libgcc/crtstuff.c

   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).
   7
   8 This file is part of GCC.
   9
  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
  13 version.
  14
  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
  18 for more details.
  19
  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.
  23
  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/>.  */
  28
  29 /* This file is a bit like libgcc2.c in that it is compiled
  30    multiple times and yields multiple .o files.
  31
  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.
  38
  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.
  42
  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.)
  47
  48    This file must be compiled with gcc.  */
  49
  50 /* Target machine header files require this define. */
  51 #define IN_LIBGCC2
  52
  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"
  57 #undef pid_t
  58 #undef rlim_t
  59 #undef ssize_t
  60 #undef vfork
  61 #include "tconfig.h"
  62 #include "tsystem.h"
  63 #include "coretypes.h"
  64 #include "tm.h"
  65 #include "libgcc_tm.h"
  66 #include "unwind-dw2-fde.h"
  67
  68 #ifndef FORCE_CODE_SECTION_ALIGN
  69 # define FORCE_CODE_SECTION_ALIGN
  70 #endif
  71
  72 #ifndef CRT_CALL_STATIC_FUNCTION
  73 # define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC)     \
  74 static void __attribute__((__used__))                   \
  75 call_ ## FUNC (void)                                    \
  76 {                                                       \
  77   asm (SECTION_OP);                                     \
  78   FUNC ();                                              \
  79   FORCE_CODE_SECTION_ALIGN                              \
  80   asm (TEXT_SECTION_ASM_OP);                            \
  81 }
  82 #endif
  83
  84 #if defined(OBJECT_FORMAT_ELF) \
  85     && !defined(OBJECT_FORMAT_FLAT) \
  86     && defined(HAVE_LD_EH_FRAME_HDR) \
  87     && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
  88     && defined(__FreeBSD__) && __FreeBSD__ >= 7
  89 #include <link.h>
  90 # define USE_PT_GNU_EH_FRAME
  91 #endif
  92
  93 #if defined(OBJECT_FORMAT_ELF) \
  94     && !defined(OBJECT_FORMAT_FLAT) \
  95     && defined(HAVE_LD_EH_FRAME_HDR) && defined(TARGET_DL_ITERATE_PHDR) \
  96     && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
  97     && defined(__sun__) && defined(__svr4__)
  98 #include <link.h>
  99 # define USE_PT_GNU_EH_FRAME
 100 #endif
 101
 102 #if defined(OBJECT_FORMAT_ELF) \
 103     && !defined(OBJECT_FORMAT_FLAT) \
 104     && defined(HAVE_LD_EH_FRAME_HDR) \
 105     && !defined(inhibit_libc) && !defined(CRTSTUFFT_O) \
 106     && defined(__GLIBC__) && __GLIBC__ >= 2
 107 #include <link.h>
 108 /* uClibc pretends to be glibc 2.2 and DT_CONFIG is defined in its link.h.
 109    But it doesn't use PT_GNU_EH_FRAME ELF segment currently.  */
 110 # if !defined(__UCLIBC__) \
 111      && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
 112      || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
 113 #  define USE_PT_GNU_EH_FRAME
 114 # endif
 115 #endif
 116 #if defined(EH_FRAME_SECTION_NAME) && !defined(USE_PT_GNU_EH_FRAME)
 117 # define USE_EH_FRAME_REGISTRY
 118 #endif
 119 #if defined(EH_FRAME_SECTION_NAME) && EH_TABLES_CAN_BE_READ_ONLY
 120 # define EH_FRAME_SECTION_CONST const
 121 #else
 122 # define EH_FRAME_SECTION_CONST
 123 #endif
 124
 125 #if !defined(DTOR_LIST_END) && defined(OBJECT_FORMAT_ELF) \
 126     && defined(HAVE_GAS_HIDDEN) && !defined(FINI_ARRAY_SECTION_ASM_OP)
 127 # define HIDDEN_DTOR_LIST_END
 128 #endif
 129
 130 #if !defined(USE_TM_CLONE_REGISTRY) && defined(OBJECT_FORMAT_ELF)
 131 # define USE_TM_CLONE_REGISTRY 1
 132 #endif
 133
 134 /* We do not want to add the weak attribute to the declarations of these
 135    routines in unwind-dw2-fde.h because that will cause the definition of
 136    these symbols to be weak as well.
 137
 138    This exposes a core issue, how to handle creating weak references vs
 139    how to create weak definitions.  Either we have to have the definition
 140    of TARGET_WEAK_ATTRIBUTE be conditional in the shared header files or
 141    have a second declaration if we want a function's references to be weak,
 142    but not its definition.
 143
 144    Making TARGET_WEAK_ATTRIBUTE conditional seems like a good solution until
 145    one thinks about scaling to larger problems -- i.e., the condition under
 146    which TARGET_WEAK_ATTRIBUTE is active will eventually get far too
 147    complicated.
 148
 149    So, we take an approach similar to #pragma weak -- we have a second
 150    declaration for functions that we want to have weak references.
 151
 152    Neither way is particularly good.  */
 153
 154 /* References to __register_frame_info and __deregister_frame_info should
 155    be weak in this file if at all possible.  */
 156 extern void __register_frame_info (const void *, struct object *)
 157                                   TARGET_ATTRIBUTE_WEAK;
 158 extern void __register_frame_info_bases (const void *, struct object *,
 159                                          void *, void *)
 160                                   TARGET_ATTRIBUTE_WEAK;
 161 extern void *__deregister_frame_info (const void *)
 162                                      TARGET_ATTRIBUTE_WEAK;
 163 extern void *__deregister_frame_info_bases (const void *)
 164                                      TARGET_ATTRIBUTE_WEAK;
 165 extern void __do_global_ctors_1 (void);
 166
 167 /* Likewise for _Jv_RegisterClasses.  */
 168 extern void _Jv_RegisterClasses (void *) TARGET_ATTRIBUTE_WEAK;
 169
 170 /* Likewise for transactional memory clone tables.  */
 171 extern void _ITM_registerTMCloneTable (void *, size_t) TARGET_ATTRIBUTE_WEAK;
 172 extern void _ITM_deregisterTMCloneTable (void *) TARGET_ATTRIBUTE_WEAK;
 173
 174 #ifdef OBJECT_FORMAT_ELF
 175
 176 /*  Declare a pointer to void function type.  */
 177 typedef void (*func_ptr) (void);
 178 #define STATIC static
 179
 180 #else  /* OBJECT_FORMAT_ELF */
 181
 182 #include "gbl-ctors.h"
 183
 184 #define STATIC
 185
 186 #endif /* OBJECT_FORMAT_ELF */
 187
 188 #ifdef CRT_BEGIN
 189
 190 /* NOTE:  In order to be able to support SVR4 shared libraries, we arrange
 191    to have one set of symbols { __CTOR_LIST__, __DTOR_LIST__, __CTOR_END__,
 192    __DTOR_END__ } per root executable and also one set of these symbols
 193    per shared library.  So in any given whole process image, we may have
 194    multiple definitions of each of these symbols.  In order to prevent
 195    these definitions from conflicting with one another, and in order to
 196    ensure that the proper lists are used for the initialization/finalization
 197    of each individual shared library (respectively), we give these symbols
 198    only internal (i.e. `static') linkage, and we also make it a point to
 199    refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__
 200    symbol in crtbegin.o, where they are defined.  */
 201
 202 /* No need for .ctors/.dtors section if linker can place them in
 203    .init_array/.fini_array section.  */
 204 #ifndef USE_INITFINI_ARRAY
 205 /* The -1 is a flag to __do_global_[cd]tors indicating that this table
 206    does not start with a count of elements.  */
 207 #ifdef CTOR_LIST_BEGIN
 208 CTOR_LIST_BEGIN;
 209 #elif defined(CTORS_SECTION_ASM_OP)
 210 /* Hack: force cc1 to switch to .data section early, so that assembling
 211    __CTOR_LIST__ does not undo our behind-the-back change to .ctors.  */
 212 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
 213 asm (CTORS_SECTION_ASM_OP);
 214 STATIC func_ptr __CTOR_LIST__[1]
 215   __attribute__ ((__used__, aligned(sizeof(func_ptr))))
 216   = { (func_ptr) (-1) };
 217 #else
 218 STATIC func_ptr __CTOR_LIST__[1]
 219   __attribute__ ((__used__, section(".ctors"), aligned(sizeof(func_ptr))))
 220   = { (func_ptr) (-1) };
 221 #endif /* __CTOR_LIST__ alternatives */
 222
 223 #ifdef DTOR_LIST_BEGIN
 224 DTOR_LIST_BEGIN;
 225 #elif defined(DTORS_SECTION_ASM_OP)
 226 asm (DTORS_SECTION_ASM_OP);
 227 STATIC func_ptr __DTOR_LIST__[1]
 228   __attribute__ ((aligned(sizeof(func_ptr))))
 229   = { (func_ptr) (-1) };
 230 #else
 231 STATIC func_ptr __DTOR_LIST__[1]
 232   __attribute__((section(".dtors"), aligned(sizeof(func_ptr))))
 233   = { (func_ptr) (-1) };
 234 #endif /* __DTOR_LIST__ alternatives */
 235 #endif /* USE_INITFINI_ARRAY */
 236
 237 #ifdef USE_EH_FRAME_REGISTRY
 238 /* Stick a label at the beginning of the frame unwind info so we can register
 239    and deregister it with the exception handling library code.  */
 240 STATIC EH_FRAME_SECTION_CONST char __EH_FRAME_BEGIN__[]
 241      __attribute__((section(EH_FRAME_SECTION_NAME), aligned(4)))
 242      = { };
 243 #endif /* USE_EH_FRAME_REGISTRY */
 244
 245 #ifdef JCR_SECTION_NAME
 246 /* Stick a label at the beginning of the java class registration info
 247    so we can register them properly.  */
 248 STATIC void *__JCR_LIST__[]
 249   __attribute__ ((used, section(JCR_SECTION_NAME), aligned(sizeof(void*))))
 250   = { };
 251 #endif /* JCR_SECTION_NAME */
 252
 253 #if USE_TM_CLONE_REGISTRY
 254 STATIC func_ptr __TMC_LIST__[]
 255   __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void*))))
 256   = { };
 257 # ifdef HAVE_GAS_HIDDEN
 258 extern func_ptr __TMC_END__[] __attribute__((__visibility__ ("hidden")));
 259 # endif
 260
 261 static inline void
 262 deregister_tm_clones (void)
 263 {
 264   void (*fn) (void *);
 265
 266 #ifdef HAVE_GAS_HIDDEN
 267   if (__TMC_END__ - __TMC_LIST__ == 0)
 268     return;
 269 #else
 270   if (__TMC_LIST__[0] == NULL)
 271     return;
 272 #endif
 273
 274   fn = _ITM_deregisterTMCloneTable;
 275   __asm ("" : "+r" (fn));
 276   if (fn)
 277     fn (__TMC_LIST__);
 278 }
 279
 280 static inline void
 281 register_tm_clones (void)
 282 {
 283   void (*fn) (void *, size_t);
 284   size_t size;
 285
 286 #ifdef HAVE_GAS_HIDDEN
 287   size = (__TMC_END__ - __TMC_LIST__) / 2;
 288 #else
 289   for (size = 0; __TMC_LIST__[size * 2] != NULL; size++)
 290     continue;
 291 #endif
 292   if (size == 0)
 293     return;
 294
 295   fn = _ITM_registerTMCloneTable;
 296   __asm ("" : "+r" (fn));
 297   if (fn)
 298     fn (__TMC_LIST__, size);
 299 }
 300 #endif /* USE_TM_CLONE_REGISTRY */
 301
 302 #if defined(INIT_SECTION_ASM_OP) || defined(INIT_ARRAY_SECTION_ASM_OP)
 303
 304 #ifdef OBJECT_FORMAT_ELF
 305
 306 /* Declare the __dso_handle variable.  It should have a unique value
 307    in every shared-object; in a main program its value is zero.  The
 308    object should in any case be protected.  This means the instance
 309    in one DSO or the main program is not used in another object.  The
 310    dynamic linker takes care of this.  */
 311
 312 #ifdef TARGET_LIBGCC_SDATA_SECTION
 313 extern void *__dso_handle __attribute__ ((__section__ (TARGET_LIBGCC_SDATA_SECTION)));
 314 #endif
 315 #ifdef HAVE_GAS_HIDDEN
 316 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
 317 #endif
 318 #ifdef CRTSTUFFS_O
 319 void *__dso_handle = &__dso_handle;
 320 #else
 321 void *__dso_handle = 0;
 322 #endif
 323
 324 /* The __cxa_finalize function may not be available so we use only a
 325    weak declaration.  */
 326 extern void __cxa_finalize (void *) TARGET_ATTRIBUTE_WEAK;
 327
 328 /* Run all the global destructors on exit from the program.  */
 329
 330 /* Some systems place the number of pointers in the first word of the
 331    table.  On SVR4 however, that word is -1.  In all cases, the table is
 332    null-terminated.  On SVR4, we start from the beginning of the list and
 333    invoke each per-compilation-unit destructor routine in order
 334    until we find that null.
 335
 336    Note that this function MUST be static.  There will be one of these
 337    functions in each root executable and one in each shared library, but
 338    although they all have the same code, each one is unique in that it
 339    refers to one particular associated `__DTOR_LIST__' which belongs to the
 340    same particular root executable or shared library file.
 341
 342    On some systems, this routine is run more than once from the .fini,
 343    when exit is called recursively, so we arrange to remember where in
 344    the list we left off processing, and we resume at that point,
 345    should we be re-invoked.  */
 346
 347 static void __attribute__((used))
 348 __do_global_dtors_aux (void)
 349 {
 350   static _Bool completed;
 351
 352   if (__builtin_expect (completed, 0))
 353     return;
 354
 355 #ifdef CRTSTUFFS_O
 356   if (__cxa_finalize)
 357     __cxa_finalize (__dso_handle);
 358 #endif
 359
 360 #ifdef FINI_ARRAY_SECTION_ASM_OP
 361   /* If we are using .fini_array then destructors will be run via that
 362      mechanism.  */
 363 #elif defined(HIDDEN_DTOR_LIST_END)
 364   {
 365     /* Safer version that makes sure only .dtors function pointers are
 366        called even if the static variable is maliciously changed.  */
 367     extern func_ptr __DTOR_END__[] __attribute__((visibility ("hidden")));
 368     static size_t dtor_idx;
 369     const size_t max_idx = __DTOR_END__ - __DTOR_LIST__ - 1;
 370     func_ptr f;
 371
 372     while (dtor_idx < max_idx)
 373       {
 374         f = __DTOR_LIST__[++dtor_idx];
 375         f ();
 376       }
 377   }
 378 #else /* !defined (FINI_ARRAY_SECTION_ASM_OP) */
 379   {
 380     static func_ptr *p = __DTOR_LIST__ + 1;
 381     func_ptr f;
 382
 383     while ((f = *p))
 384       {
 385         p++;
 386         f ();
 387       }
 388   }
 389 #endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
 390
 391 #if USE_TM_CLONE_REGISTRY
 392   deregister_tm_clones ();
 393 #endif /* USE_TM_CLONE_REGISTRY */
 394
 395 #ifdef USE_EH_FRAME_REGISTRY
 396 #ifdef CRT_GET_RFIB_DATA
 397   /* If we used the new __register_frame_info_bases interface,
 398      make sure that we deregister from the same place.  */
 399   if (__deregister_frame_info_bases)
 400     __deregister_frame_info_bases (__EH_FRAME_BEGIN__);
 401 #else
 402   if (__deregister_frame_info)
 403     __deregister_frame_info (__EH_FRAME_BEGIN__);
 404 #endif
 405 #endif
 406
 407   completed = 1;
 408 }
 409
 410 /* Stick a call to __do_global_dtors_aux into the .fini section.  */
 411 #ifdef FINI_SECTION_ASM_OP
 412 CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux)
 413 #elif defined (FINI_ARRAY_SECTION_ASM_OP)
 414 static func_ptr __do_global_dtors_aux_fini_array_entry[]
 415   __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr))))
 416   = { __do_global_dtors_aux };
 417 #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */
 418 static void __attribute__((used))
 419 __do_global_dtors_aux_1 (void)
 420 {
 421   atexit (__do_global_dtors_aux);
 422 }
 423 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_dtors_aux_1)
 424 #endif
 425
 426 #if defined(USE_EH_FRAME_REGISTRY) \
 427     || defined(JCR_SECTION_NAME) \
 428     || defined(USE_TM_CLONE_REGISTRY)
 429 /* Stick a call to __register_frame_info into the .init section.  For some
 430    reason calls with no arguments work more reliably in .init, so stick the
 431    call in another function.  */
 432
 433 static void __attribute__((used))
 434 frame_dummy (void)
 435 {
 436 #ifdef USE_EH_FRAME_REGISTRY
 437   static struct object object;
 438 #ifdef CRT_GET_RFIB_DATA
 439   void *tbase, *dbase;
 440   tbase = 0;
 441   CRT_GET_RFIB_DATA (dbase);
 442   if (__register_frame_info_bases)
 443     __register_frame_info_bases (__EH_FRAME_BEGIN__, &object, tbase, dbase);
 444 #else
 445   if (__register_frame_info)
 446     __register_frame_info (__EH_FRAME_BEGIN__, &object);
 447 #endif /* CRT_GET_RFIB_DATA */
 448 #endif /* USE_EH_FRAME_REGISTRY */
 449
 450 #ifdef JCR_SECTION_NAME
 451   if (__JCR_LIST__[0])
 452     {
 453       void (*register_classes) (void *) = _Jv_RegisterClasses;
 454       __asm ("" : "+r" (register_classes));
 455       if (register_classes)
 456         register_classes (__JCR_LIST__);
 457     }
 458 #endif /* JCR_SECTION_NAME */
 459
 460 #if USE_TM_CLONE_REGISTRY
 461   register_tm_clones ();
 462 #endif /* USE_TM_CLONE_REGISTRY */
 463 }
 464
 465 #ifdef INIT_SECTION_ASM_OP
 466 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, frame_dummy)
 467 #else /* defined(INIT_SECTION_ASM_OP) */
 468 static func_ptr __frame_dummy_init_array_entry[]
 469   __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr))))
 470   = { frame_dummy };
 471 #endif /* !defined(INIT_SECTION_ASM_OP) */
 472 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
 473
 474 #else  /* OBJECT_FORMAT_ELF */
 475
 476 /* The function __do_global_ctors_aux is compiled twice (once in crtbegin.o
 477    and once in crtend.o).  It must be declared static to avoid a link
 478    error.  Here, we define __do_global_ctors as an externally callable
 479    function.  It is externally callable so that __main can invoke it when
 480    INVOKE__main is defined.  This has the additional effect of forcing cc1
 481    to switch to the .text section.  */
 482
 483 static void __do_global_ctors_aux (void);
 484 void
 485 __do_global_ctors (void)
 486 {
 487 #ifdef INVOKE__main
 488   /* If __main won't actually call __do_global_ctors then it doesn't matter
 489      what's inside the function.  The inside of __do_global_ctors_aux is
 490      called automatically in that case.  And the Alliant fx2800 linker
 491      crashes on this reference.  So prevent the crash.  */
 492   __do_global_ctors_aux ();
 493 #endif
 494 }
 495
 496 asm (INIT_SECTION_ASM_OP);      /* cc1 doesn't know that we are switching! */
 497
 498 /* A routine to invoke all of the global constructors upon entry to the
 499    program.  We put this into the .init section (for systems that have
 500    such a thing) so that we can properly perform the construction of
 501    file-scope static-storage C++ objects within shared libraries.  */
 502
 503 static void __attribute__((used))
 504 __do_global_ctors_aux (void)    /* prologue goes in .init section */
 505 {
 506   FORCE_CODE_SECTION_ALIGN      /* explicit align before switch to .text */
 507   asm (TEXT_SECTION_ASM_OP);    /* don't put epilogue and body in .init */
 508   DO_GLOBAL_CTORS_BODY;
 509   atexit (__do_global_dtors);
 510 }
 511
 512 #endif /* OBJECT_FORMAT_ELF */
 513
 514 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
 515
 516 extern void __do_global_dtors (void);
 517
 518 /* This case is used by the Irix 6 port, which supports named sections but
 519    not an SVR4-style .fini section.  __do_global_dtors can be non-static
 520    in this case because we protect it with -hidden_symbol.  */
 521
 522 void
 523 __do_global_dtors (void)
 524 {
 525   func_ptr *p, f;
 526   for (p = __DTOR_LIST__ + 1; (f = *p); p++)
 527     f ();
 528
 529 #if USE_TM_CLONE_REGISTRY
 530   deregister_tm_clones ();
 531 #endif /* USE_TM_CLONE_REGISTRY */
 532
 533 #ifdef USE_EH_FRAME_REGISTRY
 534   if (__deregister_frame_info)
 535     __deregister_frame_info (__EH_FRAME_BEGIN__);
 536 #endif
 537 }
 538
 539 #if defined(USE_EH_FRAME_REGISTRY) \
 540     || defined(JCR_SECTION_NAME) \
 541     || defined(USE_TM_CLONE_REGISTRY)
 542 /* A helper function for __do_global_ctors, which is in crtend.o.  Here
 543    in crtbegin.o, we can reference a couple of symbols not visible there.
 544    Plus, since we're before libgcc.a, we have no problems referencing
 545    functions from there.  */
 546 void
 547 __do_global_ctors_1(void)
 548 {
 549 #ifdef USE_EH_FRAME_REGISTRY
 550   static struct object object;
 551   if (__register_frame_info)
 552     __register_frame_info (__EH_FRAME_BEGIN__, &object);
 553 #endif
 554
 555 #ifdef JCR_SECTION_NAME
 556   if (__JCR_LIST__[0])
 557     {
 558       void (*register_classes) (void *) = _Jv_RegisterClasses;
 559       __asm ("" : "+r" (register_classes));
 560       if (register_classes)
 561         register_classes (__JCR_LIST__);
 562     }
 563 #endif
 564
 565 #if USE_TM_CLONE_REGISTRY
 566   register_tm_clones ();
 567 #endif /* USE_TM_CLONE_REGISTRY */
 568 }
 569 #endif /* USE_EH_FRAME_REGISTRY || JCR_SECTION_NAME || USE_TM_CLONE_REGISTRY */
 570
 571 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
 572 #error "What are you doing with crtstuff.c, then?"
 573 #endif
 574
 575 #elif defined(CRT_END) /* ! CRT_BEGIN */
 576
 577 /* No need for .ctors/.dtors section if linker can place them in
 578    .init_array/.fini_array section.  */
 579 #ifndef USE_INITFINI_ARRAY
 580 /* Put a word containing zero at the end of each of our two lists of function
 581    addresses.  Note that the words defined here go into the .ctors and .dtors
 582    sections of the crtend.o file, and since that file is always linked in
 583    last, these words naturally end up at the very ends of the two lists
 584    contained in these two sections.  */
 585
 586 #ifdef CTOR_LIST_END
 587 CTOR_LIST_END;
 588 #elif defined(CTORS_SECTION_ASM_OP)
 589 /* Hack: force cc1 to switch to .data section early, so that assembling
 590    __CTOR_LIST__ does not undo our behind-the-back change to .ctors.  */
 591 static func_ptr force_to_data[1] __attribute__ ((__used__)) = { };
 592 asm (CTORS_SECTION_ASM_OP);
 593 STATIC func_ptr __CTOR_END__[1]
 594   __attribute__((aligned(sizeof(func_ptr))))
 595   = { (func_ptr) 0 };
 596 #else
 597 STATIC func_ptr __CTOR_END__[1]
 598   __attribute__((section(".ctors"), aligned(sizeof(func_ptr))))
 599   = { (func_ptr) 0 };
 600 #endif
 601
 602 #ifdef DTOR_LIST_END
 603 DTOR_LIST_END;
 604 #elif defined(HIDDEN_DTOR_LIST_END)
 605 #ifdef DTORS_SECTION_ASM_OP
 606 asm (DTORS_SECTION_ASM_OP);
 607 #endif
 608 func_ptr __DTOR_END__[1]
 609   __attribute__ ((used,
 610 #ifndef DTORS_SECTION_ASM_OP
 611                   section(".dtors"),
 612 #endif
 613                   aligned(sizeof(func_ptr)), visibility ("hidden")))
 614   = { (func_ptr) 0 };
 615 #elif defined(DTORS_SECTION_ASM_OP)
 616 asm (DTORS_SECTION_ASM_OP);
 617 STATIC func_ptr __DTOR_END__[1]
 618   __attribute__ ((used, aligned(sizeof(func_ptr))))
 619   = { (func_ptr) 0 };
 620 #else
 621 STATIC func_ptr __DTOR_END__[1]
 622   __attribute__((used, section(".dtors"), aligned(sizeof(func_ptr))))
 623   = { (func_ptr) 0 };
 624 #endif
 625 #endif /* USE_INITFINI_ARRAY */
 626
 627 #ifdef EH_FRAME_SECTION_NAME
 628 /* Terminate the frame unwind info section with a 4byte 0 as a sentinel;
 629    this would be the 'length' field in a real FDE.  */
 630 # if __INT_MAX__ == 2147483647
 631 typedef int int32;
 632 # elif __LONG_MAX__ == 2147483647
 633 typedef long int32;
 634 # elif __SHRT_MAX__ == 2147483647
 635 typedef short int32;
 636 # else
 637 #  error "Missing a 4 byte integer"
 638 # endif
 639 STATIC EH_FRAME_SECTION_CONST int32 __FRAME_END__[]
 640      __attribute__ ((used, section(EH_FRAME_SECTION_NAME),
 641                      aligned(sizeof(int32))))
 642      = { 0 };
 643 #endif /* EH_FRAME_SECTION_NAME */
 644
 645 #ifdef JCR_SECTION_NAME
 646 /* Null terminate the .jcr section array.  */
 647 STATIC void *__JCR_END__[1]
 648    __attribute__ ((used, section(JCR_SECTION_NAME),
 649                    aligned(sizeof(void *))))
 650    = { 0 };
 651 #endif /* JCR_SECTION_NAME */
 652
 653 #if USE_TM_CLONE_REGISTRY
 654 # ifndef HAVE_GAS_HIDDEN
 655 static
 656 # endif
 657 func_ptr __TMC_END__[]
 658   __attribute__((used, section(".tm_clone_table"), aligned(sizeof(void *))))
 659 # ifdef HAVE_GAS_HIDDEN
 660   __attribute__((__visibility__ ("hidden"))) = { };
 661 # else
 662   = { 0, 0 };
 663 # endif
 664 #endif /* USE_TM_CLONE_REGISTRY */
 665
 666 #ifdef INIT_ARRAY_SECTION_ASM_OP
 667
 668 /* If we are using .init_array, there is nothing to do.  */
 669
 670 #elif defined(INIT_SECTION_ASM_OP)
 671
 672 #ifdef OBJECT_FORMAT_ELF
 673 static void __attribute__((used))
 674 __do_global_ctors_aux (void)
 675 {
 676   func_ptr *p;
 677   for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
 678     (*p) ();
 679 }
 680
 681 /* Stick a call to __do_global_ctors_aux into the .init section.  */
 682 CRT_CALL_STATIC_FUNCTION (INIT_SECTION_ASM_OP, __do_global_ctors_aux)
 683 #else  /* OBJECT_FORMAT_ELF */
 684
 685 /* Stick the real initialization code, followed by a normal sort of
 686    function epilogue at the very end of the .init section for this
 687    entire root executable file or for this entire shared library file.
 688
 689    Note that we use some tricks here to get *just* the body and just
 690    a function epilogue (but no function prologue) into the .init
 691    section of the crtend.o file.  Specifically, we switch to the .text
 692    section, start to define a function, and then we switch to the .init
 693    section just before the body code.
 694
 695    Earlier on, we put the corresponding function prologue into the .init
 696    section of the crtbegin.o file (which will be linked in first).
 697
 698    Note that we want to invoke all constructors for C++ file-scope static-
 699    storage objects AFTER any other possible initialization actions which
 700    may be performed by the code in the .init section contributions made by
 701    other libraries, etc.  That's because those other initializations may
 702    include setup operations for very primitive things (e.g. initializing
 703    the state of the floating-point coprocessor, etc.) which should be done
 704    before we start to execute any of the user's code.  */
 705
 706 static void
 707 __do_global_ctors_aux (void)    /* prologue goes in .text section */
 708 {
 709   asm (INIT_SECTION_ASM_OP);
 710   DO_GLOBAL_CTORS_BODY;
 711   atexit (__do_global_dtors);
 712 }                               /* epilogue and body go in .init section */
 713
 714 FORCE_CODE_SECTION_ALIGN
 715 asm (TEXT_SECTION_ASM_OP);
 716
 717 #endif /* OBJECT_FORMAT_ELF */
 718
 719 #elif defined(HAS_INIT_SECTION) /* ! INIT_SECTION_ASM_OP */
 720
 721 extern void __do_global_ctors (void);
 722
 723 /* This case is used by the Irix 6 port, which supports named sections but
 724    not an SVR4-style .init section.  __do_global_ctors can be non-static
 725    in this case because we protect it with -hidden_symbol.  */
 726 void
 727 __do_global_ctors (void)
 728 {
 729   func_ptr *p;
 730 #if defined(USE_EH_FRAME_REGISTRY) \
 731     || defined(JCR_SECTION_NAME) \
 732     || defined(USE_TM_CLONE_REGISTRY)
 733   __do_global_ctors_1();
 734 #endif
 735   for (p = __CTOR_END__ - 1; *p != (func_ptr) -1; p--)
 736     (*p) ();
 737 }
 738
 739 #else /* ! INIT_SECTION_ASM_OP && ! HAS_INIT_SECTION */
 740 #error "What are you doing with crtstuff.c, then?"
 741 #endif
 742
 743 #else /* ! CRT_BEGIN && ! CRT_END */
 744 #error "One of CRT_BEGIN or CRT_END must be defined."
 745 #endif