GDB: fix offsets for reading svr4 link map on x86_64-nacl

gdb/nacl-tdep.c

 /* Target-dependent code for NaCl.
 
    Copyright (C) 2001, 2003-2012 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
@@ skipping 53 matching lines @@
 }
 
 static CORE_ADDR
 amd64_nacl_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
 {
   CORE_ADDR sp;
   sp = frame_unwind_register_unsigned (this_frame, gdbarch_sp_regnum (gdbarch));
   return amd64_nacl_addr_bits_remove (gdbarch, sp);
 }
 
+struct link_map_offsets *
+amd64_nacl_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL)
+    {
+      lmp = &lmo;
+
+      lmo.r_version_offset = 0;
+      lmo.r_version_size = 4;
+      lmo.r_map_offset = 4;
+      lmo.r_brk_offset = 8;
+      /* Dynamic linker is in the normal list of shared objects.  */
+      lmo.r_ldsomap_offset = -1;
+
+      lmo.link_map_size = 24;
+      lmo.l_addr_offset = 0;
+      lmo.l_name_offset = 8;
+      lmo.l_ld_offset = 12;
+      lmo.l_next_offset = 16;
+      lmo.l_prev_offset = 20;
+    }
+
+  return lmp;
+}
+
 static void
 amd64_nacl_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   linux_init_abi (info, gdbarch);
   amd64_init_abi (info, gdbarch);
   tdep->tdesc = tdesc_amd64_linux;
   set_solib_svr4_fetch_link_map_offsets (gdbarch,
-                                         svr4_lp64_fetch_link_map_offsets);
+                                         amd64_nacl_fetch_link_map_offsets);
   nacl_init_abi (info, gdbarch);
 
   /* NaCl data model.
 
      WARNING! This might confuse a lot of code, as it uses
        if (set_gdbarch_ptr_bit (gdbarch) == <bits>)
      to distinguish between i386 and x86_64 (lame!).  Luckily, most of that
      code is about native debugging and syscalls, so it is not used for NaCl.
 
      TODO(eaeltsin): find better way to distinguish between i386 and x86_64!  */
@@ skipping 16 matching lines @@
 
 void
 _initialize_nacl_tdep (void)
 {
   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
                           GDB_OSABI_NACL, amd64_nacl_init_abi);
 
   gdbarch_register_osabi (bfd_arch_i386, 0,
                           GDB_OSABI_NACL, i386_nacl_init_abi);
 }