patch for PR 2632

[Philip Blundell]

2002-07-12  Philip Blundell  <philb@gnu.org>

	* sysdeps/generic/backtrace.c (FIRST_FRAME_POINTER): New macro.
	(__backtrace): Use it.
	* sysdeps/arm/frame.h (FIRST_FRAME_POINTER): Define.  [PR libc/2632]

Index: sysdeps/arm/frame.h
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/arm/frame.h,v
retrieving revision 1.3
diff -u -r1.3 frame.h
--- sysdeps/arm/frame.h	6 Jul 2001 04:55:48 -0000	1.3
+++ sysdeps/arm/frame.h	12 Jul 2002 22:33:32 -0000
@@ -1,5 +1,5 @@
 /* Definition of stack frame structure.  ARM/APCS version.
-   Copyright (C) 2000 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -24,3 +24,5 @@
   void *__unbounded sp;
   void *__unbounded return_address;
 };
+
+#define FIRST_FRAME_POINTER ADVANCE_STACK_FRAME (__builtin_frame_address (0))
Index: sysdeps/generic/backtrace.c
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/generic/backtrace.c,v
retrieving revision 1.7
diff -u -r1.7 backtrace.c
--- sysdeps/generic/backtrace.c	6 Jul 2001 04:55:48 -0000	1.7
+++ sysdeps/generic/backtrace.c	12 Jul 2002 22:33:32 -0000
@@ -1,5 +1,5 @@
 /* Return backtrace of current program state.  Generic version.
-   Copyright (C) 1998, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1998, 2000, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
 
@@ -58,6 +58,11 @@
 # define ADVANCE_STACK_FRAME(next) BOUNDED_1 ((struct layout *) (next))
 #endif
 
+/* By default, the frame pointer is just what we get from gcc.  */
+#ifndef FIRST_FRAME_POINTER
+# define FIRST_FRAME_POINTER  __builtin_frame_address (0)
+#endif
+
 int
 __backtrace (array, size)
      void **array;
@@ -68,7 +73,7 @@
   void *__unbounded top_stack;
   int cnt = 0;
 
-  top_frame = __builtin_frame_address (0);
+  top_frame = FIRST_FRAME_POINTER;
   top_stack = CURRENT_STACK_FRAME;
 
   /* We skip the call to this function, it makes no sense to record it.  */