gcc/gbl-ctors.h

   1 /* Definitions relating to the special __do_global_init function used
   2    for getting g++ file-scope static objects constructed.  This file
   3    will get included either by libgcc2.c (for systems that don't support
   4    a .init section) or by crtstuff.c (for those that do).
   5    Copyright (C) 1991, 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
   6    Contributed by Ron Guilmette (rfg@segfault.us.com)
   7
   8 This file is part of GNU CC.
   9
  10 GNU CC is free software; you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation; either version 2, or (at your option)
  13 any later version.
  14
  15 GNU CC is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU CC; see the file COPYING.  If not, write to
  22 the Free Software Foundation, 59 Temple Place - Suite 330,
  23 Boston, MA 02111-1307, USA.  */
  24
  25 /*      This file contains definitions and declarations of things
  26         relating to the normal start-up-time invocation of C++
  27         file-scope static object constructors.  These declarations
  28         and definitions are used by *both* libgcc2.c and by crtstuff.c.
  29
  30         Note that this file should only be compiled with GCC.
  31 */
  32
  33 #ifdef NEED_ATEXIT
  34 extern int atexit (void (*) (void));
  35 #endif
  36
  37 /*  Declare a pointer to void function type.  */
  38
  39 typedef void (*func_ptr) (void);
  40
  41 /* Declare the set of symbols use as begin and end markers for the lists
  42    of global object constructors and global object destructors.  */
  43
  44 extern func_ptr __CTOR_LIST__[];
  45 extern func_ptr __DTOR_LIST__[];
  46
  47 /* Declare the routine which need to get invoked at program exit time.  */
  48
  49 extern void __do_global_dtors (void);
  50
  51 /* Define a macro with the code which needs to be executed at program
  52    start-up time.  This macro is used in two places in crtstuff.c (for
  53    systems which support a .init section) and in one place in libgcc2.c
  54    (for those system which do *not* support a .init section).  For all
  55    three places where this code might appear, it must be identical, so
  56    we define it once here as a macro to avoid various instances getting
  57    out-of-sync with one another.  */
  58
  59 /* Some systems place the number of pointers
  60    in the first word of the table.
  61    On other systems, that word is -1.
  62    In all cases, the table is null-terminated.
  63    If the length is not recorded, count up to the null.  */
  64
  65 /* Some systems use a different strategy for finding the ctors.
  66    For example, svr3.  */
  67 #ifndef DO_GLOBAL_CTORS_BODY
  68 #define DO_GLOBAL_CTORS_BODY                                            \
  69 do {                                                                    \
  70   unsigned long nptrs = (unsigned long) __CTOR_LIST__[0];               \
  71   unsigned i;                                                           \
  72   if (nptrs == (unsigned long)-1)                                       \
  73     for (nptrs = 0; __CTOR_LIST__[nptrs + 1] != 0; nptrs++);            \
  74   for (i = nptrs; i >= 1; i--)                                          \
  75     __CTOR_LIST__[i] ();                                                \
  76 } while (0)
  77 #endif
  78