* Makefile.in (host_hook_obj): New.

	(OBJS): Add $(host_hook_obj).
	(host_default.o): New rule.
	* config.gcc (host_hook_obj): New, default to host-default.o.
	(powerpc-*-darwin*): Use host-darwin.o.
	(out_host_hook_obj): New.
	* configure: Regenerate.
	* configure.in: Print information about out_host_hook_obj, substitute
	into output files.
	* host-default.c: New file.
	* hosthooks.h: New file.
	* toplev.c (general_init): Call host_hooks.extra_signals.
	* config/rs6000/host-darwin.c: New file.
	* config/rs6000/x-darwin: New file.
	* doc/hostconfig.texi: Add documentation for new host hook.
	Rearrange existing documentation.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@62470 138bc75d-0d04-0410-961f-82ee72b054a4

12 files changed, 471 insertions, 157 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b78f7027913..aabea405b33 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,22 @@
+2003-02-05  Geoffrey Keating  <geoffk@apple.com>
+
+	* Makefile.in (host_hook_obj): New.
+	(OBJS): Add $(host_hook_obj).
+	(host_default.o): New rule.
+	* config.gcc (host_hook_obj): New, default to host-default.o.
+	(powerpc-*-darwin*): Use host-darwin.o.
+	(out_host_hook_obj): New.
+	* configure: Regenerate.
+	* configure.in: Print information about out_host_hook_obj, substitute
+	into output files.
+	* host-default.c: New file.
+	* hosthooks.h: New file.
+	* toplev.c (general_init): Call host_hooks.extra_signals.
+	* config/rs6000/host-darwin.c: New file.
+	* config/rs6000/x-darwin: New file.
+	* doc/hostconfig.texi: Add documentation for new host hook.
+	Rearrange existing documentation.
+
 2003-02-05  Roger Sayle  <roger@eyesopen.com>
 
 	* dwarf2out.c (mem_loc_descriptor): Replace ASM_SIMPLIFY_DWARF_ADDR
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 2d1c6c16170..33745f9dcb2 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -315,6 +315,7 @@ target_cpu_default=@target_cpu_default@
 GCC_THREAD_FILE=@thread_file@
 OBJC_BOEHM_GC=@objc_boehm_gc@
 GTHREAD_FLAGS=@gthread_flags@
+host_hook_obj=@out_host_hook_obj@
 # Be prepared for gcc2 merges.
 gcc_version=@gcc_version@
 gcc_version_trigger=@gcc_version_trigger@
@@ -784,7 +785,8 @@ OBJS = alias.o bb-reorder.o bitmap.o builtins.o caller-save.o calls.o	   \
  sibcall.o simplify-rtx.o ssa.o ssa-ccp.o ssa-dce.o stmt.o		   \
  stor-layout.o stringpool.o timevar.o toplev.o tracer.o tree.o tree-dump.o \
  tree-inline.o unroll.o varasm.o varray.o version.o vmsdbgout.o xcoffout.o \
- alloc-pool.o et-forest.o $(GGC) $(out_object_file) $(EXTRA_OBJS)
+ alloc-pool.o et-forest.o						   \
+ $(GGC) $(out_object_file) $(EXTRA_OBJS) $(host_hook_obj)
 
 BACKEND = main.o libbackend.a
 
@@ -1428,12 +1430,15 @@ toplev.o : toplev.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(TREE_H) $(RTL_
    dwarf2out.h sdbout.h dbxout.h $(EXPR_H) hard-reg-set.h $(BASIC_BLOCK_H) \
    graph.h $(LOOP_H) except.h $(REGS_H) $(TIMEVAR_H) $(lang_options_files) \
    ssa.h $(PARAMS_H) $(TM_P_H) reload.h dwarf2asm.h $(TARGET_H) \
-   langhooks.h insn-flags.h options.h cfglayout.h real.h cfgloop.h
+   langhooks.h insn-flags.h options.h cfglayout.h real.h cfgloop.h hosthooks.h
 	$(CC) $(ALL_CFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
 	  -DTARGET_NAME=\"$(target_alias)\" \
 	  -c $(srcdir)/toplev.c $(OUTPUT_OPTION)
 main.o : main.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) toplev.h
 
+host-default.o : host-default.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
+	hosthooks.h hosthooks-def.h
+
 rtl-error.o: rtl-error.c $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) $(INSN_ATTR_H) \
    insn-config.h input.h toplev.h intl.h diagnostic.h $(CONFIG_H)
 
diff --git a/gcc/config.gcc b/gcc/config.gcc
index 5379dfa31fd..1afbefa1bd8 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -99,6 +99,8 @@
 #  host_extra_gcc_objs	List of extra host-dependent objects that should
 #			be linked into the gcc driver.
 #
+#  out_host_hook_obj	An object file that provides the host hooks.
+#
 #  c_target_objs	List of extra target-dependent objects that be
 #			linked into the C compiler only.
 #
@@ -169,6 +171,8 @@
 #			the compiler proper when this system is a host,
 #			for host_extra_objs.
 #
+#  host_hook_obj	An object file that provides the host hooks.
+#
 #  install_headers_dir	Makefile-target for how the header file directory
 #			is installed, when this system is a build system,
 #			for build_install_headers_dir.
@@ -194,6 +198,7 @@ extra_host_objs=
 extra_gcc_objs=
 c_target_objs=
 cxx_target_objs=
+host_hook_obj=host-default.o
 tm_defines=
 xm_defines=
 # Set this to force installation and use of collect2.
@@ -1980,6 +1985,9 @@ powerpc-*-darwin*)
 	extra_headers=altivec.h
 	# override ppc default
 	need_64bit_hwint=
+	# powerpc-darwin host support.
+	host_hook_obj=host-darwin.o
+	xmake_file=rs6000/x-darwin
 	;;
 powerpc*-*-freebsd*)
 	tm_file="${tm_file} dbxelf.h elfos.h ${fbsd_tm_file} rs6000/sysv4.h rs6000/freebsd.h"
@@ -2956,6 +2964,7 @@ else
 		host_extra_gcc_objs=$extra_gcc_objs
 		host_extra_objs=$extra_host_objs
 		host_exeext=$exeext
+		out_host_hook_obj=$host_hook_obj
 		pass2done=yes
 	fi
 fi
diff --git a/gcc/config/rs6000/host-darwin.c b/gcc/config/rs6000/host-darwin.c
new file mode 100644
index 00000000000..874d691cf3c
--- /dev/null
+++ b/gcc/config/rs6000/host-darwin.c
@@ -0,0 +1,137 @@
+/* Darwin/powerpc host-specific hook definitions.
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC 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 2, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA.  */
+
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include <signal.h>
+#include <sys/ucontext.h>
+#include "hosthooks.h"
+#include "hosthooks-def.h"
+#include "toplev.h"
+
+static void segv_crash_handler PARAMS ((int));
+static void segv_handler PARAMS ((int, siginfo_t *, void *));
+static void darwin_rs6000_extra_signals PARAMS ((void));
+
+/* No prototype for this, filed as Radar 3150910.  */
+extern int sigaltstack(const stack_t *, stack_t *);
+
+#undef HOST_HOOKS_EXTRA_SIGNALS
+#define HOST_HOOKS_EXTRA_SIGNALS darwin_rs6000_extra_signals
+
+/* On Darwin/powerpc, a stack fault can be detected as a SIGSEGV that
+   faulted on an instruction that's either
+   or
+   stwux %r1,xxx,%r1
+*/
+
+static void
+segv_crash_handler (sig)
+     int sig ATTRIBUTE_UNUSED;
+{
+  internal_error ("Segmentation Fault (code)");
+}
+
+static void
+segv_handler (sig, sip, scp)
+     int sig ATTRIBUTE_UNUSED;
+     siginfo_t *sip ATTRIBUTE_UNUSED;
+     void *scp;
+{
+  ucontext_t *uc = (ucontext_t *)scp;
+  unsigned faulting_insn;
+
+  /* The fault might have happened when trying to run some instruction, in
+     which case the next line will segfault _again_.  Handle this case.  */
+  signal (SIGSEGV, segv_crash_handler);
+
+  faulting_insn = *(unsigned *)uc->uc_mcontext->ss.srr0;
+
+  /* Note that this only has to work for GCC, so we don't have to deal
+     with all the possible cases (GCC has no AltiVec code, for
+     instance).  It's complicated because Darwin allows stores to
+     below the stack pointer, and the prologue code takes advantage of
+     this.  */
+
+  if ((faulting_insn & 0xFFFF8000) == 0x94218000  /* stwu %r1, -xxx(%r1) */
+      || (faulting_insn & 0xFFFF03FF) == 0x7C21016E /* stwux %r1, xxx, %r1 */
+      || (faulting_insn & 0xFC1F8000) == 0x90018000 /* stw xxx, -yyy(%r1) */
+      || (faulting_insn & 0xFC1F8000) == 0xD8018000 /* stfd xxx, -yyy(%r1) */
+      || (faulting_insn & 0xFC1F8000) == 0xBC018000 /* stmw xxx, -yyy(%r1) */)
+    {
+      char *shell_name;
+      
+      fnotice (stderr, "Out of stack space.\n");
+      shell_name = getenv ("SHELL");
+      if (shell_name != NULL)
+	shell_name = strrchr (shell_name, '/');
+      if (shell_name != NULL)
+	{
+	  static const char * shell_commands[][2] = {
+	    { "sh", "ulimit -S -s unlimited" },
+	    { "bash", "ulimit -S -s unlimited" },
+	    { "tcsh", "limit stacksize unlimited" },
+	    { "csh", "limit stacksize unlimited" },
+	    /* zsh doesn't have "unlimited", this will work under the
+	       default configuration.  */
+	    { "zsh", "limit stacksize 32m" }
+	  };
+	  size_t i;
+	  
+	  for (i = 0; i < ARRAY_SIZE (shell_commands); i++)
+	    if (strcmp (shell_commands[i][0], shell_name + 1) == 0)
+	      {
+		fnotice (stderr, 
+			 "Try running `%s' in the shell to raise its limit.\n",
+			 shell_commands[i][1]);
+	      }
+	}
+      
+      exit (FATAL_EXIT_CODE);
+    }
+
+  fprintf (stderr, "[address=%08lx pc=%08x]\n", 
+	   uc->uc_mcontext->es.dar, uc->uc_mcontext->ss.srr0);
+  internal_error ("Segmentation Fault");
+  exit (FATAL_EXIT_CODE);
+}
+
+static void
+darwin_rs6000_extra_signals ()
+{
+  struct sigaction sact;
+  stack_t sigstk;
+
+  sigstk.ss_sp = xmalloc (SIGSTKSZ);
+  sigstk.ss_size = SIGSTKSZ;
+  sigstk.ss_flags = 0;
+  if (sigaltstack (&sigstk, NULL) < 0)
+    fatal_io_error ("While setting up signal stack");
+
+  sigemptyset(&sact.sa_mask);
+  sact.sa_flags = SA_ONSTACK | SA_SIGINFO;
+  sact.sa_sigaction = segv_handler;
+  if (sigaction (SIGSEGV, &sact, 0) < 0) 
+    fatal_io_error ("While setting up signal handler");
+}
+
+const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;
diff --git a/gcc/config/rs6000/x-darwin b/gcc/config/rs6000/x-darwin
new file mode 100644
index 00000000000..6738d45b13b
--- /dev/null
+++ b/gcc/config/rs6000/x-darwin
@@ -0,0 +1,4 @@
+host-darwin.o : $(srcdir)/config/rs6000/host-darwin.c $(CONFIG_H) $(SYSTEM_H) \
+  coretypes.h hosthooks.h hosthooks-def.h toplev.h
+	$(CC) -c $(ALL_CFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
+		$(srcdir)/config/rs6000/host-darwin.c
diff --git a/gcc/configure b/gcc/configure
index 060b1359061..18a99d372e3 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -5490,6 +5490,7 @@ else
 		echo "	$srcdir/config/$f"
 	done
 fi
+echo "Using ${out_host_hook_obj} for host machine hooks."
 
 if test "$host_xm_file" != "$build_xm_file"; then
 	count=a
@@ -5631,14 +5632,14 @@ fi
 
             
 echo $ac_n "checking for library containing strerror""... $ac_c" 1>&6
-echo "configure:5635: checking for library containing strerror" >&5
+echo "configure:5636: checking for library containing strerror" >&5
 if eval "test \"`echo '$''{'ac_cv_search_strerror'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_func_search_save_LIBS="$LIBS"
 ac_cv_search_strerror="no"
 cat > conftest.$ac_ext <<EOF
-#line 5642 "configure"
+#line 5643 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -5649,7 +5650,7 @@ int main() {
 strerror()
 ; return 0; }
 EOF
-if { (eval echo configure:5653: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5654: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_strerror="none required"
 else
@@ -5660,7 +5661,7 @@ rm -f conftest*
 test "$ac_cv_search_strerror" = "no" && for i in cposix; do
 LIBS="-l$i  $ac_func_search_save_LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 5664 "configure"
+#line 5665 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -5671,7 +5672,7 @@ int main() {
 strerror()
 ; return 0; }
 EOF
-if { (eval echo configure:5675: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5676: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_strerror="-l$i"
 break
@@ -5694,12 +5695,12 @@ fi
   
 
 echo $ac_n "checking for working const""... $ac_c" 1>&6
-echo "configure:5698: checking for working const" >&5
+echo "configure:5699: checking for working const" >&5
 if eval "test \"`echo '$''{'ac_cv_c_const'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5703 "configure"
+#line 5704 "configure"
 #include "confdefs.h"
 
 int main() {
@@ -5748,7 +5749,7 @@ ccp = (char const *const *) p;
 
 ; return 0; }
 EOF
-if { (eval echo configure:5752: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:5753: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_c_const=yes
 else
@@ -5769,12 +5770,12 @@ EOF
 fi
 
 echo $ac_n "checking for off_t""... $ac_c" 1>&6
-echo "configure:5773: checking for off_t" >&5
+echo "configure:5774: checking for off_t" >&5
 if eval "test \"`echo '$''{'ac_cv_type_off_t'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5778 "configure"
+#line 5779 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #if STDC_HEADERS
@@ -5802,12 +5803,12 @@ EOF
 fi
 
 echo $ac_n "checking for size_t""... $ac_c" 1>&6
-echo "configure:5806: checking for size_t" >&5
+echo "configure:5807: checking for size_t" >&5
 if eval "test \"`echo '$''{'ac_cv_type_size_t'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5811 "configure"
+#line 5812 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #if STDC_HEADERS
@@ -5837,19 +5838,19 @@ fi
 # The Ultrix 4.2 mips builtin alloca declared by alloca.h only works
 # for constant arguments.  Useless!
 echo $ac_n "checking for working alloca.h""... $ac_c" 1>&6
-echo "configure:5841: checking for working alloca.h" >&5
+echo "configure:5842: checking for working alloca.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_alloca_h'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5846 "configure"
+#line 5847 "configure"
 #include "confdefs.h"
 #include <alloca.h>
 int main() {
 char *p = alloca(2 * sizeof(int));
 ; return 0; }
 EOF
-if { (eval echo configure:5853: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5854: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_header_alloca_h=yes
 else
@@ -5870,12 +5871,12 @@ EOF
 fi
 
 echo $ac_n "checking for alloca""... $ac_c" 1>&6
-echo "configure:5874: checking for alloca" >&5
+echo "configure:5875: checking for alloca" >&5
 if eval "test \"`echo '$''{'ac_cv_func_alloca_works'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5879 "configure"
+#line 5880 "configure"
 #include "confdefs.h"
 
 #ifdef __GNUC__
@@ -5903,7 +5904,7 @@ int main() {
 char *p = (char *) alloca(1);
 ; return 0; }
 EOF
-if { (eval echo configure:5907: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5908: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_func_alloca_works=yes
 else
@@ -5935,12 +5936,12 @@ EOF
 
 
 echo $ac_n "checking whether alloca needs Cray hooks""... $ac_c" 1>&6
-echo "configure:5939: checking whether alloca needs Cray hooks" >&5
+echo "configure:5940: checking whether alloca needs Cray hooks" >&5
 if eval "test \"`echo '$''{'ac_cv_os_cray'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5944 "configure"
+#line 5945 "configure"
 #include "confdefs.h"
 #if defined(CRAY) && ! defined(CRAY2)
 webecray
@@ -5965,12 +5966,12 @@ echo "$ac_t""$ac_cv_os_cray" 1>&6
 if test $ac_cv_os_cray = yes; then
 for ac_func in _getb67 GETB67 getb67; do
   echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:5969: checking for $ac_func" >&5
+echo "configure:5970: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5974 "configure"
+#line 5975 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -5993,7 +5994,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:5997: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5998: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -6020,7 +6021,7 @@ done
 fi
 
 echo $ac_n "checking stack direction for C alloca""... $ac_c" 1>&6
-echo "configure:6024: checking stack direction for C alloca" >&5
+echo "configure:6025: checking stack direction for C alloca" >&5
 if eval "test \"`echo '$''{'ac_cv_c_stack_direction'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6028,7 +6029,7 @@ else
   ac_cv_c_stack_direction=0
 else
   cat > conftest.$ac_ext <<EOF
-#line 6032 "configure"
+#line 6033 "configure"
 #include "confdefs.h"
 find_stack_direction ()
 {
@@ -6047,7 +6048,7 @@ main ()
   exit (find_stack_direction() < 0);
 }
 EOF
-if { (eval echo configure:6051: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:6052: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_c_stack_direction=1
 else
@@ -6070,12 +6071,12 @@ fi
 
 
     echo $ac_n "checking whether we are using the GNU C Library 2.1 or newer""... $ac_c" 1>&6
-echo "configure:6074: checking whether we are using the GNU C Library 2.1 or newer" >&5
+echo "configure:6075: checking whether we are using the GNU C Library 2.1 or newer" >&5
 if eval "test \"`echo '$''{'ac_cv_gnu_library_2_1'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6079 "configure"
+#line 6080 "configure"
 #include "confdefs.h"
 
 #include <features.h>
@@ -6111,17 +6112,17 @@ stdlib.h string.h unistd.h sys/param.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:6115: checking for $ac_hdr" >&5
+echo "configure:6116: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6120 "configure"
+#line 6121 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:6125: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:6126: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -6152,12 +6153,12 @@ getgid getuid mempcpy munmap putenv setenv setlocale stpcpy strchr strcasecmp \
 strdup strtoul tsearch __argz_count __argz_stringify __argz_next
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:6156: checking for $ac_func" >&5
+echo "configure:6157: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6161 "configure"
+#line 6162 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -6180,7 +6181,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:6184: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6185: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -6221,7 +6222,7 @@ fi
 
 
   echo $ac_n "checking for iconv""... $ac_c" 1>&6
-echo "configure:6225: checking for iconv" >&5
+echo "configure:6226: checking for iconv" >&5
 if eval "test \"`echo '$''{'am_cv_func_iconv'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6229,7 +6230,7 @@ else
     am_cv_func_iconv="no, consider installing GNU libiconv"
     am_cv_lib_iconv=no
     cat > conftest.$ac_ext <<EOF
-#line 6233 "configure"
+#line 6234 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 #include <iconv.h>
@@ -6239,7 +6240,7 @@ iconv_t cd = iconv_open("","");
        iconv_close(cd);
 ; return 0; }
 EOF
-if { (eval echo configure:6243: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6244: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   am_cv_func_iconv=yes
 else
@@ -6251,7 +6252,7 @@ rm -f conftest*
       am_save_LIBS="$LIBS"
       LIBS="$LIBS $am_cv_libiconv_ldpath -liconv"
       cat > conftest.$ac_ext <<EOF
-#line 6255 "configure"
+#line 6256 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 #include <iconv.h>
@@ -6261,7 +6262,7 @@ iconv_t cd = iconv_open("","");
          iconv_close(cd);
 ; return 0; }
 EOF
-if { (eval echo configure:6265: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6266: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   am_cv_lib_iconv=yes
         am_cv_func_iconv=yes
@@ -6282,13 +6283,13 @@ echo "$ac_t""$am_cv_func_iconv" 1>&6
 EOF
 
     echo $ac_n "checking for iconv declaration""... $ac_c" 1>&6
-echo "configure:6286: checking for iconv declaration" >&5
+echo "configure:6287: checking for iconv declaration" >&5
     if eval "test \"`echo '$''{'am_cv_proto_iconv'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   
       cat > conftest.$ac_ext <<EOF
-#line 6292 "configure"
+#line 6293 "configure"
 #include "confdefs.h"
 
 #include <stdlib.h>
@@ -6307,7 +6308,7 @@ int main() {
 
 ; return 0; }
 EOF
-if { (eval echo configure:6311: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:6312: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   am_cv_proto_iconv_arg1=""
 else
@@ -6336,19 +6337,19 @@ EOF
 
    
   echo $ac_n "checking for nl_langinfo and CODESET""... $ac_c" 1>&6
-echo "configure:6340: checking for nl_langinfo and CODESET" >&5
+echo "configure:6341: checking for nl_langinfo and CODESET" >&5
 if eval "test \"`echo '$''{'am_cv_langinfo_codeset'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6345 "configure"
+#line 6346 "configure"
 #include "confdefs.h"
 #include <langinfo.h>
 int main() {
 char* cs = nl_langinfo(CODESET);
 ; return 0; }
 EOF
-if { (eval echo configure:6352: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6353: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   am_cv_langinfo_codeset=yes
 else
@@ -6371,19 +6372,19 @@ EOF
 
    if test $ac_cv_header_locale_h = yes; then
     echo $ac_n "checking for LC_MESSAGES""... $ac_c" 1>&6
-echo "configure:6375: checking for LC_MESSAGES" >&5
+echo "configure:6376: checking for LC_MESSAGES" >&5
 if eval "test \"`echo '$''{'am_cv_val_LC_MESSAGES'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6380 "configure"
+#line 6381 "configure"
 #include "confdefs.h"
 #include <locale.h>
 int main() {
 return LC_MESSAGES
 ; return 0; }
 EOF
-if { (eval echo configure:6387: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6388: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   am_cv_val_LC_MESSAGES=yes
 else
@@ -6404,7 +6405,7 @@ EOF
     fi
   fi
    echo $ac_n "checking whether NLS is requested""... $ac_c" 1>&6
-echo "configure:6408: checking whether NLS is requested" >&5
+echo "configure:6409: checking whether NLS is requested" >&5
         # Check whether --enable-nls or --disable-nls was given.
 if test "${enable_nls+set}" = set; then
   enableval="$enable_nls"
@@ -6427,7 +6428,7 @@ fi
 EOF
 
       echo $ac_n "checking whether included gettext is requested""... $ac_c" 1>&6
-echo "configure:6431: checking whether included gettext is requested" >&5
+echo "configure:6432: checking whether included gettext is requested" >&5
       # Check whether --with-included-gettext or --without-included-gettext was given.
 if test "${with_included_gettext+set}" = set; then
   withval="$with_included_gettext"
@@ -6447,17 +6448,17 @@ fi
 
 	ac_safe=`echo "libintl.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for libintl.h""... $ac_c" 1>&6
-echo "configure:6451: checking for libintl.h" >&5
+echo "configure:6452: checking for libintl.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6456 "configure"
+#line 6457 "configure"
 #include "confdefs.h"
 #include <libintl.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:6461: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:6462: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -6478,12 +6479,12 @@ if eval "test \"`echo '$ac_cv_header_'$ac_safe`\" = yes"; then
 EOF
 
            echo $ac_n "checking for GNU gettext in libc""... $ac_c" 1>&6
-echo "configure:6482: checking for GNU gettext in libc" >&5
+echo "configure:6483: checking for GNU gettext in libc" >&5
 if eval "test \"`echo '$''{'gt_cv_func_gnugettext1_libc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6487 "configure"
+#line 6488 "configure"
 #include "confdefs.h"
 #include <libintl.h>
 extern int _nl_msg_cat_cntr;
@@ -6492,7 +6493,7 @@ bindtextdomain ("", "");
 return (int) gettext ("") + _nl_msg_cat_cntr
 ; return 0; }
 EOF
-if { (eval echo configure:6496: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6497: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   gt_cv_func_gnugettext1_libc=yes
 else
@@ -6508,14 +6509,14 @@ echo "$ac_t""$gt_cv_func_gnugettext1_libc" 1>&6
 
 	   if test "$gt_cv_func_gnugettext1_libc" != "yes"; then
 	     echo $ac_n "checking for GNU gettext in libintl""... $ac_c" 1>&6
-echo "configure:6512: checking for GNU gettext in libintl" >&5
+echo "configure:6513: checking for GNU gettext in libintl" >&5
 if eval "test \"`echo '$''{'gt_cv_func_gnugettext1_libintl'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   gt_save_LIBS="$LIBS"
 		LIBS="$LIBS -lintl $LIBICONV"
 		cat > conftest.$ac_ext <<EOF
-#line 6519 "configure"
+#line 6520 "configure"
 #include "confdefs.h"
 #include <libintl.h>
 extern int _nl_msg_cat_cntr;
@@ -6524,7 +6525,7 @@ bindtextdomain ("", "");
 return (int) gettext ("") + _nl_msg_cat_cntr
 ; return 0; }
 EOF
-if { (eval echo configure:6528: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6529: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   gt_cv_func_gnugettext1_libintl=yes
 else
@@ -6557,12 +6558,12 @@ EOF
 	     for ac_func in dcgettext
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:6561: checking for $ac_func" >&5
+echo "configure:6562: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 6566 "configure"
+#line 6567 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -6585,7 +6586,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:6589: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:6590: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -6614,7 +6615,7 @@ done
 	     	     # Extract the first word of "msgfmt", so it can be a program name with args.
 set dummy msgfmt; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6618: checking for $ac_word" >&5
+echo "configure:6619: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_MSGFMT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6648,7 +6649,7 @@ fi
 	     # Extract the first word of "gmsgfmt", so it can be a program name with args.
 set dummy gmsgfmt; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6652: checking for $ac_word" >&5
+echo "configure:6653: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_GMSGFMT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6685,7 +6686,7 @@ fi
 	     	     # Extract the first word of "xgettext", so it can be a program name with args.
 set dummy xgettext; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6689: checking for $ac_word" >&5
+echo "configure:6690: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_XGETTEXT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6735,7 +6736,7 @@ fi
         # Extract the first word of "msgfmt", so it can be a program name with args.
 set dummy msgfmt; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6739: checking for $ac_word" >&5
+echo "configure:6740: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_MSGFMT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6769,7 +6770,7 @@ fi
         # Extract the first word of "gmsgfmt", so it can be a program name with args.
 set dummy gmsgfmt; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6773: checking for $ac_word" >&5
+echo "configure:6774: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_GMSGFMT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6805,7 +6806,7 @@ fi
         # Extract the first word of "xgettext", so it can be a program name with args.
 set dummy xgettext; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6809: checking for $ac_word" >&5
+echo "configure:6810: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_XGETTEXT'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6877,7 +6878,7 @@ do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:6881: checking for $ac_word" >&5
+echo "configure:6882: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_INTLBISON'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -6910,7 +6911,7 @@ done
       ac_verc_fail=yes
     else
             echo $ac_n "checking version of bison""... $ac_c" 1>&6
-echo "configure:6914: checking version of bison" >&5
+echo "configure:6915: checking version of bison" >&5
       ac_prog_version=`$INTLBISON --version 2>&1 | sed -n 's/^.*GNU Bison.* \([0-9]*\.[0-9.]*\).*$/\1/p'`
       case $ac_prog_version in
         '') ac_prog_version="v. ?.??, bad"; ac_verc_fail=yes;;
@@ -6955,7 +6956,7 @@ EOF
 
          if test "x$CATOBJEXT" != x; then
      echo $ac_n "checking for catalogs to be installed""... $ac_c" 1>&6
-echo "configure:6959: checking for catalogs to be installed" >&5
+echo "configure:6960: checking for catalogs to be installed" >&5
      # Look for .po and .gmo files in the source directory.
      CATALOGS=
      XLINGUAS=
@@ -7013,7 +7014,7 @@ fi
 case $host_os in
 	win32 | pe | cygwin* | mingw32* | uwin*)
 echo $ac_n "checking whether windows registry support is requested""... $ac_c" 1>&6
-echo "configure:7017: checking whether windows registry support is requested" >&5
+echo "configure:7018: checking whether windows registry support is requested" >&5
 if test "x$enable_win32_registry" != xno; then
   cat >> confdefs.h <<\EOF
 #define ENABLE_WIN32_REGISTRY 1
@@ -7022,14 +7023,14 @@ EOF
   echo "$ac_t""yes" 1>&6
   
 echo $ac_n "checking for library containing RegOpenKeyExA""... $ac_c" 1>&6
-echo "configure:7026: checking for library containing RegOpenKeyExA" >&5
+echo "configure:7027: checking for library containing RegOpenKeyExA" >&5
 if eval "test \"`echo '$''{'ac_cv_search_RegOpenKeyExA'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_func_search_save_LIBS="$LIBS"
 ac_cv_search_RegOpenKeyExA="no"
 cat > conftest.$ac_ext <<EOF
-#line 7033 "configure"
+#line 7034 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -7040,7 +7041,7 @@ int main() {
 RegOpenKeyExA()
 ; return 0; }
 EOF
-if { (eval echo configure:7044: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:7045: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_RegOpenKeyExA="none required"
 else
@@ -7051,7 +7052,7 @@ rm -f conftest*
 test "$ac_cv_search_RegOpenKeyExA" = "no" && for i in advapi32; do
 LIBS="-l$i  $ac_func_search_save_LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 7055 "configure"
+#line 7056 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -7062,7 +7063,7 @@ int main() {
 RegOpenKeyExA()
 ; return 0; }
 EOF
-if { (eval echo configure:7066: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:7067: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_RegOpenKeyExA="-l$i"
 break
@@ -7104,7 +7105,7 @@ esac
 
 if test "x$enable_win32_registry" != xno; then
   echo $ac_n "checking registry key on windows hosts""... $ac_c" 1>&6
-echo "configure:7108: checking registry key on windows hosts" >&5
+echo "configure:7109: checking registry key on windows hosts" >&5
   cat >> confdefs.h <<EOF
 #define WIN32_REGISTRY_KEY "$gcc_cv_win32_registry_key"
 EOF
@@ -7317,7 +7318,7 @@ fi
 
 # Figure out what assembler we will be using.
 echo $ac_n "checking what assembler to use""... $ac_c" 1>&6
-echo "configure:7321: checking what assembler to use" >&5
+echo "configure:7322: checking what assembler to use" >&5
 gcc_cv_as=
 gcc_cv_gas_major_version=
 gcc_cv_gas_minor_version=
@@ -7411,7 +7412,7 @@ fi
 
 # Figure out what linker we will be using.
 echo $ac_n "checking what linker to use""... $ac_c" 1>&6
-echo "configure:7415: checking what linker to use" >&5
+echo "configure:7416: checking what linker to use" >&5
 gcc_cv_ld=
 gcc_cv_gld_major_version=
 gcc_cv_gld_minor_version=
@@ -7504,7 +7505,7 @@ fi
 
 # Figure out what nm we will be using.
 echo $ac_n "checking what nm to use""... $ac_c" 1>&6
-echo "configure:7508: checking what nm to use" >&5
+echo "configure:7509: checking what nm to use" >&5
 if test -x nm$host_exeext; then
 	gcc_cv_nm=./nm$host_exeext
 elif test "x$program_prefix" != xNONE; then
@@ -7516,7 +7517,7 @@ echo "$ac_t""$gcc_cv_nm" 1>&6
 
 # Figure out what objdump we will be using.
 echo $ac_n "checking what objdump to use""... $ac_c" 1>&6
-echo "configure:7520: checking what objdump to use" >&5
+echo "configure:7521: checking what objdump to use" >&5
 if test -x objdump$host_exeext; then
 	gcc_cv_objdump=./objdump$host_exeext
 elif test "x$program_prefix" != xNONE; then
@@ -7528,7 +7529,7 @@ echo "$ac_t""$gcc_cv_objdump" 1>&6
 
 # Figure out what assembler alignment features are present.
 echo $ac_n "checking assembler alignment features""... $ac_c" 1>&6
-echo "configure:7532: checking assembler alignment features" >&5
+echo "configure:7533: checking assembler alignment features" >&5
 gcc_cv_as_alignment_features=none
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
 	# Gas version 2.6 and later support for .balign and .p2align.
@@ -7576,7 +7577,7 @@ fi
 echo "$ac_t""$gcc_cv_as_alignment_features" 1>&6
 
 echo $ac_n "checking assembler subsection support""... $ac_c" 1>&6
-echo "configure:7580: checking assembler subsection support" >&5
+echo "configure:7581: checking assembler subsection support" >&5
 gcc_cv_as_subsections=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 9 -o "$gcc_cv_gas_major_version" -gt 2 && grep 'obj_format = elf' ../gas/Makefile > /dev/null; then
@@ -7616,7 +7617,7 @@ fi
 echo "$ac_t""$gcc_cv_as_subsections" 1>&6
 
 echo $ac_n "checking assembler weak support""... $ac_c" 1>&6
-echo "configure:7620: checking assembler weak support" >&5
+echo "configure:7621: checking assembler weak support" >&5
 gcc_cv_as_weak=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 2 -o "$gcc_cv_gas_major_version" -gt 2; then
@@ -7639,7 +7640,7 @@ fi
 echo "$ac_t""$gcc_cv_as_weak" 1>&6
 
 echo $ac_n "checking assembler hidden support""... $ac_c" 1>&6
-echo "configure:7643: checking assembler hidden support" >&5
+echo "configure:7644: checking assembler hidden support" >&5
 gcc_cv_as_hidden=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2	\
@@ -7715,7 +7716,7 @@ esac
 
 
 echo $ac_n "checking assembler leb128 support""... $ac_c" 1>&6
-echo "configure:7719: checking assembler leb128 support" >&5
+echo "configure:7720: checking assembler leb128 support" >&5
 gcc_cv_as_leb128=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 11 -o "$gcc_cv_gas_major_version" -gt 2 && grep 'obj_format = elf' ../gas/Makefile > /dev/null; then
@@ -7760,7 +7761,7 @@ fi
 echo "$ac_t""$gcc_cv_as_leb128" 1>&6
 
 echo $ac_n "checking assembler eh_frame optimization""... $ac_c" 1>&6
-echo "configure:7764: checking assembler eh_frame optimization" >&5
+echo "configure:7765: checking assembler eh_frame optimization" >&5
 gcc_cv_as_eh_frame=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 12 -o "$gcc_cv_gas_major_version" -gt 2 && grep 'obj_format = elf' ../gas/Makefile > /dev/null; then
@@ -7841,7 +7842,7 @@ fi
 echo "$ac_t""$gcc_cv_as_eh_frame" 1>&6
 
 echo $ac_n "checking assembler section merging support""... $ac_c" 1>&6
-echo "configure:7845: checking assembler section merging support" >&5
+echo "configure:7846: checking assembler section merging support" >&5
 gcc_cv_as_shf_merge=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
   if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 12 -o "$gcc_cv_gas_major_version" -gt 2 && grep 'obj_format = elf' ../gas/Makefile > /dev/null; then
@@ -7864,7 +7865,7 @@ fi
 echo "$ac_t""$gcc_cv_as_shf_merge" 1>&6
 
 echo $ac_n "checking assembler thread-local storage support""... $ac_c" 1>&6
-echo "configure:7868: checking assembler thread-local storage support" >&5
+echo "configure:7869: checking assembler thread-local storage support" >&5
 gcc_cv_as_tls=no
 conftest_s=
 tls_first_major=
@@ -8007,7 +8008,7 @@ case "$target" in
   # All TARGET_ABI_OSF targets.
   alpha*-*-osf* | alpha*-*-linux* | alpha*-*-*bsd*)
     echo $ac_n "checking assembler supports explicit relocations""... $ac_c" 1>&6
-echo "configure:8011: checking assembler supports explicit relocations" >&5
+echo "configure:8012: checking assembler supports explicit relocations" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_explicit_relocs'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8057,7 +8058,7 @@ EOF
     ;;
   sparc*-*-*)
     echo $ac_n "checking assembler .register pseudo-op support""... $ac_c" 1>&6
-echo "configure:8061: checking assembler .register pseudo-op support" >&5
+echo "configure:8062: checking assembler .register pseudo-op support" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_register_pseudo_op'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8085,7 +8086,7 @@ EOF
     fi
 
     echo $ac_n "checking assembler supports -relax""... $ac_c" 1>&6
-echo "configure:8089: checking assembler supports -relax" >&5
+echo "configure:8090: checking assembler supports -relax" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_relax_opt'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8113,7 +8114,7 @@ EOF
     fi
 
     echo $ac_n "checking assembler and linker support unaligned pc related relocs""... $ac_c" 1>&6
-echo "configure:8117: checking assembler and linker support unaligned pc related relocs" >&5
+echo "configure:8118: checking assembler and linker support unaligned pc related relocs" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_sparc_ua_pcrel'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8140,7 +8141,7 @@ EOF
     fi
 
     echo $ac_n "checking assembler and linker support unaligned pc related relocs against hidden symbols""... $ac_c" 1>&6
-echo "configure:8144: checking assembler and linker support unaligned pc related relocs against hidden symbols" >&5
+echo "configure:8145: checking assembler and linker support unaligned pc related relocs against hidden symbols" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_sparc_ua_pcrel_hidden'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8180,7 +8181,7 @@ EOF
     fi
 
     echo $ac_n "checking for assembler offsetable %lo() support""... $ac_c" 1>&6
-echo "configure:8184: checking for assembler offsetable %lo() support" >&5
+echo "configure:8185: checking for assembler offsetable %lo() support" >&5
 if eval "test \"`echo '$''{'gcc_cv_as_offsetable_lo10'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -8219,7 +8220,7 @@ EOF
 
   i[34567]86-*-* | x86_64-*-*)
     echo $ac_n "checking assembler instructions""... $ac_c" 1>&6
-echo "configure:8223: checking assembler instructions" >&5
+echo "configure:8224: checking assembler instructions" >&5
     gcc_cv_as_instructions=
     if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x; then
       if test "$gcc_cv_gas_major_version" -eq 2 -a "$gcc_cv_gas_minor_version" -ge 9 -o "$gcc_cv_gas_major_version" -gt 2; then
@@ -8246,7 +8247,7 @@ EOF
     echo "$ac_t""$gcc_cv_as_instructions" 1>&6
 
     echo $ac_n "checking assembler GOTOFF in data directives""... $ac_c" 1>&6
-echo "configure:8250: checking assembler GOTOFF in data directives" >&5
+echo "configure:8251: checking assembler GOTOFF in data directives" >&5
     gcc_cv_as_gotoff_in_data=no
     if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x
     then
@@ -8276,7 +8277,7 @@ EOF
 esac
 
 echo $ac_n "checking assembler dwarf2 debug_line support""... $ac_c" 1>&6
-echo "configure:8280: checking assembler dwarf2 debug_line support" >&5
+echo "configure:8281: checking assembler dwarf2 debug_line support" >&5
 gcc_cv_as_dwarf2_debug_line=no
 # ??? Not all targets support dwarf2 debug_line, even within a version
 # of gas.  Moreover, we need to emit a valid instruction to trigger any
@@ -8333,7 +8334,7 @@ fi
 echo "$ac_t""$gcc_cv_as_dwarf2_debug_line" 1>&6
 
 echo $ac_n "checking assembler --gdwarf2 support""... $ac_c" 1>&6
-echo "configure:8337: checking assembler --gdwarf2 support" >&5
+echo "configure:8338: checking assembler --gdwarf2 support" >&5
 gcc_cv_as_gdwarf2_flag=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x;
 then
@@ -8362,7 +8363,7 @@ fi
 echo "$ac_t""$gcc_cv_as_gdwarf2_flag" 1>&6
 
 echo $ac_n "checking assembler --gstabs support""... $ac_c" 1>&6
-echo "configure:8366: checking assembler --gstabs support" >&5
+echo "configure:8367: checking assembler --gstabs support" >&5
 gcc_cv_as_gstabs_flag=no
 if test x$gcc_cv_gas_major_version != x -a x$gcc_cv_gas_minor_version != x;
 then
@@ -8390,7 +8391,7 @@ fi
 echo "$ac_t""$gcc_cv_as_gstabs_flag" 1>&6
 
 echo $ac_n "checking linker read-only and read-write section mixing""... $ac_c" 1>&6
-echo "configure:8394: checking linker read-only and read-write section mixing" >&5
+echo "configure:8395: checking linker read-only and read-write section mixing" >&5
 gcc_cv_ld_ro_rw_mix=unknown
 if test x$gcc_cv_gld_major_version != x -a x$gcc_cv_gld_minor_version != x; then
   if test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 10 -o "$gcc_cv_gld_major_version" -gt 2 && grep 'EMUL = elf' ../ld/Makefile > /dev/null; then
@@ -8428,7 +8429,7 @@ fi
 echo "$ac_t""$gcc_cv_ld_ro_rw_mix" 1>&6
 
 echo $ac_n "checking linker PT_GNU_EH_FRAME support""... $ac_c" 1>&6
-echo "configure:8432: checking linker PT_GNU_EH_FRAME support" >&5
+echo "configure:8433: checking linker PT_GNU_EH_FRAME support" >&5
 gcc_cv_ld_eh_frame_hdr=no
 if test x$gcc_cv_gld_major_version != x -a x$gcc_cv_gld_minor_version != x; then
   if test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 12 -o "$gcc_cv_gld_major_version" -gt 2 && grep 'EMUL = elf' ../ld/Makefile > /dev/null; then
@@ -8452,7 +8453,7 @@ echo "$ac_t""$gcc_cv_ld_eh_frame_hdr" 1>&6
 case "$target" in
   mips*-*-*)
     echo $ac_n "checking whether libgloss uses STARTUP directives consistently""... $ac_c" 1>&6
-echo "configure:8456: checking whether libgloss uses STARTUP directives consistently" >&5
+echo "configure:8457: checking whether libgloss uses STARTUP directives consistently" >&5
     gcc_cv_mips_libgloss_startup=no
     gcc_cv_libgloss_srcdir=`echo $srcdir | sed -e 's,/gcc$,,'`/libgloss
     if test "x$exec_prefix" = xNONE; then
@@ -8656,7 +8657,7 @@ fi
 
 
 echo $ac_n "checking whether to enable maintainer-specific portions of Makefiles""... $ac_c" 1>&6
-echo "configure:8660: checking whether to enable maintainer-specific portions of Makefiles" >&5
+echo "configure:8661: checking whether to enable maintainer-specific portions of Makefiles" >&5
     # Check whether --enable-maintainer-mode or --disable-maintainer-mode was given.
 if test "${enable_maintainer_mode+set}" = set; then
   enableval="$enable_maintainer_mode"
@@ -8969,6 +8970,7 @@ ${CONFIG_SHELL-/bin/sh} $srcdir/configure.frag $srcdir "$subdirs" "$dep_host_xma
 
 
 
+
 # Echo that links are built
 if test x$host = x$target
 then
@@ -9277,6 +9279,7 @@ s%@host_extra_gcc_objs@%$host_extra_gcc_objs%g
 s%@host_xm_file_list@%$host_xm_file_list%g
 s%@host_xm_file@%$host_xm_file%g
 s%@host_xm_defines@%$host_xm_defines%g
+s%@out_host_hook_obj@%$out_host_hook_obj%g
 s%@install@%$install%g
 s%@lang_options_files@%$lang_options_files%g
 s%@lang_specs_files@%$lang_specs_files%g
diff --git a/gcc/configure.in b/gcc/configure.in
index 4ec16ea3dcd..7376eee3448 100644
--- a/gcc/configure.in
+++ b/gcc/configure.in
@@ -956,6 +956,7 @@ else
 		echo "	$srcdir/config/$f"
 	done
 fi
+echo "Using ${out_host_hook_obj} for host machine hooks."
 
 if test "$host_xm_file" != "$build_xm_file"; then
 	count=a
@@ -2858,6 +2859,7 @@ AC_SUBST(host_extra_gcc_objs)
 AC_SUBST(host_xm_file_list)
 AC_SUBST(host_xm_file)
 AC_SUBST(host_xm_defines)
+AC_SUBST(out_host_hook_obj)
 AC_SUBST(install)
 AC_SUBST(lang_options_files)
 AC_SUBST(lang_specs_files)
diff --git a/gcc/doc/hostconfig.texi b/gcc/doc/hostconfig.texi
index 33c0a3bb28b..c13d364924d 100644
--- a/gcc/doc/hostconfig.texi
+++ b/gcc/doc/hostconfig.texi
@@ -1,51 +1,60 @@
-@c Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-@c 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+@c Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+@c 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
 @c This is part of the GCC manual.
-@c For copying conditions, see the file gcc.texi.
+@c For copying conditions, see the file gccint.texi.
 
 @node Host Config
-@chapter Host Configuration Headers
+@chapter Host Configuration
+@cindex host configuration
+
+Most details about the machine and system on which the compiler is
+actually running are detected by the @command{configure} script.  Some
+things are impossible for @command{configure} to detect; these are
+described in two ways, either by macros defined in a file named
+@file{xm-@var{machine}.h} or by hook functions in the file specified
+by the @var{out_host_hook_obj} variable in @file{config.gcc}.  (The
+intention is that very few hosts will need a header file but nearly
+every fully supported host will need to override some hooks.)
+
+If you need to define only a few macros, and they have simple
+definitions, consider using the @code{xm_defines} variable in your
+@file{config.gcc} entry instead of creating a host configuration
+header.  @xref{System Config}.
+
+@menu
+* Host Common::		Things every host probably needs implemented.
+* Filesystem::          Your host can't have the letter `a' in filenames?
+* Host Misc::         	Rare configuration options for hosts.
+@end menu
+
+@node Host Common
+@section Host Common
+@cindex host hooks
+@cindex host functions
+
+Some things are just not portable, even between similar operating systems,
+and are too difficult for autoconf to detect.  They get implemented using
+hook functions in the file specified by the @var{host_hook_obj}
+variable in @file{config.gcc}.
+
+@deftypefn {Host Hook} void HOST_HOOKS_EXTRA_SIGNALS (void)
+This host hook is used to set up handling for extra signals.  The most
+common thing to do in this hook is to detect stack overflow.
+@end deftypefn
+
+@node Filesystem
+@section Host Filesystem
 @cindex configuration file
 @cindex @file{xm-@var{machine}.h}
 
-Host configuration headers contain macro definitions that describe the
-machine and system on which the compiler is running.  They are usually
-unnecessary.  Most of the things GCC needs to know about the host
-system can be deduced by the @command{configure} script.
-
-If your host does need a special configuration header, it should be
-named @file{xm-@var{machine}.h}, where @var{machine} is a short mnemonic
-for the machine.  Here are some macros which this header can define.
+GCC supports some filesystems that are very different to standard Unix
+filesystems.  These macros, defined in @file{xm-@var{machine}.h},
+let you choose.
 
 @ftable @code
 @item VMS
 Define this macro if the host system is VMS@.
 
-@item FATAL_EXIT_CODE
-A C expression for the status code to be returned when the compiler
-exits after serious errors.  The default is the system-provided macro
-@samp{EXIT_FAILURE}, or @samp{1} if the system doesn't define that
-macro.  Define this macro only if these defaults are incorrect.
-
-@item SUCCESS_EXIT_CODE
-A C expression for the status code to be returned when the compiler
-exits without serious errors.  (Warnings are not serious errors.)  The
-default is the system-provided macro @samp{EXIT_SUCCESS}, or @samp{0} if
-the system doesn't define that macro.  Define this macro only if these
-defaults are incorrect.
-
-@item USE_C_ALLOCA
-Define this macro if GCC should use the C implementation of @code{alloca}
-provided by @file{libiberty.a}.  This only affects how some parts of the
-compiler itself allocate memory.  It does not change code generation.
-
-When GCC is built with a compiler other than itself, the C @code{alloca}
-is always used.  This is because most other implementations have serious
-bugs.  You should define this macro only on a system where no
-stack-based @code{alloca} can possibly work.  For instance, if a system
-has a small limit on the size of the stack, GCC's builtin @code{alloca}
-will not work reliably.
-
 @item HAVE_DOS_BASED_FILE_SYSTEM
 Define this macro if the host file system obeys the semantics defined by
 MS-DOS instead of Unix.  DOS file systems are case insensitive, file
@@ -86,14 +95,6 @@ you do not define this macro, GCC will use @samp{/dev/null} as the bit
 bucket.  If the host does not support a bit bucket, define this macro to
 an invalid filename.
 
-@item COLLECT2_HOST_INITIALIZATION
-If defined, a C statement (sans semicolon) that performs host-dependent
-initialization when @code{collect2} is being initialized.
-
-@item GCC_DRIVER_HOST_INITIALIZATION
-If defined, a C statement (sans semicolon) that performs host-dependent
-initialization when a compilation driver is being initialized.
-
 @item UPDATE_PATH_HOST_CANONICALIZE (@var{path})
 If defined, a C statement (sans semicolon) that performs host-dependent
 canonicalization when a path used in a compilation driver or
@@ -112,6 +113,46 @@ unique to each dump file kind, e.g. @samp{rtl}.
 
 If you do not define this macro, GCC will use @samp{.%02d.}.  You should
 define this macro if using the default will create an invalid file name.
+@end ftable
+
+@node Host Misc
+@section Host Misc
+@cindex configuration file
+@cindex @file{xm-@var{machine}.h}
+
+@ftable @code
+@item FATAL_EXIT_CODE
+A C expression for the status code to be returned when the compiler
+exits after serious errors.  The default is the system-provided macro
+@samp{EXIT_FAILURE}, or @samp{1} if the system doesn't define that
+macro.  Define this macro only if these defaults are incorrect.
+
+@item SUCCESS_EXIT_CODE
+A C expression for the status code to be returned when the compiler
+exits without serious errors.  (Warnings are not serious errors.)  The
+default is the system-provided macro @samp{EXIT_SUCCESS}, or @samp{0} if
+the system doesn't define that macro.  Define this macro only if these
+defaults are incorrect.
+
+@item USE_C_ALLOCA
+Define this macro if GCC should use the C implementation of @code{alloca}
+provided by @file{libiberty.a}.  This only affects how some parts of the
+compiler itself allocate memory.  It does not change code generation.
+
+When GCC is built with a compiler other than itself, the C @code{alloca}
+is always used.  This is because most other implementations have serious
+bugs.  You should define this macro only on a system where no
+stack-based @code{alloca} can possibly work.  For instance, if a system
+has a small limit on the size of the stack, GCC's builtin @code{alloca}
+will not work reliably.
+
+@item COLLECT2_HOST_INITIALIZATION
+If defined, a C statement (sans semicolon) that performs host-dependent
+initialization when @code{collect2} is being initialized.
+
+@item GCC_DRIVER_HOST_INITIALIZATION
+If defined, a C statement (sans semicolon) that performs host-dependent
+initialization when a compilation driver is being initialized.
 
 @item SMALL_ARG_MAX
 Define this macro if the host system has a small limit on the total
@@ -123,8 +164,3 @@ In addition, if @command{configure} generates an incorrect definition of
 any of the macros in @file{auto-host.h}, you can override that
 definition in a host configuration header.  If you need to do this,
 first see if it is possible to fix @command{configure}.
-
-If you need to define only a few of these macros, and they have simple
-definitions, consider using the @code{xm_defines} variable in your
-@file{config.gcc} entry instead of creating a host configuration header.
-@xref{System Config}.
diff --git a/gcc/host-default.c b/gcc/host-default.c
new file mode 100644
index 00000000000..b38d13aa0f9
--- /dev/null
+++ b/gcc/host-default.c
@@ -0,0 +1,28 @@
+/* Default host-specific hook definitions.
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC 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 2, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA.  */
+
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "hosthooks.h"
+#include "hosthooks-def.h"
+
+const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;
diff --git a/gcc/hosthooks-def.h b/gcc/hosthooks-def.h
new file mode 100644
index 00000000000..488e3ea2e97
--- /dev/null
+++ b/gcc/hosthooks-def.h
@@ -0,0 +1,33 @@
+/* Default macros to initialize the lang_hooks data structure.
+   Copyright 2003 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#ifndef GCC_HOST_HOOKS_DEF_H
+#define GCC_HOST_HOOKS_DEF_H
+
+#include "hooks.h"
+
+#define HOST_HOOKS_EXTRA_SIGNALS hook_void_void
+
+/* The structure is defined in hosthooks.h.  */
+#define HOST_HOOKS_INITIALIZER {		\
+  HOST_HOOKS_EXTRA_SIGNALS			\
+}
+
+#endif /* GCC_HOST_HOOKS_DEF_H */
diff --git a/gcc/hosthooks.h b/gcc/hosthooks.h
new file mode 100644
index 00000000000..92b9e5d6e32
--- /dev/null
+++ b/gcc/hosthooks.h
@@ -0,0 +1,34 @@
+/* The host_hooks data structure.
+   Copyright 2003 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#ifndef GCC_HOST_HOOKS_H
+#define GCC_HOST_HOOKS_H
+
+struct host_hooks 
+{
+  void (*extra_signals) PARAMS((void));
+
+  /* Whenever you add entries here, make sure you adjust hosthooks-def.h.  */
+};
+
+/* Each host provides its own.  */
+extern const struct host_hooks host_hooks;
+
+#endif /* GCC_LANG_HOOKS_H */
diff --git a/gcc/toplev.c b/gcc/toplev.c
index f783ed92f73..7b49110d925 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -74,6 +74,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "langhooks.h"
 #include "cfglayout.h"
 #include "cfgloop.h"
+#include "hosthooks.h"
 
 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
 #include "dwarf2out.h"
@@ -4759,6 +4760,9 @@ general_init (argv0)
   signal (SIGFPE, crash_signal);
 #endif
 
+  /* Other host-specific signal setup.  */
+  (*host_hooks.extra_signals)();
+
   /* Initialize the diagnostics reporting machinery, so option parsing
      can give warnings and errors.  */
   diagnostic_initialize (global_dc);