Recognize NaCl OS ABI for all ELF files.

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 18 matching lines @@
 #include "osabi.h"
 #include "disasm.h"
 #include "breakpoint.h"
 #include "target.h"
 #include "elf-bfd.h"
 #include "inferior.h"
 
 static enum gdb_osabi
 nacl_osabi_sniffer (bfd *abfd)
 {
-  /* WARNING! This way of checking for NaCl OS ABI is deprecated.
-     See http://code.google.com/p/nativeclient/issues/detail?id=2971  */
-  if (bfd_get_flavour (abfd) == bfd_target_elf_flavour &&
-      elf_elfheader (abfd)->e_ident[EI_OSABI] == 123)
+  /* We removed Linux remote debugging support from NaCl debugger, so we must
+     handle all ELF files ourselves now.
+
+     If we want to support both Linux and NaCl remote debugging simultaneously,
+     we would have to find some way to distinguish NaCl and Linux binaries here.
+     Currently there is no way to distinguish PNaCl-produced binaries from
+     Linux binaries.
+
+     See issues https://code.google.com/p/nativeclient/issues/detail?id=2971 and
+     https://code.google.com/p/nativeclient/issues/detail?id=3313
+     for details.  */
+  if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
     return GDB_OSABI_NACL;
 
   return GDB_OSABI_UNKNOWN;
 }
 
 static void
 nacl_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
   /* NaCl uses SVR4-style shared libraries.  */
   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
@@ skipping 171 matching lines @@
 {
   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
                                   nacl_osabi_sniffer);
 
   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);
 }