Recognize GNU .note.ABI-tag values 5 (syllable) and 6 (nacl)

gdb/
	* defs.h (enum gdb_osabi): Add GDB_OSABI_SYLLABLE and GDB_OSABI_NACL.
	* osabi.c (generic_elf_osabi_sniff_abi_tag_sections): Recognize
	GNU_ABI_TAG_SYLLABLE and GNU_ABI_TAG_NACL.
	* configure.tgt (*-*-nacl*): Set gdb_osabi=GDB_OSABI_NACL.

gdb/ChangeLog

@@ -1,3 +1,10 @@
+2015-05-29  Roland McGrath  <mcgrathr@google.com>
+
+	* defs.h (enum gdb_osabi): Add GDB_OSABI_SYLLABLE and GDB_OSABI_NACL.
+	* osabi.c (generic_elf_osabi_sniff_abi_tag_sections): Recognize
+	GNU_ABI_TAG_SYLLABLE and GNU_ABI_TAG_NACL.
+	* configure.tgt (*-*-nacl*): Set gdb_osabi=GDB_OSABI_NACL.
+
 2015-05-29  Roland McGrath  <mcgrathr@google.com>
 
 	PR gdb/18464

gdb/configure.tgt

@@ -702,6 +702,7 @@ case "${targ}" in
 		gdb_osabi=GDB_OSABI_FREEBSD_ELF ;;
 *-*-linux* | *-*-uclinux*)
 		gdb_osabi=GDB_OSABI_LINUX ;;
+*-*-nacl*)	gdb_osabi=GDB_OSABI_NACL ;;
 *-*-nto*)	gdb_osabi=GDB_OSABI_QNXNTO ;;
 m68*-*-openbsd* | m88*-*-openbsd* | vax-*-openbsd*) ;;
 *-*-openbsd*)	gdb_osabi=GDB_OSABI_OPENBSD_ELF ;;

gdb/defs.h

@@ -569,6 +569,8 @@ enum gdb_osabi
   GDB_OSABI_LYNXOS178,
   GDB_OSABI_NEWLIB,
   GDB_OSABI_SDE,
+  GDB_OSABI_SYLLABLE,
+  GDB_OSABI_NACL,
 
   GDB_OSABI_INVALID		/* keep this last */
 };

gdb/osabi.c

@@ -492,6 +492,14 @@ generic_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect, void *obj)
 	      *osabi = GDB_OSABI_NETBSD_ELF;
 	      break;
 
+	    case GNU_ABI_TAG_SYLLABLE:
+	      *osabi = GDB_OSABI_SYLLABLE;
+	      break;
+
+	    case GNU_ABI_TAG_NACL:
+	      *osabi = GDB_OSABI_NACL;
+	      break;
+
 	    default:
 	      warning (_("GNU ABI tag value %u unrecognized."), abi_tag);
 	      break;