lib/csu/common_elf/dwarf2_eh.h

   1 /*      $NetBSD: dwarf2_eh.h,v 1.2 2003/09/07 22:27:55 fvdl Exp $       */
   2
   3 /*-
   4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jason R. Thorpe.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*
  33  * Definitions for DWARF2 stack frame unwinding/exception handling.
  34  */
  35
  36 #ifdef __GNUC__
  37 /*
  38  * We must pass a DWARF2 unwind object to __register_frame_info().
  39  * Since we don't reference any members of this object, but rather
  40  * only provide storage for it, we just declare it in a simple,
  41  * dumb way.  We need room for 6 pointers in GCC 2.95.3 and GCC 3.0,
  42  * but declare it with a little slop at the end.
  43  */
  44 struct dwarf2_eh_object {
  45         void *space[8];
  46 };
  47
  48 /*
  49  * These routines are provided by libgcc to register/unregister
  50  * frame info.  Note these prototypes must generate weak references
  51  * (even though the routines in libgcc have strong definitions).
  52  * This is so that we can link with a libgcc that doesn't have these
  53  * routines (e.g. one that uses sjlj exceptions).
  54  */
  55
  56 /*
  57  * A few platforms (x86_64, s390) have read-only .eh_frame by default,
  58  * so they must have it declared 'const'. These platforms will override
  59  * __EH_FRAME_CONST (which is empty by default) in their CPP flags.
  60  */
  61
  62 #ifndef __EH_FRAME_CONST
  63 #define __EH_FRAME_CONST
  64 #endif
  65
  66 extern void __register_frame_info(__EH_FRAME_CONST void *,
  67     struct dwarf2_eh_object *) __attribute__((weak));
  68 extern void __deregister_frame_info(__EH_FRAME_CONST void *)
  69     __attribute__((weak));
  70 #endif /* __GNUC__ */