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 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, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  23
  24 /*      This file contains definitions and declarations of things
  25         relating to the normal start-up-time invocation of C++
  26         file-scope static object constructors.  These declarations
  27         and definitions are used by *both* libgcc2.c and by crtstuff.c.
  28
  29         Note that this file should only be compiled with GCC.
  30 */
  31
  32 #ifdef HAVE_ATEXIT
  33 #ifdef WINNT
  34 extern int atexit (void (*) (void));
  35 #else
  36 extern void atexit (void (*) (void));
  37 #endif
  38 #define ON_EXIT(FUNC,ARG) atexit ((FUNC))
  39 #else
  40 #ifdef sun
  41 extern void on_exit (void*, void*);
  42 #define ON_EXIT(FUNC,ARG) on_exit ((FUNC), (ARG))
  43 #endif
  44 #endif
  45
  46 /*  Declare a pointer to void function type.  */
  47
  48 typedef void (*func_ptr) (void);
  49
  50 /* Declare the set of symbols use as begin and end markers for the lists
  51    of global object constructors and global object destructors.  */
  52
  53 extern func_ptr __CTOR_LIST__[];
  54 extern func_ptr __DTOR_LIST__[];
  55
  56 /* Declare the routine which need to get invoked at program exit time.  */
  57
  58 extern void __do_global_dtors ();
  59
  60 /* Define a macro with the code which needs to be executed at program
  61    start-up time.  This macro is used in two places in crtstuff.c (for
  62    systems which support a .init section) and in one place in libgcc2.c
  63    (for those system which do *not* support a .init section).  For all
  64    three places where this code might appear, it must be identical, so
  65    we define it once here as a macro to avoid various instances getting
  66    out-of-sync with one another.  */
  67
  68 /* Some systems place the number of pointers
  69    in the first word of the table.
  70    On other systems, that word is -1.
  71    In all cases, the table is null-terminated.
  72    If the length is not recorded, count up to the null.  */
  73
  74 /* Some systems use a different strategy for finding the ctors.
  75    For example, svr3.  */
  76 #ifndef DO_GLOBAL_CTORS_BODY
  77 #define DO_GLOBAL_CTORS_BODY                                            \
  78 do {                                                                    \
  79   unsigned long nptrs = (unsigned long) __CTOR_LIST__[0];               \
  80   unsigned i;                                                           \
  81   if (nptrs == -1)                                                      \
  82     for (nptrs = 0; __CTOR_LIST__[nptrs + 1] != 0; nptrs++);            \
  83   for (i = nptrs; i >= 1; i--)                                          \
  84     __CTOR_LIST__[i] ();                                                \
  85 } while (0)
  86 #endif
  87