gdb/tm-sysv4.h

   1 /* Macro definitions for GDB on all SVR4 target systems.
   2    Copyright (C) 1991, 1992, Free Software Foundation, Inc.
   3    Written by Fred Fish at Cygnus Support (fnf@cygnus.com).
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #include "solib.h"      /* Support for shared libraries. */
  22
  23 /* For SVR4 shared libraries, each call to a library routine goes through
  24    a small piece of trampoline code in the ".init" section.  Although each
  25    of these fragments is labeled with the name of the routine being called,
  26    the gdb symbol reading code deliberately ignores them so it won't confuse
  27    them with the real functions.  It does however know about the label that
  28    precedes all of the fragments, which is "_init".  Thus when we lookup a
  29    function that corresponds to a PC value which is in one of the trampoline
  30    fragments, we'll appear to be in the function "_init".  The following
  31    macro will evaluate to nonzero when NAME is valid and matches "_init".
  32    The horribly ugly wait_for_inferior() routine uses this macro to detect
  33    when we have stepped into one of these fragments. */
  34
  35 #define IN_SOLIB_TRAMPOLINE(pc,name) ((name) && (STREQ ("_init", name)))
  36
  37 /* In SVR4 ELF files, the ABI defines (pg. 4-25) that "External C symbols
  38    have the same names in C, assembly code, and object files' symbol
  39    tables."  So... */
  40
  41 #undef  NAMES_HAVE_UNDERSCORE
  42
  43 /* It is unknown which, if any, SVR4 assemblers do not accept dollar signs
  44    in identifiers.  The default in G++ is to use dots instead, for all SVR4
  45    systems, so we make that our default also.  FIXME: There should be some
  46    way to get G++ to tell us what CPLUS_MARKER it is using, perhaps by
  47    stashing it in the debugging information as part of the name of an
  48    invented symbol ("gcc_cplus_marker$" for example). */
  49
  50 #undef CPLUS_MARKER
  51 #define CPLUS_MARKER '.'