f5c4 | 369 | asm (TEXT_SECTION_ASM_OP); /* don't put epilogue and body in .init */ |
370 | DO_GLOBAL_CTORS_BODY; | |
75d3a87b | 371 | atexit (__do_global_dtors); |
9d13f5c4 | 372 | } |
373 | ||
b7c87ff2 | 374 | #endif /* OBJECT_FORMAT_ELF */ |
8313a782 | 375 | |
584907e7 | 376 | #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */ |
8313a782 | 377 | |
378 | /* This case is used by the Irix 6 port, which supports named sections but | |
379 | not an SVR4-style .fini section. __do_global_dtors can be non-static | |
d757b8c9 | 380 | in this case because we protect it with -hidden_symbol. */ |
381 | ||
8313a782 | 382 | void |
aedb00bf | 383 | __do_global_dtors (void) |
8313a782 | 384 | { |
f6338f42 | 385 | func_ptr *p, f; |
386 | for (p = __DTOR_LIST__ + 1; (f = *p); p++) | |
387 | f (); | |
d757b8c9 | 388 | |
2cb4ac60 | 389 | #ifdef EH_FRAME_SECTION_NAME |
ee055d40 | 390 | if (__deregister_frame_info) |
391 | __deregister_frame_info (__EH_FRAME_BEGIN__); | |
d757b8c9 | 392 | #endif |
8313a782 | 393 | } |
72ac783d | 394 | |
f313c0e1 | 395 | #if defined(EH_FRAME_SECTION_NAME) || defined(JCR_SECTION_NAME) |
584907e7 | 396 | /* A helper function for __do_global_ctors, which is in crtend.o. Here |
397 | in crtbegin.o, we can reference a couple of symbols not visible there. | |
398 | Plus, since we're before libgcc.a, we have no problems referencing | |
399 | functions from there. */ | |
72ac783d | 400 | void |
584907e7 | 401 | __do_global_ctors_1(void) |
72ac783d | 402 | { |
f313c0e1 | 403 | #ifdef EH_FRAME_SECTION_NAME |
72ac783d | 404 | static struct object object; |
ee055d40 | 405 | if (__register_frame_info) |
406 | __register_frame_info (__EH_FRAME_BEGIN__, &object); | |
b13ae905 | 407 | #endif |
2cee371f | 408 | #ifdef JCR_SECTION_NAME |
f313c0e1 | 409 | if (__JCR_LIST__[0] && _Jv_RegisterClasses) |
410 | _Jv_RegisterClasses (__JCR_LIST__); | |
411 | #endif | |
412 | } | |
413 | #endif /* EH_FRAME_SECTION_NAME || JCR_SECTION_NAME */ | |
2cee371f | 414 | |
584907e7 | 415 | #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */ |
416 | #error "What are you doing with crtstuff.c, then?" | |
417 | #endif | |
418 | ||
419 | #elif defined(CRT_END) /* ! CRT_BEGIN */ | |
420 | ||
421 | /* Put a word containing zero at the end of each of our two lists of function | |
422 | addresses. Note that the words defined here go into the .ctors and .dtors | |
423 | sections of the crtend.o file, and since that file is always linked in | |
424 | last, these words naturally end up at the very ends of the two lists | |
425 | contained in these two sections. */ | |
426 | ||
427 | #ifdef CTOR_LIST_END | |
428 | CTOR_LIST_END; | |
429 | #elif defined(CTORS_SECTION_ASM_OP) | |
430 | /* Hack: force cc1 to switch to .data section early, so that assembling | |
431 | __CTOR_LIST__ does not undo our behind-the-back change to .ctors. */ | |
432 | static func_ptr force_to_data[1] __attribute__ ((__unused__)) = { }; | |
433 | asm (CTORS_SECTION_ASM_OP); | |
434 | STATIC func_ptr __CTOR_END__[1] | |
435 | __attribute__((aligned(sizeof(func_ptr)))) | |
436 | = { (func_ptr) 0 }; | |
437 | #else | |
438 | STATIC func_ptr __CTOR_END__[1] | |
439 | __attribute__((section(".ctors"), aligned(sizeof(func_ptr)))) | |
440 | = { (func_ptr) 0 }; | |
441 | #endif | |
442 | ||
443 | #ifdef DTOR_LIST_END | |
444 | DTOR_LIST_END; | |
445 | #elif defined(DTORS_SECTION_ASM_OP) | |
446 | asm (DTORS_SECTION_ASM_OP); | |
447 | STATIC func_ptr __DTOR_END__[1] | |
448 | __attribute__ ((unused, aligned(sizeof(func_ptr)))) | |
449 | = { (func_ptr) 0 }; | |
450 | #else | |
451 | STATIC func_ptr __DTOR_END__[1] | |
452 | __attribute__((unused, section(".dtors"), aligned(sizeof(func_ptr)))) | |
453 | = { (func_ptr) 0 }; | |
454 | #endif | |
9d13f5c4 | 455 | |
584907e7 | 456 | #ifdef EH_FRAME_SECTION_NAME |
457 | /* Terminate the frame unwind info section with a 4byte 0 as a sentinel; | |
458 | this would be the 'length' field in a real FDE. */ | |
459 | STATIC int __FRAME_END__[] | |
460 | __attribute__ ((unused, mode(SI), section(EH_FRAME_SECTION_NAME), | |
461 | aligned(4))) | |
462 | = { 0 }; | |
463 | #endif /* EH_FRAME_SECTION */ | |
464 | ||
465 | #ifdef JCR_SECTION_NAME | |
466 | /* Null terminate the .jcr section array. */ | |
467 | STATIC void *__JCR_END__[1] | |
468 | __attribute__ ((unused, section(JCR_SECTION_NAME), | |
469 | aligned(sizeof(void *)))) | |
470 | = { 0 }; | |
471 | #endif /* JCR_SECTION_NAME */ | |
9d13f5c4 | 472 | |
473 | #ifdef INIT_SECTION_ASM_OP | |
474 | ||
b7c87ff2 | 475 | #ifdef OBJECT_FORMAT_ELF |
9d13f5c4 | 476 | |
b7c87ff2 | 477 | static void |
aedb00bf | 478 | __do_global_ctors_aux (void) |
b7c87ff2 | 479 | { |
480 | func_ptr *p; | |
481 | for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--) | |
482 | (*p) (); | |
483 | } | |
484 | ||
485 | /* Stick a call to __do_global_ctors_aux into the .init section. */ | |
a92771b8 | 486 | |
ebd9163c | 487 | static void __attribute__ ((__unused__)) |
aedb00bf | 488 | init_dummy (void) |
b7c87ff2 | 489 | { |
490 | asm (INIT_SECTION_ASM_OP); | |
a815e00c | 491 | CRT_CALL_STATIC_FUNCTION (__do_global_ctors_aux); |
b7c87ff2 | 492 | #ifdef FORCE_INIT_SECTION_ALIGN |
493 | FORCE_INIT_SECTION_ALIGN; | |
494 | #endif | |
495 | asm (TEXT_SECTION_ASM_OP); | |
e9bc07ed | 496 | #ifdef CRT_END_INIT_DUMMY |
497 | CRT_END_INIT_DUMMY; | |
baf8c510 | 498 | #endif |
b7c87ff2 | 499 | } |
500 | ||
501 | #else /* OBJECT_FORMAT_ELF */ | |
502 | ||
503 | /* Stick the real initialization code, followed by a normal sort of | |
504 | function epilogue at the very end of the .init section for this | |
505 | entire root executable file or for this entire shared library file. | |
506 | ||
507 | Note that we use some tricks here to get *just* the body and just | |
508 | a function epilogue (but no function prologue) into the .init | |
c3418f42 | 509 | section of the crtend.o file. Specifically, we switch to the .text |
b7c87ff2 | 510 | section, start to define a function, and then we switch to the .init |
511 | section just before the body code. | |
512 | ||
513 | Earlier on, we put the corresponding function prologue into the .init | |
514 | section of the crtbegin.o file (which will be linked in first). | |
515 | ||
516 | Note that we want to invoke all constructors for C++ file-scope static- | |
517 | storage objects AFTER any other possible initialization actions which | |
518 | may be performed by the code in the .init section contributions made by | |
519 | other libraries, etc. That's because those other initializations may | |
520 | include setup operations for very primitive things (e.g. initializing | |
521 | the state of the floating-point coprocessor, etc.) which should be done | |
a92771b8 | 522 | before we start to execute any of the user's code. */ |
9d13f5c4 | 523 | |
524 | static void | |
aedb00bf | 525 | __do_global_ctors_aux (void) /* prologue goes in .text section */ |
9d13f5c4 | 526 | { |
527 | asm (INIT_SECTION_ASM_OP); | |
528 | DO_GLOBAL_CTORS_BODY; | |
75d3a87b | 529 | atexit (__do_global_dtors); |
997d68fe | 530 | } /* epilogue and body go in .init section */ |
531 | ||
220345e0 | 532 | #ifdef FORCE_INIT_SECTION_ALIGN |
997d68fe | 533 | FORCE_INIT_SECTION_ALIGN; |
220345e0 | 534 | #endif |
997d68fe | 535 | |
536 | asm (TEXT_SECTION_ASM_OP); | |
9d13f5c4 | 537 | |
b7c87ff2 | 538 | #endif /* OBJECT_FORMAT_ELF */ |
539 | ||
584907e7 | 540 | #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */ |
8313a782 | 541 | |
542 | /* This case is used by the Irix 6 port, which supports named sections but | |
543 | not an SVR4-style .init section. __do_global_ctors can be non-static | |
d757b8c9 | 544 | in this case because we protect it with -hidden_symbol. */ |
584907e7 | 545 | extern void __do_global_ctors_1(void); |
8313a782 | 546 | void |
aedb00bf | 547 | __do_global_ctors (void) |
8313a782 | 548 | { |
549 | func_ptr *p; | |
47cff348 | 550 | #if defined(EH_FRAME_SECTION_NAME) || defined(JCR_SECTION_NAME) |
584907e7 | 551 | __do_global_ctors_1(); |
d757b8c9 | 552 | #endif |
8313a782 | 553 | for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--) |
554 | (*p) (); | |
555 | } | |
b7c87ff2 | 556 | |
584907e7 | 557 | #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */ |
558 | #error "What are you doing with crtstuff.c, then?" | |
b13ae905 | 559 | #endif |
9d13f5c4 | 560 | |
584907e7 | 561 | #else /* ! CRT_BEGIN && ! CRT_END */ |
562 | #error "One of CRT_BEGIN or CRT_END must be defined." | |
b13ae905 | 563 | #endif |
9d13f5c4 | 564 | |
5c61dffd | 565 | #else /* OBJECT_FORMAT_MACHO */ |
566 | ||
567 | /* For Mach-O format executables, we assume that the system's runtime is | |
568 | smart enough to handle constructors and destructors, but doesn't have | |
569 | an init section (if it can't even handle constructors/destructors | |
570 | you should be using INVOKE__main, not crtstuff). All we need to do | |
571 | is install/deinstall the frame information for exceptions. We do this | |
572 | by putting a constructor in crtbegin.o and a destructor in crtend.o. | |
573 | ||
574 | crtend.o also puts in the terminating zero in the frame information | |
2c0e001b | 575 | segment. */ |
5c61dffd | 576 | |
577 | /* The crtstuff for other object formats use the symbol __EH_FRAME_BEGIN__ | |
578 | to figure out the start of the exception frame, but here we use | |
579 | getsectbynamefromheader to find this value. Either method would work, | |
580 | but this method avoids creating any global symbols, which seems | |
2c0e001b | 581 | cleaner. */ |
5c61dffd | 582 | |
583 | #include <mach-o/ldsyms.h> | |
584 | extern const struct section * | |
585 | getsectbynamefromheader (const struct mach_header *, | |
586 | const char *, const char *); | |
587 | ||
588 | #ifdef CRT_BEGIN | |
589 | ||
205b5771 | 590 | static void __reg_frame_ctor (void) __attribute__ ((constructor)); |
5c61dffd | 591 | |
592 | static void | |
aedb00bf | 593 | __reg_frame_ctor (void) |
5c61dffd | 594 | { |
595 | static struct object object; | |
596 | const struct section *eh_frame; | |
597 | ||
598 | eh_frame = getsectbynamefromheader (&_mh_execute_header, | |
599 | "__TEXT", "__eh_frame"); | |
600 | __register_frame_info ((void *) eh_frame->addr, &object); | |
601 | } | |
602 | ||
584907e7 | 603 | #elif defined(CRT_END) |
5c61dffd | 604 | |
205b5771 | 605 | static void __dereg_frame_dtor (void) __attribute__ ((destructor)); |
5c61dffd | 606 | |
205b5771 | 607 | static void |
aedb00bf | 608 | __dereg_frame_dtor (void) |
5c61dffd | 609 | { |
610 | const struct section *eh_frame; | |
611 | ||
612 | eh_frame = getsectbynamefromheader (&_mh_execute_header, | |
613 | "__TEXT", "__eh_frame"); | |
614 | __deregister_frame_info ((void *) eh_frame->addr); | |
615 | } | |
616 | ||
2c0e001b | 617 | /* Terminate the frame section with a final zero. */ |
2cb4ac60 | 618 | STATIC int __FRAME_END__[] |
5ce1fa41 | 619 | __attribute__ ((unused, mode(SI), section(EH_FRAME_SECTION_NAME), |
620 | aligned(4))) | |
2cb4ac60 | 621 | = { 0 }; |
584907e7 | 622 | |
623 | #else /* ! CRT_BEGIN && ! CRT_END */ | |
624 | #error "One of CRT_BEGIN or CRT_END must be defined." | |
625 | #endif | |
5c61dffd | 626 | |
627 | #endif /* OBJECT_FORMAT_MACHO */ |