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
   6    Written by Ron Guilmette (rfg@netcom.com)
   7
   8 Copyright (C) 1991 Free Software Foundation, Inc.
   9
  10 This file is part of GNU CC.
  11
  12 GNU CC is free software; you can redistribute it and/or modify
  13 it under the terms of the GNU General Public License as published by
  14 the Free Software Foundation; either version 2, or (at your option)
  15 any later version.
  16
  17 GNU CC is distributed in the hope that it will be useful,
  18 but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 GNU General Public License for more details.
  21
  22 You should have received a copy of the GNU General Public License
  23 along with GNU CC; see the file COPYING.  If not, write to
  24 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, 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 HAVE_ATEXIT
  35 extern void atexit (void (*) (void));
  36 #define ON_EXIT(FUNC,ARG) atexit ((FUNC))
  37 #else
  38 #ifdef sun
  39 extern void on_exit (void*, void*);
  40 #define ON_EXIT(FUNC,ARG) on_exit ((FUNC), (ARG))
  41 #endif
  42 #endif
  43
  44 /*  Declare a pointer to void function type.  */
  45
  46 typedef void (*func_ptr) (void);
  47
  48 /* Declare the set of symbols use as begin and end markers for the lists
  49    of global object constructors and global object destructors.  */
  50
  51 extern func_ptr __CTOR_LIST__[];
  52 extern func_ptr __DTOR_LIST__[];
  53
  54 /* Declare the routine which need to get invoked at program exit time.  */
  55
  56 extern void __do_global_dtors ();
  57
  58 /* Define a macro with the code which needs to be executed at program
  59    start-up time.  This macro is used in two places in crtstuff.c (for
  60    systems which support a .init section) and in one place in libgcc2.c
  61    (for those system which do *not* support a .init section).  For all
  62    three places where this code might appear, it must be identical, so
  63    we define it once here as a macro to avoid various instances getting
  64    out-of-sync with one another.  */
  65
  66 /* Some systems place the number of pointers
  67    in the first word of the table.
  68    On other systems, that word is -1.
  69    In all cases, the table is null-terminated.
  70    If the length is not recorded, count up to the null.  */
  71
  72 /* Some systems use a different strategy for finding the ctors.
  73    For example, svr3.  */
  74 #ifndef DO_GLOBAL_CTORS_BODY
  75 #define DO_GLOBAL_CTORS_BODY                                            \
  76 do {                                                                    \
  77   unsigned long nptrs = (unsigned long) __CTOR_LIST__[0];               \
  78   unsigned i;                                                           \
  79   if (nptrs == -1)                                                      \
  80     for (nptrs = 0; __CTOR_LIST__[nptrs + 1] != 0; nptrs++);            \
  81   for (i = nptrs; i >= 1; i--)                                          \
  82     __CTOR_LIST__[i] ();                                                \
  83 } while (0)
  84 #endif
  85