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 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 #ifndef HAVE_ATEXIT
  35 #define HAVE_ATEXIT     1       /* Take it from libgcc2.c */
  36 #endif
  37 #endif
  38
  39 #ifdef HAVE_ATEXIT
  40 #if defined (WINNT) || defined (NEED_ATEXIT)
  41 extern int atexit (void (*) (void));
  42 #else
  43 extern void atexit (void (*) (void));
  44 #endif
  45 #define ON_EXIT(FUNC,ARG) atexit ((FUNC))
  46 #else
  47 #ifdef sun
  48 extern int on_exit (void *, void *);    /* The man page says it returns int. */
  49 #define ON_EXIT(FUNC,ARG) on_exit ((FUNC), (ARG))
  50 #endif
  51 #endif
  52
  53 /*  Declare a pointer to void function type.  */
  54
  55 typedef void (*func_ptr) (void);
  56
  57 /* Declare the set of symbols use as begin and end markers for the lists
  58    of global object constructors and global object destructors.  */
  59
  60 extern func_ptr __CTOR_LIST__[];
  61 extern func_ptr __DTOR_LIST__[];
  62
  63 /* Declare the routine which need to get invoked at program exit time.  */
  64
  65 extern void __do_global_dtors ();
  66
  67 /* Define a macro with the code which needs to be executed at program
  68    start-up time.  This macro is used in two places in crtstuff.c (for
  69    systems which support a .init section) and in one place in libgcc2.c
  70    (for those system which do *not* support a .init section).  For all
  71    three places where this code might appear, it must be identical, so
  72    we define it once here as a macro to avoid various instances getting
  73    out-of-sync with one another.  */
  74
  75 /* Some systems place the number of pointers
  76    in the first word of the table.
  77    On other systems, that word is -1.
  78    In all cases, the table is null-terminated.
  79    If the length is not recorded, count up to the null.  */
  80
  81 /* Some systems use a different strategy for finding the ctors.
  82    For example, svr3.  */
  83 #ifndef DO_GLOBAL_CTORS_BODY
  84 #define DO_GLOBAL_CTORS_BODY                                            \
  85 do {                                                                    \
  86   unsigned long nptrs = (unsigned long) __CTOR_LIST__[0];               \
  87   unsigned i;                                                           \
  88   if (nptrs == -1)                                                      \
  89     for (nptrs = 0; __CTOR_LIST__[nptrs + 1] != 0; nptrs++);            \
  90   for (i = nptrs; i >= 1; i--)                                          \
  91     __CTOR_LIST__[i] ();                                                \
  92 } while (0)
  93 #endif
  94