--- a/gcc/unwind-dw2.c	Sun Feb 07 18:28:00 2010 +0900
+++ b/gcc/unwind-dw2.c	Fri Feb 12 23:39:51 2010 +0900
@@ -1,6 +1,6 @@
 /* DWARF2 exception handling and frame unwind runtime interface routines.
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
-   2008, 2009, 2010  Free Software Foundation, Inc.
+   2008, 2009  Free Software Foundation, Inc.
 
    This file is part of GCC.
 
@@ -404,7 +404,7 @@
       else if (aug[0] == 'P')
 	{
 	  _Unwind_Ptr personality;
-	  
+
 	  p = read_encoded_value (context, *p, p + 1, &personality);
 	  fs->personality = (_Unwind_Personality_Fn) personality;
 	  aug += 1;
@@ -672,7 +672,7 @@
 	  /* Unary operations.  */
 	  gcc_assert (stack_elt);
 	  stack_elt -= 1;
-	  
+
 	  result = stack[stack_elt];
 
 	  switch (op)
@@ -749,7 +749,7 @@
 	    _Unwind_Word first, second;
 	    gcc_assert (stack_elt >= 2);
 	    stack_elt -= 2;
-	    
+
 	    second = stack[stack_elt];
 	    first = stack[stack_elt + 1];
 
@@ -765,7 +765,7 @@
 		result = second - first;
 		break;
 	      case DW_OP_mod:
-		result = second % first;
+		result = (_Unwind_Sword) second % (_Unwind_Sword) first;
 		break;
 	      case DW_OP_mul:
 		result = second * first;
@@ -822,7 +822,7 @@
 	case DW_OP_bra:
 	  gcc_assert (stack_elt);
 	  stack_elt -= 1;
-	  
+
 	  offset = read_2s (op_ptr);
 	  op_ptr += 2;
 	  if (stack[stack_elt] != 0)
@@ -902,7 +902,7 @@
 	case DW_CFA_set_loc:
 	  {
 	    _Unwind_Ptr pc;
-	    
+
 	    insn_ptr = read_encoded_value (context, fs->fde_encoding,
 					   insn_ptr, &pc);
 	    fs->pc = (void *) pc;
@@ -1164,7 +1164,7 @@
   if (fs->lsda_encoding != DW_EH_PE_omit)
     {
       _Unwind_Ptr lsda;
-      
+
       aug = read_encoded_value (context, fs->lsda_encoding, aug, &lsda);
       context->lsda = (void *) lsda;
     }
@@ -1248,7 +1248,7 @@
 		     _Unwind_SpTmp *tmp_sp)
 {
   int size = dwarf_reg_size_table[__builtin_dwarf_sp_column ()];
-  
+
   if (size == sizeof(_Unwind_Ptr))
     tmp_sp->ptr = (_Unwind_Ptr) cfa;
   else
@@ -1431,7 +1431,7 @@
   __builtin_init_dwarf_reg_size_table (dwarf_reg_size_table);
 }
 
-static void
+static void __attribute__((noinline))
 uw_init_context_1 (struct _Unwind_Context *context,
 		   void *outer_cfa, void *outer_ra)
 {
@@ -1473,18 +1473,31 @@
   context->ra = __builtin_extract_return_addr (outer_ra);
 }
 
+static void _Unwind_DebugHook (void *, void *) __attribute__ ((__noinline__));
+
+/* This function is called during unwinding.  It is intended as a hook
+   for a debugger to intercept exceptions.  CFA is the CFA of the
+   target frame.  HANDLER is the PC to which control will be
+   transferred.  */
+static void
+_Unwind_DebugHook (void *cfa __attribute__ ((__unused__)),
+		   void *handler __attribute__ ((__unused__)))
+{
+  asm ("");
+}
 
 /* Install TARGET into CURRENT so that we can return to it.  This is a
    macro because __builtin_eh_return must be invoked in the context of
    our caller.  */
 
-#define uw_install_context(CURRENT, TARGET)				 \
-  do									 \
-    {									 \
-      long offset = uw_install_context_1 ((CURRENT), (TARGET));		 \
-      void *handler = __builtin_frob_return_addr ((TARGET)->ra);	 \
-      __builtin_eh_return (offset, handler);				 \
-    }									 \
+#define uw_install_context(CURRENT, TARGET)				\
+  do									\
+    {									\
+      long offset = uw_install_context_1 ((CURRENT), (TARGET));		\
+      void *handler = __builtin_frob_return_addr ((TARGET)->ra);	\
+      _Unwind_DebugHook ((TARGET)->cfa, handler);			\
+      __builtin_eh_return (offset, handler);				\
+    }									\
   while (0)
 
 static long
@@ -1546,7 +1559,13 @@
 static inline _Unwind_Ptr
 uw_identify_context (struct _Unwind_Context *context)
 {
-  return _Unwind_GetCFA (context);
+  /* The CFA is not sufficient to disambiguate the context of a function
+     interrupted by a signal before establishing its frame and the context
+     of the signal itself.  */
+  if (STACK_GROWS_DOWNWARD)
+    return _Unwind_GetCFA (context) - _Unwind_IsSignalFrame (context);
+  else
+    return _Unwind_GetCFA (context) + _Unwind_IsSignalFrame (context);
 }