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, 2000
   6    Free Software Foundation, Inc.
   7    Contributed by Ron Guilmette (rfg@segfault.us.com)
   8
   9 This file is part of GNU CC.
  10
  11 GNU CC is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU General Public License as published by
  13 the Free Software Foundation; either version 2, or (at your option)
  14 any later version.
  15
  16 GNU CC is distributed in the hope that it will be useful,
  17 but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 GNU General Public License for more details.
  20
  21 You should have received a copy of the GNU General Public License
  22 along with GNU CC; see the file COPYING.  If not, write to
  23 the Free Software Foundation, 59 Temple Place - Suite 330,
  24 Boston, MA 02111-1307, USA.  */
  25
  26 /*      This file contains definitions and declarations of things
  27         relating to the normal start-up-time invocation of C++
  28         file-scope static object constructors.  These declarations
  29         and definitions are used by *both* libgcc2.c and by crtstuff.c.
  30
  31         Note that this file should only be compiled with GCC.
  32 */
  33
  34 #ifdef NEED_ATEXIT
  35 extern int atexit (void (*) (void));
  36 #endif
  37
  38 /*  Declare a pointer to void function type.  */
  39
  40 typedef void (*func_ptr) (void);
  41
  42 /* Declare the set of symbols use as begin and end markers for the lists
  43    of global object constructors and global object destructors.  */
  44
  45 extern func_ptr __CTOR_LIST__[];
  46 extern func_ptr __DTOR_LIST__[];
  47
  48 /* Declare the routine which needs to get invoked at program start time.  */
  49
  50 extern void __do_global_ctors (void);
  51
  52 /* Declare the routine which needs to get invoked at program exit time.  */
  53
  54 extern void __do_global_dtors (void);
  55
  56 /* Define a macro with the code which needs to be executed at program
  57    start-up time.  This macro is used in two places in crtstuff.c (for
  58    systems which support a .init section) and in one place in libgcc2.c
  59    (for those system which do *not* support a .init section).  For all
  60    three places where this code might appear, it must be identical, so
  61    we define it once here as a macro to avoid various instances getting
  62    out-of-sync with one another.  */
  63
  64 /* Some systems place the number of pointers
  65    in the first word of the table.
  66    On other systems, that word is -1.
  67    In all cases, the table is null-terminated.
  68    If the length is not recorded, count up to the null.  */
  69
  70 /* Some systems use a different strategy for finding the ctors.
  71    For example, svr3.  */
  72 #ifndef DO_GLOBAL_CTORS_BODY
  73 #define DO_GLOBAL_CTORS_BODY                                            \
  74 do {                                                                    \
  75   unsigned long nptrs = (unsigned long) __CTOR_LIST__[0];               \
  76   unsigned i;                                                           \
  77   if (nptrs == (unsigned long)-1)                                       \
  78     for (nptrs = 0; __CTOR_LIST__[nptrs + 1] != 0; nptrs++);            \
  79   for (i = nptrs; i >= 1; i--)                                          \
  80     __CTOR_LIST__[i] ();                                                \
  81 } while (0)
  82 #endif
  83