[multiple changes]

2011-10-13  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch12.adb (Analyze_Formal_{Floating_Type,
	Signed_Integer_Type,  Decimal_Fixed_Point_Type, Discrete_Type}):
	Use sloc of defining identifier of farmal type declaration,
	as sloc of generated internal entity, to prevent misplaced
	references in ali.

2011-10-13  Ed Schonberg  <schonberg@adacore.com>

	* sem_intr.adb (Check_Intrinsic_Operator): Check that type
	is fully defined before checking that it is a numeric type.

2011-10-13  Ed Schonberg  <schonberg@adacore.com>

	* sem_aggr.adb (Resolve_Record_Aggregate): If a component
	association for component X has a box, then X is covered in the
	aggregate even if there is not default value for X in the type
	declaration, and X has to be default-initialized.

2011-10-13  Ed Schonberg  <schonberg@adacore.com>

	* sem_attr.adb (Check_Enum_Image, Analyze_Attribute case
	'Value): Mark literals as referenced only if reference is in
	current source unit.

2011-10-13  Matthew Heaney  <heaney@adacore.com>

	* a-csquin.ads (Enque, Dequeue): Mark interface operations as entries.

2011-10-13  Olivier Hainque  <hainque@adacore.com>

	* sigtramp.h: New file.  Prototype and spec of the signal
	trampoline to be called by an established handler to provide
	dwarf call frame info before the real signal processing code.
	* sigtramp-ppcvxw.c: New file.	Implementation of the signal
	trampoline for ppc-vxworks.
	* init.c (vxworks section): Use it for ppc.

From-SVN: r179899

9 files changed, 415 insertions, 15 deletions

diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index ffddae3..7abe47a 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,42 @@
+2011-10-13  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_ch12.adb (Analyze_Formal_{Floating_Type,
+	Signed_Integer_Type,  Decimal_Fixed_Point_Type, Discrete_Type}):
+	Use sloc of defining identifier of farmal type declaration,
+	as sloc of generated internal entity, to prevent misplaced
+	references in ali.
+
+2011-10-13  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_intr.adb (Check_Intrinsic_Operator): Check that type
+	is fully defined before checking that it is a numeric type.
+
+2011-10-13  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_aggr.adb (Resolve_Record_Aggregate): If a component
+	association for component X has a box, then X is covered in the
+	aggregate even if there is not default value for X in the type
+	declaration, and X has to be default-initialized.
+
+2011-10-13  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_attr.adb (Check_Enum_Image, Analyze_Attribute case
+	'Value): Mark literals as referenced only if reference is in
+	current source unit.
+
+2011-10-13  Matthew Heaney  <heaney@adacore.com>
+
+	* a-csquin.ads (Enque, Dequeue): Mark interface operations as entries.
+
+2011-10-13  Olivier Hainque  <hainque@adacore.com>
+
+	* sigtramp.h: New file.  Prototype and spec of the signal
+	trampoline to be called by an established handler to provide
+	dwarf call frame info before the real signal processing code.
+	* sigtramp-ppcvxw.c: New file.	Implementation of the signal
+	trampoline for ppc-vxworks.
+	* init.c (vxworks section): Use it for ppc.
+
 2011-10-13  Thomas Quinot  <quinot@adacore.com>
 
 	* par-ch2.adb, par.adb, par-util.adb, par-ch3.adb
diff --git a/gcc/ada/a-csquin.ads b/gcc/ada/a-csquin.ads
index 2a4d0b3..7567444 100644
--- a/gcc/ada/a-csquin.ads
+++ b/gcc/ada/a-csquin.ads
@@ -42,12 +42,24 @@ package Ada.Containers.Synchronized_Queue_Interfaces is
    procedure Enqueue
      (Container : in out Queue;
       New_Item  : Element_Type) is abstract;
-   --  with Is_Synchronized => By_Entry;  ???
+
+   --  ???
+   --  This is the official Ada 2012 syntax:
+   --  with Synchronization => By_Entry;
+
+   --  This is the temporary work-around:
+   pragma Implemented (Enqueue, By_Entry);
 
    procedure Dequeue
      (Container : in out Queue;
       Element   : out Element_Type) is abstract;
-   --  with Is_Synchronized => By_Entry;  ???
+
+   --  ???
+   --  This is the official Ada 2012 syntax:
+   --  with Synchronization => By_Entry;
+
+   --  This is the temporary work-around:
+   pragma Implemented (Dequeue, By_Entry);
 
    function Current_Use (Container : Queue) return Count_Type is abstract;
 
diff --git a/gcc/ada/init.c b/gcc/ada/init.c
index 0cf32e8..9b24395 100644
--- a/gcc/ada/init.c
+++ b/gcc/ada/init.c
@@ -1906,7 +1906,8 @@ __gnat_clear_exception_count (void)
 /* Handle different SIGnal to exception mappings in different VxWorks
    versions.   */
 static void
-__gnat_map_signal (int sig)
+__gnat_map_signal (int sig, void *si ATTRIBUTE_UNUSED,
+		   struct sigcontext *sc ATTRIBUTE_UNUSED)
 {
   struct Exception_Data *exception;
   const char *msg;
@@ -2001,9 +2002,7 @@ __gnat_map_signal (int sig)
    propagation after the required low level adjustments.  */
 
 void
-__gnat_error_handler (int sig,
-		      void *si ATTRIBUTE_UNUSED,
-		      struct sigcontext *sc ATTRIBUTE_UNUSED)
+__gnat_error_handler (int sig, void *si, struct sigcontext *sc)
 {
   sigset_t mask;
 
@@ -2015,7 +2014,17 @@ __gnat_error_handler (int sig,
   sigdelset (&mask, sig);
   sigprocmask (SIG_SETMASK, &mask, NULL);
 
-  __gnat_map_signal (sig);
+#if defined (__PPC__)
+  /* We process signals through a Call Frame Info trampoline, voiding
+     the need for myriads of fallback_frame_state variants.  */
+
+  #include "sigtramp.h"
+
+  __gnat_sigtramp (sig, si, sc, &__gnat_map_signal);
+
+#else
+  __gnat_map_signal (sig, si, sc);
+#endif
 }
 
 void
diff --git a/gcc/ada/sem_aggr.adb b/gcc/ada/sem_aggr.adb
index f4d2ad8..82c7547 100644
--- a/gcc/ada/sem_aggr.adb
+++ b/gcc/ada/sem_aggr.adb
@@ -3121,6 +3121,13 @@ package body Sem_Aggr is
 
                         Expr := New_Copy_Tree (Expression (Parent (Compon)));
 
+                        --  Component may have no default, in which case the
+                        --  expression is empty and the component is default-
+                        --  initialized, but an association for the component
+                        --  exists, and it is not covered by an others clause.
+
+                        return Expr;
+
                      else
                         if Present (Next (Selector_Name)) then
                            Expr := New_Copy_Tree (Expression (Assoc));
diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
index caacc45..7b15644 100644
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -264,6 +264,10 @@ package body Sem_Attr is
       --  If the prefix type is an enumeration type, set all its literals
       --  as referenced, since the image function could possibly end up
       --  referencing any of the literals indirectly. Same for Enum_Val.
+      --  Set the flag only if the reference is in the main code unit. Same
+      --  restriction when resolving 'Value; otherwise an improperly set
+      --  reference when analyzing an inlined body will lose a proper warning
+      --  on a useless with_clause.
 
       procedure Check_Fixed_Point_Type;
       --  Verify that prefix of attribute N is a fixed type
@@ -1226,7 +1230,9 @@ package body Sem_Attr is
       procedure Check_Enum_Image is
          Lit : Entity_Id;
       begin
-         if Is_Enumeration_Type (P_Base_Type) then
+         if Is_Enumeration_Type (P_Base_Type)
+           and then In_Extended_Main_Code_Unit (N)
+         then
             Lit := First_Literal (P_Base_Type);
             while Present (Lit) loop
                Set_Referenced (Lit);
@@ -5031,7 +5037,9 @@ package body Sem_Attr is
 
          --  Case of enumeration type
 
-         if Is_Enumeration_Type (P_Type) then
+         if Is_Enumeration_Type (P_Type)
+           and then In_Extended_Main_Code_Unit (N)
+         then
             Check_Restriction (No_Enumeration_Maps, N);
 
             --  Mark all enumeration literals as referenced, since the use of
diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
index 6dd6e7b..9da8614 100644
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -1565,6 +1565,9 @@ package body Sem_Ch12 is
    --  static. For all scalar types we introduce an anonymous base type, with
    --  the same attributes. We choose the corresponding integer type to be
    --  Standard_Integer.
+   --  Here and in other similar routines, the Sloc of the generated internal
+   --  type must be the same as the sloc of the defining identifier of the
+   --  formal type declaration, to provide proper source navigation.
 
    procedure Analyze_Formal_Decimal_Fixed_Point_Type
      (T   : Entity_Id;
@@ -1574,7 +1577,8 @@ package body Sem_Ch12 is
       Base      : constant Entity_Id :=
                     New_Internal_Entity
                       (E_Decimal_Fixed_Point_Type,
-                       Current_Scope, Sloc (Def), 'G');
+                       Current_Scope,
+                         Sloc (Defining_Identifier (Parent (Def))), 'G');
       Int_Base  : constant Entity_Id := Standard_Integer;
       Delta_Val : constant Ureal := Ureal_1;
       Digs_Val  : constant Uint  := Uint_6;
@@ -1714,7 +1718,8 @@ package body Sem_Ch12 is
 
       Base : constant Entity_Id :=
                New_Internal_Entity
-                 (E_Floating_Point_Type, Current_Scope, Sloc (Def), 'G');
+                 (E_Floating_Point_Type, Current_Scope,
+                    Sloc (Defining_Identifier (Parent (Def))), 'G');
    begin
       Enter_Name          (T);
       Set_Ekind           (T, E_Enumeration_Subtype);
@@ -1762,7 +1767,8 @@ package body Sem_Ch12 is
    procedure Analyze_Formal_Floating_Type (T : Entity_Id; Def : Node_Id) is
       Base : constant Entity_Id :=
                New_Internal_Entity
-                 (E_Floating_Point_Type, Current_Scope, Sloc (Def), 'G');
+                 (E_Floating_Point_Type, Current_Scope,
+                    Sloc (Defining_Identifier (Parent (Def))), 'G');
 
    begin
       --  The various semantic attributes are taken from the predefined type
@@ -1980,7 +1986,8 @@ package body Sem_Ch12 is
       Loc  : constant Source_Ptr := Sloc (Def);
       Base : constant Entity_Id :=
                New_Internal_Entity
-                 (E_Ordinary_Fixed_Point_Type, Current_Scope, Sloc (Def), 'G');
+                 (E_Ordinary_Fixed_Point_Type, Current_Scope,
+                    Sloc (Defining_Identifier (Parent (Def))), 'G');
    begin
       --  The semantic attributes are set for completeness only, their values
       --  will never be used, since all properties of the type are non-static.
@@ -2403,7 +2410,9 @@ package body Sem_Ch12 is
    is
       Base : constant Entity_Id :=
                New_Internal_Entity
-                 (E_Signed_Integer_Type, Current_Scope, Sloc (Def), 'G');
+          (E_Signed_Integer_Type,
+           Current_Scope,
+             Sloc (Defining_Identifier (Parent (Def))), 'G');
 
    begin
       Enter_Name (T);
diff --git a/gcc/ada/sem_intr.adb b/gcc/ada/sem_intr.adb
index 1901682..26f9ff4 100644
--- a/gcc/ada/sem_intr.adb
+++ b/gcc/ada/sem_intr.adb
@@ -317,7 +317,11 @@ package body Sem_Intr is
          return;
       end if;
 
-      if not Is_Numeric_Type (Underlying_Type (T1)) then
+      --  The type must be fully defined and numeric.
+
+      if No (Underlying_Type (T1))
+        or else not Is_Numeric_Type (Underlying_Type (T1))
+      then
          Errint ("intrinsic operator can only apply to numeric types", E, N);
       end if;
    end Check_Intrinsic_Operator;
diff --git a/gcc/ada/sigtramp-ppcvxw.c b/gcc/ada/sigtramp-ppcvxw.c
new file mode 100644
index 0000000..57a02a7
--- /dev/null
+++ b/gcc/ada/sigtramp-ppcvxw.c
@@ -0,0 +1,256 @@
+/****************************************************************************
+ *                                                                          *
+ *                         GNAT COMPILER COMPONENTS                         *
+ *                                                                          *
+ *                             S I G T R A M P                              *
+ *                                                                          *
+ *                         Asm Implementation File                          *
+ *                                                                          *
+ *            Copyright (C) 2011, Free Software Foundation, Inc.            *
+ *                                                                          *
+ * GNAT is free software;  you can  redistribute it  and/or modify it under *
+ * terms of the  GNU General Public License as published  by the Free Soft- *
+ * ware  Foundation;  either version 3,  or (at your option) any later ver- *
+ * sion.  GNAT is distributed in the hope that it will be useful, but WITH- *
+ * OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY *
+ * or FITNESS FOR A PARTICULAR PURPOSE.                                     *
+ *                                                                          *
+ * As a special exception under Section 7 of GPL version 3, you are granted *
+ * additional permissions described in the GCC Runtime Library Exception,   *
+ * version 3.1, as published by the Free Software Foundation.               *
+ *                                                                          *
+ * In particular,  you can freely  distribute your programs  built with the *
+ * GNAT Pro compiler, including any required library run-time units,  using *
+ * any licensing terms  of your choosing.  See the AdaCore Software License *
+ * for full details.                                                        *
+ *                                                                          *
+ * GNAT was originally developed  by the GNAT team at  New York University. *
+ * Extensive contributions were provided by Ada Core Technologies Inc.      *
+ *                                                                          *
+ ****************************************************************************/
+
+/**********************************************************
+ * PowerPC-VxWorks version of the __gnat_sigtramp service *
+ **********************************************************/
+
+#include "sigtramp.h"
+
+#include <vxWorks.h>
+#include <arch/../regs.h>
+#include <sigLib.h>
+
+/* ----------------------
+   -- General comments --
+   ----------------------
+
+   Stubs are generated from toplevel asms and .cfi directives, much simpler
+   to use and check for correctness than manual encodings of CFI byte
+   sequences.  The general idea is to establish CFA as sigcontext->sc_pregs
+   and state where to find the registers as offsets from there.
+
+   As of today, we support a single stub, providing CFI info for common
+   registers (GPRs, LR, ...). We might need variants with support for floating
+   point or altivec registers as well at some point.
+
+   Checking which variant should apply and getting at sc_pregs is simpler
+   to express in C (we can't use offsetof in toplevel asms and hardcoding
+   constants is not workable with the flurry of VxWorks variants), so this
+   is the choice for our toplevel interface.  */
+
+/* -----------------------------------------
+   -- Protypes for our internal asm stubs --
+   -----------------------------------------
+
+   SC_PREGS is always expected to be SIGCONTEXT->sc_pregs.  Eventhough our
+   symbols will remain local, the prototype claims "extern" and not
+   "static" to prevent compiler complaints about a symbol used but never
+   defined.  */
+
+/* sigtramp stub providing CFI info for common registers.  */
+
+extern void __gnat_sigtramp_common
+(int signo, void *siginfo, void *sigcontext,
+ sighandler_t * handler, void * sc_pregs);
+
+
+/* -------------------------------------
+   -- Common interface implementation --
+   -------------------------------------
+
+   We enforce optimization to minimize the overhead of the extra layer.  */
+
+void __gnat_sigtramp (int signo, void *si, void *sc,
+		      sighandler_t * handler)
+     __attribute__((optimize(2)));
+
+void __gnat_sigtramp (int signo, void *si, void *sc,
+		      sighandler_t * handler)
+{
+  struct sigcontext * sctx = (struct sigcontext *) sc;
+
+  __gnat_sigtramp_common (signo, si, sctx, handler, sctx->sc_pregs);
+}
+
+
+/* ---------------------------
+   -- And now the asm stubs --
+   ---------------------------
+
+   They all have a common structure with blocks of asm sequences queued one
+   after the others.  Typically:
+
+   SYMBOL_START
+
+   CFI_DIRECTIVES
+     CFI_DEF_CFA,
+     CFI_COMMON_REGISTERS,
+     ...
+
+   STUB_BODY
+     asm code to establish frame, setup the cfa reg value,
+     call the real signal handler, ...
+
+   SYMBOL_END
+*/
+
+/*--------------------------------
+  -- Misc constants and helpers --
+  -------------------------------- */
+
+/* REGNO constants, dwarf column numbers for registers of interest.  */
+
+#define REGNO_LR  65
+#define REGNO_XER 76
+#define REGNO_CR  70
+#define REGNO_GR(N) (N)
+
+#define REGNO_PC  67  /* ARG_POINTER_REGNUM  */
+
+/* asm string contruction helpers.  */
+
+#define STR(TEXT) #TEXT
+/* stringify expanded TEXT, surrounding it with double quotes.  */
+
+#define S(E) STR(E)
+/* stringify E, which will resolve as text but may contain macros
+   still to be expanded.  */
+
+/* asm (TEXT) outputs <tab>TEXT. These facilitate the output of
+   multine contents:  */
+#define TAB(S) "\t" S
+#define CR(S)  S "\n"
+#define TCR(S) TAB(CR(S))
+
+/*------------------------------
+  -- Stub construction blocks --
+  ------------------------------ */
+
+/* CFA setup block
+   ---------------
+   Only non-volatile registers are suitable for a CFA base.  We use r14
+   here and set it to the value we need in stub body that follows.  */
+
+#define CFI_DEF_CFA \
+CR(".cfi_def_cfa 14, 0")
+
+/* Register location blocks
+   ------------------------
+   Rules to find registers of interest from the CFA. This should
+   comprise all the non-volatile registers relevant to the interrupted
+   context.  */
+
+#define COMMON_CFI(REG) \
+  ".cfi_offset " S(REGNO_##REG) "," S(REG_SET_##REG)
+
+#define CFI_COMMON_REGS \
+CR("# CFI for common registers\n") \
+TCR(COMMON_CFI(GR(1)))  \
+TCR(COMMON_CFI(GR(14))) \
+TCR(COMMON_CFI(GR(15))) \
+TCR(COMMON_CFI(GR(16))) \
+TCR(COMMON_CFI(GR(17))) \
+TCR(COMMON_CFI(GR(18))) \
+TCR(COMMON_CFI(GR(19))) \
+TCR(COMMON_CFI(GR(20))) \
+TCR(COMMON_CFI(GR(21))) \
+TCR(COMMON_CFI(GR(22))) \
+TCR(COMMON_CFI(GR(23))) \
+TCR(COMMON_CFI(GR(24))) \
+TCR(COMMON_CFI(GR(25))) \
+TCR(COMMON_CFI(GR(26))) \
+TCR(COMMON_CFI(GR(27))) \
+TCR(COMMON_CFI(GR(28))) \
+TCR(COMMON_CFI(GR(29))) \
+TCR(COMMON_CFI(GR(30))) \
+TCR(COMMON_CFI(GR(31))) \
+TCR(COMMON_CFI(LR)) \
+TCR(COMMON_CFI(CR)) \
+TCR(COMMON_CFI(PC)) \
+TCR(".cfi_return_column " S(REGNO_PC))
+
+/* Trampoline body block
+   ---------------------  */
+
+#define SIGTRAMP_BODY \
+CR("") \
+TCR("# Allocate frame and save the non-volatile") \
+TCR("# registers we're going to modify") \
+TCR("stwu %r1,-16(%r1)")  \
+TCR("mflr %r0")	\
+TCR("stw %r0,20(%r1)")	\
+TCR("stw %r14,8(%r1)")	\
+TCR("")			\
+TCR("# Setup r14 = sc_pregs, that we'll retrieve as our CFA value") \
+TCR("mr %r14, %r7") \
+TCR("")			\
+TCR("# Call the real handler. The signo, siginfo and sigcontext") \
+TCR("# arguments are the same as those we received in r3, r4 and r5") \
+TCR("mtctr %r6") \
+TCR("bctrl")	\
+TCR("")		\
+TCR("# Restore our callee-saved items, release our frame and return") \
+TCR("lwz %r14,8(%r1)")	\
+TCR("lwz %r0,20(%r1)")	\
+TCR("mtlr %r0")		\
+TCR("")			\
+TCR("addi %r1,%r1,16")	\
+TCR("blr")
+
+/* Symbol definition block
+   -----------------------  */
+
+#define SIGTRAMP_START(SYM) \
+CR("# " S(SYM) " cfi trampoline") \
+TCR(".type " S(SYM) ", @function") \
+CR("") \
+CR(S(SYM) ":") \
+TCR(".cfi_startproc") \
+TCR(".cfi_signal_frame")
+
+/* Symbol termination block
+   ------------------------  */
+
+#define SIGTRAMP_END(SYM) \
+CR(".cfi_endproc") \
+TCR(".size " S(SYM) ", .-" S(SYM))
+
+/*----------------------------
+  -- And now, the real code --
+  ---------------------------- */
+
+/* Text section start.  The compiler isn't aware of that switch.  */
+
+asm (".text\n"
+     TCR(".align 2"));
+
+/* sigtramp stub for common registers.  */
+
+#define TRAMP_COMMON __gnat_sigtramp_common
+
+asm (SIGTRAMP_START(TRAMP_COMMON));
+asm (CFI_DEF_CFA);
+asm (CFI_COMMON_REGS);
+asm (SIGTRAMP_BODY);
+asm (SIGTRAMP_END(TRAMP_COMMON));
+
+
diff --git a/gcc/ada/sigtramp.h b/gcc/ada/sigtramp.h
new file mode 100644
index 0000000..5e3cc5b
--- /dev/null
+++ b/gcc/ada/sigtramp.h
@@ -0,0 +1,56 @@
+/****************************************************************************
+ *                                                                          *
+ *                         GNAT COMPILER COMPONENTS                         *
+ *                                                                          *
+ *                             S I G T R A M P                              *
+ *                                                                          *
+ *                              C Header File                               *
+ *                                                                          *
+ *            Copyright (C) 2011, Free Software Foundation, Inc.            *
+ *                                                                          *
+ * GNAT is free software;  you can  redistribute it  and/or modify it under *
+ * terms of the  GNU General Public License as published  by the Free Soft- *
+ * ware  Foundation;  either version 3,  or (at your option) any later ver- *
+ * sion.  GNAT is distributed in the hope that it will be useful, but WITH- *
+ * OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY *
+ * or FITNESS FOR A PARTICULAR PURPOSE.                                     *
+ *                                                                          *
+ * As a special exception under Section 7 of GPL version 3, you are granted *
+ * additional permissions described in the GCC Runtime Library Exception,   *
+ * version 3.1, as published by the Free Software Foundation.               *
+ *                                                                          *
+ * In particular,  you can freely  distribute your programs  built with the *
+ * GNAT Pro compiler, including any required library run-time units,  using *
+ * any licensing terms  of your choosing.  See the AdaCore Software License *
+ * for full details.                                                        *
+ *                                                                          *
+ * GNAT was originally developed  by the GNAT team at  New York University. *
+ * Extensive contributions were provided by Ada Core Technologies Inc.      *
+ *                                                                          *
+ ****************************************************************************/
+
+/* On targets where this is implemented, we resort to a signal handler
+   trampoline to set-up the DWARF Call Frame Information that let unwinders
+   walk through the signal frame up into the interrupted application code.
+   This file introduces the relevant declarations.  */
+
+/* This file should only be #included on targets that do implement the
+   trampoline, which needs to expose the following interface:  */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+  typedef void sighandler_t (int signo, void *siginfo, void *sigcontext);
+
+  void __gnat_sigtramp  (int signo, void *siginfo, void *sigcontext,
+			 sighandler_t * handler);
+
+  /* To be called from an established signal handler.  Setup the DWARF CFI
+     bits letting unwinders walk through the signal frame up into the
+     interrupted application code, and then call HANDLER (SIGNO, SIGINFO,
+     SIGCONTEXT).  */
+
+#ifdef __cplusplus
+}
+#endif